Extinctions

@misc{carson1962silent7,
    author = "Carson, R",
    title = "Silent Spring",
    year = "1962",
    howpublished = "Boston, Houghton-Mifflin",
    note = "talkorigins\_source = {true}; raw\_reference = {Carson, R., 1962, Silent Spring: Boston, Houghton-Mifflin.}"
}

@misc{newell1963crises18,
    author = "Newell, N. D",
    title = "Crises in the history of life",
    year = "1963",
    howpublished = "Scientific American, v. 208, no. 2, p. 77-92",
    note = "talkorigins\_source = {true}; raw\_reference = {Newell, N. D., 1963, Crises in the history of life: Scientific American, v. 208, no. 2, p. 77-92.}"
}

@misc{newell1967revolutions19,
    author = "Newell, N. D",
    title = "Revolutions in the history of life",
    year = "1967",
    howpublished = "Geological Society of America, Special Paper, v. 89, p. 63-91",
    note = "talkorigins\_source = {true}; raw\_reference = {Newell, N. D., 1967, Revolutions in the history of life: Geological Society of America, Special Paper, v. 89, p. 63-91.}"
}

@techreport{hays1971faunal13,
    author = "Hays, J. D",
    title = "Faunal extinctions and reversals of the earth's magnetic field",
    year = "1971",
    howpublished = "Geological Society of America Bulletin, v. 82, p. 2433-2447",
    note = "talkorigins\_source = {true}; raw\_reference = {Hays, J. D., 1971, Faunal extinctions and reversals of the earth's magnetic field: Geological Society of America Bulletin, v. 82, p. 2433-2447.}"
}

@misc{purrett1971magnetic27,
    author = "Purrett, L",
    title = "Magnetic reversals and biological extinctions",
    year = "1971",
    howpublished = "Science News, v. 100, p. 300",
    note = "talkorigins\_source = {true}; raw\_reference = {Purrett, L., 1971, Magnetic reversals and biological extinctions: Science News, v. 100, p. 300.}"
}

@misc{pitrat1973vertebrates25,
    author = "Pitrat, C. W",
    title = "Vertebrates and the Permo-Triassic extinction",
    year = "1973",
    howpublished = "Palaeogeography, Palaeoclimatology, Palaeoecology, v. 14, p. 249-264",
    note = "talkorigins\_source = {true}; raw\_reference = {Pitrat, C. W., 1973, Vertebrates and the Permo-Triassic extinction: Palaeogeography, Palaeoclimatology, Palaeoecology, v. 14, p. 249-264.}"
}

@misc{ruderman1974possible30,
    author = "Ruderman, M. A",
    title = "Possible consequences of nearby supernova explosions for atmospheric ozone and terrestrial life",
    year = "1974",
    howpublished = "Science, v. 184, p. 1079-1081",
    note = "talkorigins\_source = {true}; raw\_reference = {Ruderman, M. A., 1974, Possible consequences of nearby supernova explosions for atmospheric ozone and terrestrial life: Science, v. 184, p. 1079-1081.}"
}

@article{schopf1974permotriassic32,
    author = "Schopf, T. J. M",
    title = "Permo-Triassic extinctions",
    year = "1974",
    journal = "relations to sea floor spreading: Journal of Geology, v. 82, p. 129-143",
    note = "talkorigins\_source = {true}; raw\_reference = {Schopf, T. J. M., 1974, Permo-Triassic extinctions: relations to sea floor spreading: Journal of Geology, v. 82, p. 129-143.}"
}

@article{simberloff1974permotriassic35,
    author = "Simberloff, D. S",
    title = "Permo-Triassic extinctions",
    year = "1974",
    journal = "effects of area on biotic equilibrium: Journal of Geology, v. 82, p. 267-274",
    note = "talkorigins\_source = {true}; raw\_reference = {Simberloff, D. S., 1974, Permo-Triassic extinctions: effects of area on biotic equilibrium: Journal of Geology, v. 82, p. 267-274.}"
}

@misc{eberhart1976of10,
    author = "Eberhart, J",
    title = "Of life and death and magnetism",
    year = "1976",
    howpublished = "Science News, v. 109, p. 204",
    note = "talkorigins\_source = {true}; raw\_reference = {Eberhart, J., 1976, Of life and death and magnetism: Science News, v. 109, p. 204.}"
}

@book{bakker1977tetrapod5,
    author = "Bakker, R. T",
    title = "Tetrapod mass extinctions, in Hallem, A., ed., Patterns of Evolution",
    year = "1977",
    publisher = "Amsterdam, Elsevier Scientific Publishing Company, p. 339- 468",
    note = "talkorigins\_source = {true}; raw\_reference = {Bakker, R. T., 1977, Tetrapod mass extinctions, in Hallem, A., ed., Patterns of Evolution: Amsterdam, Elsevier Scientific Publishing Company, p. 339- 468.}"
}

@misc{olsen1977triassicjurassic23,
    author = "Olsen, P. E. and Galton, P. M",
    title = "Triassic-Jurassic tetrapod extinctions",
    year = "1977",
    howpublished = "Are they real?: Science, v. 197, p. 983-986",
    note = "talkorigins\_source = {true}; raw\_reference = {Olsen, P. E., and Galton, P. M., 1977, Triassic-Jurassic tetrapod extinctions: Are they real?: Science, v. 197, p. 983-986.}"
}

@article{russell1979the31,
    author = "Russell, D. A",
    title = "The enigma of the extinction of the dinosaurs",
    year = "1979",
    journal = "Annual Review of Earth and Planetary Sciences, v. 7, p. 163-182",
    note = "talkorigins\_source = {true}; raw\_reference = {Russell, D. A., 1979, The enigma of the extinction of the dinosaurs: Annual Review of Earth and Planetary Sciences, v. 7, p. 163-182.}"
}

Platinum metals are depleted in the earth's crust relative to their cosmic abundance; concentrations of these elements in deep-sea sediments may thus indicate influxes of extraterrestrial material. Deep-sea limestones exposed in Italy, Denmark, and New Zealand show iridium increases of about 30, 160, and 20 times, respectively, above the background level at precisely the time of the Cretaceous-Tertiary extinctions, 65 million years ago. Reasons are given to indicate that this iridium is of extraterrestrial origin, but did not come from a nearby supernova. A hypothesis is suggested which accounts for the extinctions and the iridium observations. Impact of a large earth-crossing asteroid would inject about 60 times the object's mass into the atmosphere as pulverized rock; a fraction of this dust would stay in the stratosphere for several years and be distributed worldwide. The resulting darkness would suppress photosynthesis, and the expected biological consequences match quite closely the extinctions observed in the paleontological record. One prediction of this hypothesis has been verified: the chemical composition of the boundary clay, which is thought to come from the stratospheric dust, is markedly different from that of clay mixed with the Cretaceous and Tertiary limestones, which are chemically similar to each other. Four different independent estimates of the diameter of the asteroid give values that lie in the range 10 ± 4 kilometers.

@article{alvarez1980extraterrestrial,
    author = "Alvarez, Luis W. and Alvarez, Walter and Asaro, Frank and Michel, Helen V.",
    title = "Extraterrestrial Cause for the Cretaceous-Tertiary Extinction",
    year = "1980",
    journal = "Science",
    abstract = "Platinum metals are depleted in the earth's crust relative to their cosmic abundance; concentrations of these elements in deep-sea sediments may thus indicate influxes of extraterrestrial material. Deep-sea limestones exposed in Italy, Denmark, and New Zealand show iridium increases of about 30, 160, and 20 times, respectively, above the background level at precisely the time of the Cretaceous-Tertiary extinctions, 65 million years ago. Reasons are given to indicate that this iridium is of extraterrestrial origin, but did not come from a nearby supernova. A hypothesis is suggested which accounts for the extinctions and the iridium observations. Impact of a large earth-crossing asteroid would inject about 60 times the object's mass into the atmosphere as pulverized rock; a fraction of this dust would stay in the stratosphere for several years and be distributed worldwide. The resulting darkness would suppress photosynthesis, and the expected biological consequences match quite closely the extinctions observed in the paleontological record. One prediction of this hypothesis has been verified: the chemical composition of the boundary clay, which is thought to come from the stratospheric dust, is markedly different from that of clay mixed with the Cretaceous and Tertiary limestones, which are chemically similar to each other. Four different independent estimates of the diameter of the asteroid give values that lie in the range 10 ± 4 kilometers.",
    url = "https://doi.org/10.1126/science.208.4448.1095",
    doi = "10.1126/science.208.4448.1095",
    number = "4448",
    openalex = "W2110619496",
    pages = "1095-1108",
    volume = "208",
    references = "doi101007bf00212446, doi1010160016703773900665, doi1010160031018268900473, doi101038242032a0, doi101038267403a0, doi1010970001069419540800000019, doi101126science18441411079, doi10113000167606197788367ucmsag20co2, doi10113000167606197788374ucmsag20co2, doi10113000167606197788383ucmsag20co2, doi101146annurevea07050179001115, hays1971faunal"
}

@misc{alvarez1980extraterrestrial1,
    author = "Alvarez, L. W. and Alveraz, W. and Asaro, F. and Michel, H",
    title = "Extraterrestrial cause for the Creataceous-Tertiary extinction",
    year = "1980",
    howpublished = "Science, v. 208, p. 1095- 1108",
    note = "talkorigins\_source = {true}; raw\_reference = {Alvarez, L. W., Alveraz, W., Asaro, F., and Michel, H., 1980, Extraterrestrial cause for the Creataceous-Tertiary extinction: Science, v. 208, p. 1095- 1108.}"
}

@article{alveraz1980extraterrestrial4,
    author = "Alveraz, L. W. and Alveraz, W. and Asaro, F. and Michel, H. V",
    title = "Extraterrestrial cause for the Cretaceous-Tertiary extinction",
    year = "1980",
    journal = "Science, v. 208, p. 1095-1108; See also Letters and authors' reply, Science , vol. 211, pp. 648-656",
    note = "talkorigins\_source = {true}; raw\_reference = {Alveraz, L. W., Alveraz, W., Asaro, F., and Michel, H. V., 1980, Extraterrestrial cause for the Cretaceous-Tertiary extinction: Science, v. 208, p. 1095-1108; See also Letters and authors' reply, Science , vol. 211, pp. 648-656.}"
}

@misc{cumming1980extinction8,
    author = "Cumming, K. B",
    title = "Extinction",
    year = "1980",
    howpublished = "ICR Impact Series, no. 84, p. i-iv",
    note = "talkorigins\_source = {true}; raw\_reference = {Cumming, K. B., 1980, Extinction: ICR Impact Series, no. 84, p. i-iv.}"
}

@misc{emiliani1980death11,
    author = "Emiliani, C",
    title = "Death and renovation at the end of the Mesozoic",
    year = "1980",
    howpublished = "Eos, v. 61, no. 1, p. 505-506",
    note = "talkorigins\_source = {true}; raw\_reference = {Emiliani, C., 1980, Death and renovation at the end of the Mesozoic: Eos, v. 61, no. 1, p. 505-506.}"
}

@misc{plotnick1980relationship26,
    author = "Plotnick, R. E",
    title = "Relationship between biological extinctions and geomagnetic reversals",
    year = "1980",
    howpublished = "Geology, v. 8, p. 578-581",
    note = "talkorigins\_source = {true}; raw\_reference = {Plotnick, R. E., 1980, Relationship between biological extinctions and geomagnetic reversals: Geology, v. 8, p. 578-581.}"
}

Quantitative taxonomic analyses of Late Campanian to Early Danian calcareous nannofossil assemblages suggest worldwide stable ecological conditions in the photic zone during the last 15 million years of the Mesozoic Late Cretaceous bioprovincialism was strongly paleolatitudinal The sudden extinction of the Cretaceous assemblages was followed by low supply of phytoplankton carbonate and by blooms of neritic taxa in the Early Danian indicating low productivity and ecological instability The most complete Cretaceous Tertiary boundary record studied is at DSDP Site 356 South Atlantic where thicknesses of zones close to the boundary are twice those at Gubbio Italy The mode of calcareous phytoplankton evolution appears unsuitable for tests of theoretical evolutionary models

@incollection{doi102110pec81320355,
    author = "Thierstein, Hans R.",
    title = "LATE CRETACEOUS NANNOPLANKTON AND THE CHANGE AT THE CRETACEOUS-TERTIARY BOUNDARY",
    year = "1981",
    booktitle = "SEPM (Society for Sedimentary Geology) eBooks",
    abstract = "Quantitative taxonomic analyses of Late Campanian to Early Danian calcareous nannofossil assemblages suggest worldwide stable ecological conditions in the photic zone during the last 15 million years of the Mesozoic Late Cretaceous bioprovincialism was strongly paleolatitudinal The sudden extinction of the Cretaceous assemblages was followed by low supply of phytoplankton carbonate and by blooms of neritic taxa in the Early Danian indicating low productivity and ecological instability The most complete Cretaceous Tertiary boundary record studied is at DSDP Site 356 South Atlantic where thicknesses of zones close to the boundary are twice those at Gubbio Italy The mode of calcareous phytoplankton evolution appears unsuitable for tests of theoretical evolutionary models",
    url = "https://doi.org/10.2110/pec.81.32.0355",
    doi = "10.2110/pec.81.32.0355",
    openalex = "W954468669"
}

@misc{raup1981extinction28,
    author = "Raup, D. M",
    title = "Extinction",
    year = "1981",
    howpublished = "bad genes or bad luck?: Acta Geologica Hispanica, v. 16, p. 25-33",
    note = "talkorigins\_source = {true}; raw\_reference = {Raup, D. M., 1981, Extinction: bad genes or bad luck?: Acta Geologica Hispanica, v. 16, p. 25-33.}"
}

A new compilation of fossil data on invertebrate and vertebrate families indicates that four mass extinctions in the marine realm are statistically distinct from background extinction levels. These four occurred late in the Ordovician, Permian, Triassic, and Cretaceous periods. A fifth extinction event in the Devonian stands out from the background but is not statistically significant in these data. Background extinction rates appear to have declined since Cambrian time, which is consistent with the prediction that optimization of fitness should increase through evolutionary time.

@article{doi101126science21545391501,
    author = "Raup, David M. and Sepkoski, J. John",
    title = "Mass Extinctions in the Marine Fossil Record",
    year = "1982",
    journal = "Science",
    abstract = "A new compilation of fossil data on invertebrate and vertebrate families indicates that four mass extinctions in the marine realm are statistically distinct from background extinction levels. These four occurred late in the Ordovician, Permian, Triassic, and Cretaceous periods. A fifth extinction event in the Devonian stands out from the background but is not statistically significant in these data. Background extinction rates appear to have declined since Cambrian time, which is consistent with the prediction that optimization of fitness should increase through evolutionary time.",
    url = "https://doi.org/10.1126/science.215.4539.1501",
    doi = "10.1126/science.215.4539.1501",
    openalex = "W1976721572",
    references = "doi101017s009483730000511x, doi101017s0094837300006539, doi101130spe89p63, doi105281zenodo16226412, openalexw2335729143, openalexw2591197405, openalexw2596207362"
}

The biostratigraphy of Cretaceous/Tertiary boundary sections from eight localities is summarized and compared in order to define a continuous or complete section. The El Kef, Tunisia, section is apparently the thickest C/T boundary section as yet discribed and contains all the biostratigraphical criteria required to define a complete section; that is, the uppermost Cretaceous Micula prinsiiZone, the “boundary clay” within the lowermost Tertiary Globigerina fringaZine, followed by the Globigerina eugubinaand pseudobulloidesZones. Using these zonations, a correlation of the stable-isotope stratigraphy from the various sections was made. The latest Cretaceous oceans and the earliest Tertiary oceans contained significantly different isotopic signals, which were incorporated into the tests of the calcareous nannofossils. The carbon-isotope signals are apparently global, synchronous, and primarily determined by changes in oceanic fertility, whereas the oxygen-isotope signals are globally induced but modified regionally according to paleogeographic positon and paleocirculation patterns. Further, this combination of biostratigraphy and isotope stratigraphy indicates that Cretaceous nannofossils in the lowest Tertiary sediments, previously thought to be reworked, actually survived the C/T boundary events and continued to reproduce in the earliest Tertiary oceans. These relic species became extinct some tens of thousands of years after the actual C/T boundary, probably as a consequence of the environmental stress following the C/T boundary events rather than as a result of a “catastrophic” extinction coinciding with the C/T boundary.

@incollection{doi101130spe190p353,
    author = "Perch-Nielsen, K. and McKenzie, Judith and He, Qiziang",
    title = "Biostratigraphy and isotope stratigraphy and the ‘catastrophic’ extinction of calcareous nannoplankton at the Cretaceous/Tertiary boundary",
    year = "1982",
    booktitle = "Geological Society of America eBooks",
    abstract = "The biostratigraphy of Cretaceous/Tertiary boundary sections from eight localities is summarized and compared in order to define a continuous or complete section. The El Kef, Tunisia, section is apparently the thickest C/T boundary section as yet discribed and contains all the biostratigraphical criteria required to define a complete section; that is, the uppermost Cretaceous Micula prinsiiZone, the “boundary clay” within the lowermost Tertiary Globigerina fringaZine, followed by the Globigerina eugubinaand pseudobulloidesZones. Using these zonations, a correlation of the stable-isotope stratigraphy from the various sections was made. The latest Cretaceous oceans and the earliest Tertiary oceans contained significantly different isotopic signals, which were incorporated into the tests of the calcareous nannofossils. The carbon-isotope signals are apparently global, synchronous, and primarily determined by changes in oceanic fertility, whereas the oxygen-isotope signals are globally induced but modified regionally according to paleogeographic positon and paleocirculation patterns. Further, this combination of biostratigraphy and isotope stratigraphy indicates that Cretaceous nannofossils in the lowest Tertiary sediments, previously thought to be reworked, actually survived the C/T boundary events and continued to reproduce in the earliest Tertiary oceans. These relic species became extinct some tens of thousands of years after the actual C/T boundary, probably as a consequence of the environmental stress following the C/T boundary events rather than as a result of a “catastrophic” extinction coinciding with the C/T boundary.",
    url = "https://doi.org/10.1130/spe190-p353",
    doi = "10.1130/spe190-p353",
    openalex = "W2416833765"
}

@misc{raup1982mass29,
    author = "Raup, D. M. and Sepkoski, J. J. and Jr",
    title = "Mass extinctions in the marine fossil record",
    year = "1982",
    howpublished = "Science, v. 215, p. 1501-1502",
    note = "talkorigins\_source = {true}; raw\_reference = {Raup, D. M., and Sepkoski, J. J., Jr., 1982, Mass extinctions in the marine fossil record: Science, v. 215, p. 1501-1502.}"
}

@misc{sepkoski1982mass34,
    author = "Sepkoski, J. J. and Jr",
    title = "Mass Extinctions in the Phanerozoic Oceans, in Silver, L. T., and Schultz, P. H., eds., Geological Implications of Impacts of Large Asteroids and Comets on the Earth, 190 of Geological Society of America Special Paper",
    year = "1982",
    howpublished = "Boulder, Colorado, Geological Society of America, p. 283-289",
    note = "talkorigins\_source = {true}; raw\_reference = {Sepkoski, J. J., Jr., 1982, Mass Extinctions in the Phanerozoic Oceans, in Silver, L. T., and Schultz, P. H., eds., Geological Implications of Impacts of Large Asteroids and Comets on the Earth, 190 of Geological Society of America Special Paper: Boulder, Colorado, Geological Society of America, p. 283-289.}"
}

@misc{thierstein1982terminal37,
    author = "Thierstein, H. R",
    title = "Terminal Cretaceous Plankton Extinctions, in Silver, L. T., and Schultz, P. H., eds., Geological Implications of Impacts of Large Asteroids and Comets on the Earth",
    year = "1982",
    howpublished = "Boulder, Colorado, Geological Society of America, p. 385-399; Geological Society of America Special Paper No. 190",
    note = "talkorigins\_source = {true}; raw\_reference = {Thierstein, H. R., 1982, Terminal Cretaceous Plankton Extinctions, in Silver, L. T., and Schultz, P. H., eds., Geological Implications of Impacts of Large Asteroids and Comets on the Earth: Boulder, Colorado, Geological Society of America, p. 385-399; Geological Society of America Special Paper No. 190.}"
}

This summer's meeting season saw five gatherings devoted specifically to the topic of extinction: Chicago's Field Museum symposium in May (see Diamond 1983); a field conference to examine the Cretaceous-Tertiary transition in Montana; a symposium on molluscan extinction at the American Malacological Union meeting in Seattle; a special session at the annual meeting of the Society for the Study of Evolution in St. Louis; and a research conference on the campus of Northern Arizona University in Flagstaff (see also Lewin 1983a,b,c). Several recent books consider the topic (Ehrlich and Ehrlich 1981; Nitecki 1981; Silver and Schultz 1982; Martin and Klein, 1984) and plans are underway to publish the papers presented at the Field Museum, Seattle, and Flagstaff meetings. Our review of the topic is based principally on the themes explored at the St. Louis and Flagstaff meetings.

@article{doi101017s0094837300007776,
    author = "Flessa, Karl W. and Jablonski, David",
    title = "Extinction is here to stay",
    year = "1983",
    journal = "Paleobiology",
    abstract = "This summer's meeting season saw five gatherings devoted specifically to the topic of extinction: Chicago's Field Museum symposium in May (see Diamond 1983); a field conference to examine the Cretaceous-Tertiary transition in Montana; a symposium on molluscan extinction at the American Malacological Union meeting in Seattle; a special session at the annual meeting of the Society for the Study of Evolution in St. Louis; and a research conference on the campus of Northern Arizona University in Flagstaff (see also Lewin 1983a,b,c). Several recent books consider the topic (Ehrlich and Ehrlich 1981; Nitecki 1981; Silver and Schultz 1982; Martin and Klein, 1984) and plans are underway to publish the papers presented at the Field Museum, Seattle, and Flagstaff meetings. Our review of the topic is based principally on the themes explored at the St. Louis and Flagstaff meetings.",
    url = "https://doi.org/10.1017/s0094837300007776",
    doi = "10.1017/s0094837300007776",
    openalex = "W2494791799",
    references = "doi101017s0094837300016894"
}

@misc{lewin1983extinctions16,
    author = "Lewin, R",
    title = "Extinctions and the history of life",
    year = "1983",
    howpublished = "Science, v. 221, p. 935- 937",
    note = "talkorigins\_source = {true}; raw\_reference = {Lewin, R., 1983, Extinctions and the history of life: Science, v. 221, p. 935- 937.}"
}

@misc{davis1984extinction9,
    author = "Davis, M. and Hut, P. and Muller, R. A",
    title = "Extinction by periodic comet showers",
    year = "1984",
    howpublished = "Nature, v. 308, p. 715-717",
    note = "talkorigins\_source = {true}; raw\_reference = {Davis, M., Hut, P., and Muller, R. A., 1984, Extinction by periodic comet showers: Nature, v. 308, p. 715-717.}"
}

A three-phase kinetic model with time-specific perturbations is used to describe large-scale patterns in the diversification of Phanerozoic marine families. The basic model assumes that the Cambrian, Paleozoic, and Modern evolutionary faunas each diversified logistically as a consequence of early exponential growth and of later slowing of growth as the ecosystems became filled; it also assumes interaction among the evolutionary faunas such that expansion of the combined diversities of all three faunas above any single fauna's equilibrium caused that fauna's diversity to begin to decline. This basic model adequately describes the diversification of the evolutionary faunas through the Paleozoic Era as well as the asymmetrical rise and fall of background extinction rates through the entire Phanerozoic. Declines in diversity and changes in faunal dominance associated with mass extinctions can be accommodated in the model with short-term accelerations in extinction rates or declines in equilibria. Such accelerations, or perturbations, cause diversity to decline exponentially and then to rebound sigmoidally following release. The amount of decline is dependent on the magnitude and duration of the perturbation, the timing of the perturbation with respect to the diversification of the system, and the system's initial per-taxon rates of diversification and turnover. When applied to the three-phase model, such perturbations describe the changes in diversity and faunal dominance during and after major mass extinctions, the long-term rise in total diversity following the Late Permian and Norian mass extinctions, and the peculiar diversification and then decline of the remnants of the Paleozoic fauna during the Mesozoic and Cenozoic Eras. The good fit of this model to data on Phanerozoic familial diversity suggests that many of the large-scale patterns of diversification seen in the marine fossil record of animal families are simple consequences of nonlinear interrelationships among a small number of parameters that are intrinsic to the evolutionary faunas and are largely (but not completely) invariant through time.

@article{doi101017s0094837300008186,
    author = "Sepkoski, J. John",
    title = "A kinetic model of Phanerozoic taxonomic diversity. III. Post-Paleozoic families and mass extinctions",
    year = "1984",
    journal = "Paleobiology",
    abstract = "A three-phase kinetic model with time-specific perturbations is used to describe large-scale patterns in the diversification of Phanerozoic marine families. The basic model assumes that the Cambrian, Paleozoic, and Modern evolutionary faunas each diversified logistically as a consequence of early exponential growth and of later slowing of growth as the ecosystems became filled; it also assumes interaction among the evolutionary faunas such that expansion of the combined diversities of all three faunas above any single fauna's equilibrium caused that fauna's diversity to begin to decline. This basic model adequately describes the diversification of the evolutionary faunas through the Paleozoic Era as well as the asymmetrical rise and fall of background extinction rates through the entire Phanerozoic. Declines in diversity and changes in faunal dominance associated with mass extinctions can be accommodated in the model with short-term accelerations in extinction rates or declines in equilibria. Such accelerations, or perturbations, cause diversity to decline exponentially and then to rebound sigmoidally following release. The amount of decline is dependent on the magnitude and duration of the perturbation, the timing of the perturbation with respect to the diversification of the system, and the system's initial per-taxon rates of diversification and turnover. When applied to the three-phase model, such perturbations describe the changes in diversity and faunal dominance during and after major mass extinctions, the long-term rise in total diversity following the Late Permian and Norian mass extinctions, and the peculiar diversification and then decline of the remnants of the Paleozoic fauna during the Mesozoic and Cenozoic Eras. The good fit of this model to data on Phanerozoic familial diversity suggests that many of the large-scale patterns of diversification seen in the marine fossil record of animal families are simple consequences of nonlinear interrelationships among a small number of parameters that are intrinsic to the evolutionary faunas and are largely (but not completely) invariant through time.",
    url = "https://doi.org/10.1017/s0094837300008186",
    doi = "10.1017/s0094837300008186",
    openalex = "W2221600847",
    references = "doi1010079781475707403, doi1010160012825272900724, doi1010160031018281900924, doi101017s0094837300003778, doi101017s0094837300004917, doi101017s0094837300004929, doi101017s009483730000508x, doi101017s0094837300005236, doi101017s0094837300005352, doi101017s0094837300005649, doi101017s0094837300005972, doi101017s0094837300006539, doi101017s0094837300008174, doi101038260204c0, doi101038293435a0, doi101038303614a0, doi101073pnas722646, doi101073pnas813801, doi101086627905, doi101111j1469185x1983tb00380x, doi101111j150239311977tb00628x, doi101126science2064415217, doi101126science21545391501, doi101126science2164542173, doi101126science22246281123, doi101130spe89p63, doi1015159780691206912, doi102110pec77250019, doi1023071441916, doi1023072412725, jablonski1983larval, openalexw2145250129, openalexw2989049194"
}

@article{mccartney1984the17,
    author = "McCartney, K",
    title = "The Cretaceous-Tertiary extinctions",
    year = "1984",
    journal = "Journal of Geological Education, v. 32, p. 306-309",
    note = "talkorigins\_source = {true}; raw\_reference = {McCartney, K., 1984, The Cretaceous-Tertiary extinctions: Journal of Geological Education, v. 32, p. 306-309.}"
}

@incollection{newell1984mass20,
    author = "Newell, N. D",
    editor = "Berggren, W. A. and Van Couvering, J. A.",
    title = "Mass Extinction: Unique or Recurrent Causes?",
    year = "1984",
    booktitle = "Catastrophes and Earth History",
    publisher = "The New Uniformitarianism: Princeton, New Jersey, Princeton University Press, p. 115-117",
    note = "talkorigins\_source = {true}; raw\_reference = {Newell, N. D., 1984, Mass Extinction: Unique or Recurrent Causes?, in Berggren, W. A., and Van Couvering, J. A., eds., Catastrophes and Earth History: The New Uniformitarianism: Princeton, New Jersey, Princeton University Press, p. 115-117.}"
}

@misc{officer1984terminal21,
    author = "Officer, C. B. and Drake, C. L",
    title = "Terminal Cretaceous events",
    year = "1984",
    howpublished = "Science, v. 227, p. 1161-1167",
    note = "talkorigins\_source = {true}; raw\_reference = {Officer, C. B., and Drake, C. L., 1984, Terminal Cretaceous events: Science, v. 227, p. 1161-1167.}"
}

@incollection{seilacher1984late33,
    author = "Seilacher, A",
    editor = "Holland, H. D. and Trendall, A. F.",
    title = "Late Precambrian Metazoa: Preservational or Real Extinctions?",
    year = "1984",
    booktitle = "Patterns of Change in Earth Evolution",
    publisher = "Berlin, Springer-Verlag, p. 159-168",
    note = "talkorigins\_source = {true}; raw\_reference = {Seilacher, A., 1984, Late Precambrian Metazoa: Preservational or Real Extinctions?, in Holland, H. D., and Trendall, A. F., eds., Patterns of Change in Earth Evolution: Berlin, Springer-Verlag, p. 159-168.}"
}

@book{trotter1984moas38,
    author = "Trotter, M. M. and McCulloch, B",
    title = "Moas, Man and Middens, in Martin, P. S., and Klein, R. G., eds., Quaternary Extinctions",
    year = "1984",
    publisher = "Tuscon, The University of Arizona Press, p. 708-740",
    note = "talkorigins\_source = {true}; raw\_reference = {Trotter, M. M., and McCulloch, B., 1984, Moas, Man and Middens, in Martin, P. S., and Klein, R. G., eds., Quaternary Extinctions: Tuscon, The University of Arizona Press, p. 708-740.}"
}

@misc{alvarez1986toward2,
    author = "Alvarez, W",
    title = "Toward a theory of impact crisis",
    year = "1986",
    howpublished = "Eos, v. 131, p. 248-250",
    note = "talkorigins\_source = {true}; raw\_reference = {Alvarez, W., 1986, Toward a theory of impact crisis: Eos, v. 131, p. 248-250.}"
}

@misc{bakker1986the6,
    author = "Bakker, R. T",
    title = "The Dinosaur Heresies",
    year = "1986",
    howpublished = "New Theories Unlocking the Mystery of the Dinosaurs and Their Extinction: New York, William Morrow \& Company, Inc",
    note = "talkorigins\_source = {true}; raw\_reference = {Bakker, R. T., 1986, The Dinosaur Heresies: New Theories Unlocking the Mystery of the Dinosaurs and Their Extinction: New York, William Morrow \& Company, Inc.}"
}

We report the results of new stable oxygen and carbon isotope analyses on carbonate fine fraction, whole rock, and benthic foraminifers, CaCO 3 and coarse fraction percentage determinations, and trace element (Sr) analyses on carbonate constituents across the Cretaceous/Tertiary (K/T) boundary in Deep Sea Drilling Project (DSDP) sites 47.2, 356, 384, and 577 and compare them with published results from K/T boundary sections in other DSDP sites. We used the trace element data and scanning electron microscope examination to evaluate possible diagenetic alteration and relative preservation of the samples analyzed in this study. The ∂ 18 O data when interpreted as isotopic paleotemperatures indicate relative stable surface water and deepwater temperatures in the late Maestrichtian followed by somewhat fluctuating temperatures in the early Paleocene. However, there is no indication of either a significant warming or cooling at or following the K/T boundary. Several sites do exhibit somewhat heavier ∂ 18 O values by about 0.5‰ across the boundary, which might suggest a 2‐3°C cooling at most. However, we interpret these somewhat heavier ∂ 18 O values as reflecting slightly better preservation of ∂ 18 O of carbonate constitutents in relatively clay‐rich intervals (e.g., lower diagentic potential) characteristic of the K/T boundary. The ∂ 13 C values of carbonate fine fraction and planktonic foraminifers indicate a major negative excursion in surface water total dissolved carbon across the boundary. The surface water and deepwater ∂ 13 C values from benthic foraminifers combined with calculated decreases in carbonate accumulation rates at all sites in the earliest Paleocene are consistent with a major decrease in productivity across the K/T boundary. The decrease in CaCO 3 accumulation rates is due not to increased rates of dissolution but to decreased production in surface waters. The low‐productivity episode lasted at least 1 m.y. beyond the K/T boundary crisis, suggesting that hypothesized catastrophic events alone, such as impact of an apollo object, are not the only explanation for the observed long‐term decrease in productivity. There is also an indication in the ∂ 13 C curves from several sites that the surface water ∂ 13 C decrease began in the latest Maestrichtian, suggesting that the decrease in productivity may have been independent of a hypothesized impact event.

@article{doi101029pa001i001p00005,
    author = "Zachos, James C. and Arthur, Michael A.",
    title = "Paleoceanography of the Cretaceous/Tertiary Boundary Event: Inferences from stable isotopic and other data",
    year = "1986",
    journal = "Paleoceanography",
    abstract = "We report the results of new stable oxygen and carbon isotope analyses on carbonate fine fraction, whole rock, and benthic foraminifers, CaCO 3 and coarse fraction percentage determinations, and trace element (Sr) analyses on carbonate constituents across the Cretaceous/Tertiary (K/T) boundary in Deep Sea Drilling Project (DSDP) sites 47.2, 356, 384, and 577 and compare them with published results from K/T boundary sections in other DSDP sites. We used the trace element data and scanning electron microscope examination to evaluate possible diagenetic alteration and relative preservation of the samples analyzed in this study. The ∂ 18 O data when interpreted as isotopic paleotemperatures indicate relative stable surface water and deepwater temperatures in the late Maestrichtian followed by somewhat fluctuating temperatures in the early Paleocene. However, there is no indication of either a significant warming or cooling at or following the K/T boundary. Several sites do exhibit somewhat heavier ∂ 18 O values by about 0.5‰ across the boundary, which might suggest a 2‐3°C cooling at most. However, we interpret these somewhat heavier ∂ 18 O values as reflecting slightly better preservation of ∂ 18 O of carbonate constitutents in relatively clay‐rich intervals (e.g., lower diagentic potential) characteristic of the K/T boundary. The ∂ 13 C values of carbonate fine fraction and planktonic foraminifers indicate a major negative excursion in surface water total dissolved carbon across the boundary. The surface water and deepwater ∂ 13 C values from benthic foraminifers combined with calculated decreases in carbonate accumulation rates at all sites in the earliest Paleocene are consistent with a major decrease in productivity across the K/T boundary. The decrease in CaCO 3 accumulation rates is due not to increased rates of dissolution but to decreased production in surface waters. The low‐productivity episode lasted at least 1 m.y. beyond the K/T boundary crisis, suggesting that hypothesized catastrophic events alone, such as impact of an apollo object, are not the only explanation for the observed long‐term decrease in productivity. There is also an indication in the ∂ 13 C curves from several sites that the surface water ∂ 13 C decrease began in the latest Maestrichtian, suggesting that the decrease in productivity may have been independent of a hypothesized impact event.",
    url = "https://doi.org/10.1029/pa001i001p00005",
    doi = "10.1029/pa001i001p00005",
    openalex = "W2058237753",
    references = "doi102110pec74200094"
}

Comparison of evolutionary patterns among Late Cretaceous marine bivalves and gastropods during times of normal, background levels of extinction and during the end-Cretaceous mass extinction indicates that mass extinctions are neither an intensification of background patterns nor an entirely random culling of the biota. During background times, traits such as planktotrophic larval development, broad geographic range of constituent species, and high species richness enhanced survivorship of species and genera. In contrast, during the, end-Cretaceous and other mass extinctions these factors were ineffectual, but broad geographic deployment of an entire lineage, regardless of the ranges of its constituent species, enhanced survivorship. Large-scale evolutionary patterns are evidently shaped by the alternation of these two macroevolutionary regimes, with rare but important mass extinctions driving shifts in the composition of the biota that have little relation to success during the background regime. Lineages or adaptations can be lost during mass extinctions for reasons unrelated to their survival values for organisms or species during background times, and long-term success would require the chance occurrence within a single lineage of sets of traits conducive to survivorship under both regimes.

@article{doi101126science2314734129,
    author = "Jablonski, David",
    title = "Background and Mass Extinctions: The Alternation of Macroevolutionary Regimes",
    year = "1986",
    journal = "Science",
    abstract = "Comparison of evolutionary patterns among Late Cretaceous marine bivalves and gastropods during times of normal, background levels of extinction and during the end-Cretaceous mass extinction indicates that mass extinctions are neither an intensification of background patterns nor an entirely random culling of the biota. During background times, traits such as planktotrophic larval development, broad geographic range of constituent species, and high species richness enhanced survivorship of species and genera. In contrast, during the, end-Cretaceous and other mass extinctions these factors were ineffectual, but broad geographic deployment of an entire lineage, regardless of the ranges of its constituent species, enhanced survivorship. Large-scale evolutionary patterns are evidently shaped by the alternation of these two macroevolutionary regimes, with rare but important mass extinctions driving shifts in the composition of the biota that have little relation to success during the background regime. Lineages or adaptations can be lost during mass extinctions for reasons unrelated to their survival values for organisms or species during background times, and long-term success would require the chance occurrence within a single lineage of sets of traits conducive to survivorship under both regimes.",
    url = "https://doi.org/10.1126/science.231.4734.129",
    doi = "10.1126/science.231.4734.129",
    openalex = "W2019352633",
    references = "benton1983dinosaur, doi101017s0094837300003572, doi101017s009483730000508x, doi101017s0094837300005649, doi101017s0094837300008149, doi101111j1469185x1983tb00380x, doi101111j155856461978tb04642x, doi101126science2064415217, doi101126science7041256, doi101146annurevea07050179001115, doi107312simp93764, jablonski1983larval, openalexw2145250129"
}

@misc{kitchell1986biological14,
    author = "Kitchell, J. A. and Clark, D. L. and Gombos, A. M. and Jr",
    title = "Biological selectivity of extinction",
    year = "1986",
    howpublished = "A link between background and mass extinction: Palaios, v. 1, p. 504-511",
    note = "talkorigins\_source = {true}; raw\_reference = {Kitchell, J. A., Clark, D. L., and Gombos, A. M., Jr., 1986, Biological selectivity of extinction: A link between background and mass extinction: Palaios, v. 1, p. 504-511.}"
}

@misc{sloan1986gradual36,
    author = "Sloan, R. E. et al",
    title = "Gradual dinosaur extinction and simultaneous ungulate radiation in the Hell Creek Formation",
    year = "1986",
    howpublished = "Science, v. 232, p. 629-633",
    note = "talkorigins\_source = {true}; raw\_reference = {Sloan, R. E. et al., 1986, Gradual dinosaur extinction and simultaneous ungulate radiation in the Hell Creek Formation: Science, v. 232, p. 629-633.}"
}

During the Cretaceous Period, gastropod faunas show considerable differences in their evolution between the Tethyan Realm (tropical) and the Temperate Realms to the north and south. Like Holocene faunas, prosobranch gastropods constitute the dominant part of Cretaceous marine snail faunas. Entomotaeneata and opisthobranchs usually form all of the remainder. In Tethyan faunas the Archaeogastropoda form a consistent high proportion of total taxa but less than the Mesogastropoda throughout the period. In contrast, the Temperate faunas beginning in Albian times show a decline in percentages of archaeogastropod taxa and a significant increase in the Neogastropoda, until they constitute over 50 percent of the taxa in some faunas. The neogastropods never attain high diversity in the Cretaceous of the Tethyan Realm and are judged to be of Temperate Realm origin. Cretaceous Tethyan gastropod faunas are closely allied to those of the “corallien fades” of the Jurassic and begin the period evolutionarily mature and well diversified. Greatest diversity in Tethys occurs in the lagoonal shales associated with the rudist or coral framework environments of the Cretaceous carbonate platforms. Their distribution was pan-tropical, extending in instances across the vast reaches of the Pacific. Three categories of Tethyan gastropods are analyzed. The first group consists of those of Jurassic ancestry. Except for the Nerineacea, these taxa are long ranging but evolutionarily conservative, showing only moderate diversification during the Cretaceous, and becoming extinct with the close of the era. The second group originates mainly during the Barremian and Aptian, reaches a climax in diversification during middle Cretaceous time, and usually declines during the latest Cretaceous, with most not lasting through the terminal event. The third group originates late in the Cretaceous and consists of taxa that manage to either survive the Cretaceous-Tertiary crisis or give rise to forms of prominence among Tertiary warm water faunas. There is a trend among the Tethyan gastropod assemblages for increased provincialism with time. Early and middle Cretaceous taxa are especially widely distributed, but the latest Cretaceous is a time of restricted occurrence for many forms. Temperate Realm gastropod faunas are less diverse than those of Tethys during the Early Cretaceous. Their source is among long lived, extra-Tethys groups, but is increased, especially during major phases of transgression, by immigrants from Tethys. They show a steady increase in diversity, primarily among the Mesogastropoda and Neogastropoda. This trend culminates in latest Cretaceous times when the gastropod assemblages of the clastic provinces of the inner shelf contain an abundance of taxa outstripping that of any other part of the Cretaceous of either realm. Extinction at the Cretaceous-Tertiary boundary is much less pronounced in the Temperate Realm than in the Tethys. Among the Temperate Realm assemblages loss is of generic and species level taxa, unlike the extinction of the family Actaeonellidae or the superfamily Nerineacea and a host of less prominent groups in Tethys. In essence, by the late Maastrichtian, gastropod faunas of the Temperate Realm had attained a modern faunal aspect.

@article{doi101017s0022336000029486,
    author = "Sohl, Norman F.",
    title = "Cretaceous gastropods: contrasts between Tethys and the temperate provinces",
    year = "1987",
    journal = "Journal of Paleontology",
    abstract = "During the Cretaceous Period, gastropod faunas show considerable differences in their evolution between the Tethyan Realm (tropical) and the Temperate Realms to the north and south. Like Holocene faunas, prosobranch gastropods constitute the dominant part of Cretaceous marine snail faunas. Entomotaeneata and opisthobranchs usually form all of the remainder. In Tethyan faunas the Archaeogastropoda form a consistent high proportion of total taxa but less than the Mesogastropoda throughout the period. In contrast, the Temperate faunas beginning in Albian times show a decline in percentages of archaeogastropod taxa and a significant increase in the Neogastropoda, until they constitute over 50 percent of the taxa in some faunas. The neogastropods never attain high diversity in the Cretaceous of the Tethyan Realm and are judged to be of Temperate Realm origin. Cretaceous Tethyan gastropod faunas are closely allied to those of the “corallien fades” of the Jurassic and begin the period evolutionarily mature and well diversified. Greatest diversity in Tethys occurs in the lagoonal shales associated with the rudist or coral framework environments of the Cretaceous carbonate platforms. Their distribution was pan-tropical, extending in instances across the vast reaches of the Pacific. Three categories of Tethyan gastropods are analyzed. The first group consists of those of Jurassic ancestry. Except for the Nerineacea, these taxa are long ranging but evolutionarily conservative, showing only moderate diversification during the Cretaceous, and becoming extinct with the close of the era. The second group originates mainly during the Barremian and Aptian, reaches a climax in diversification during middle Cretaceous time, and usually declines during the latest Cretaceous, with most not lasting through the terminal event. The third group originates late in the Cretaceous and consists of taxa that manage to either survive the Cretaceous-Tertiary crisis or give rise to forms of prominence among Tertiary warm water faunas. There is a trend among the Tethyan gastropod assemblages for increased provincialism with time. Early and middle Cretaceous taxa are especially widely distributed, but the latest Cretaceous is a time of restricted occurrence for many forms. Temperate Realm gastropod faunas are less diverse than those of Tethys during the Early Cretaceous. Their source is among long lived, extra-Tethys groups, but is increased, especially during major phases of transgression, by immigrants from Tethys. They show a steady increase in diversity, primarily among the Mesogastropoda and Neogastropoda. This trend culminates in latest Cretaceous times when the gastropod assemblages of the clastic provinces of the inner shelf contain an abundance of taxa outstripping that of any other part of the Cretaceous of either realm. Extinction at the Cretaceous-Tertiary boundary is much less pronounced in the Temperate Realm than in the Tethys. Among the Temperate Realm assemblages loss is of generic and species level taxa, unlike the extinction of the family Actaeonellidae or the superfamily Nerineacea and a host of less prominent groups in Tethys. In essence, by the late Maastrichtian, gastropod faunas of the Temperate Realm had attained a modern faunal aspect.",
    url = "https://doi.org/10.1017/s0022336000029486",
    doi = "10.1017/s0022336000029486",
    openalex = "W1590924657",
    references = "doi101017s0094837300005352, doi101111j150239311976tb01317x, doi101127njgpa1551977137, doi101130mem64p1, doi102110pec81300399, doi102113gssgfbulli5637, doi1023071485443, doi103133pp331b, doi103133pp393b, doi105281zenodo15959493, doi105281zenodo16196838, openalexw1483032662, openalexw2301295998, sohl1960archeogastropoda, sohl1967upper"
}

@incollection{leahy1987the15,
    author = "Leahy, G. D",
    editor = "Currie, P. J. and Koster, E.",
    title = "The Gradual Extinction of Dinosaurs: Fact of Artifact?",
    year = "1987",
    booktitle = "Fourth Symposium on Mesozoic Terrestrial Ecosystems",
    publisher = "Drumheller, Canada, Tyrrell Museum, p. 138-143",
    note = "talkorigins\_source = {true}; raw\_reference = {Leahy, G. D., 1987, The Gradual Extinction of Dinosaurs: Fact of Artifact?, in Currie, P. J., and Koster, E., eds., Fourth Symposium on Mesozoic Terrestrial Ecosystems: Drumheller, Canada, Tyrrell Museum, p. 138-143.}"
}

@misc{officer1987late22,
    author = "Officer, C. B. et al",
    title = "Late Cretaceous and paroxysmal Cretaceous/Tertiary extinctions",
    year = "1987",
    howpublished = "Nature, v. 326, p. 143-149",
    note = "talkorigins\_source = {true}; raw\_reference = {Officer, C. B. et al., 1987, Late Cretaceous and paroxysmal Cretaceous/Tertiary extinctions: Nature, v. 326, p. 143-149.}"
}

Here is one biologist's interpretation of the chronology of life during the last six hundred million years of earth history: an extended essay that draws on the author's own data and a wide-ranging literature survey to discuss the nature and dynamics of evolutionary change in organisms and their biological surroundings. Geerat Vermeij demonstrates that escalation--the process by which species adapt to, or are limited by, their enemies as the latter increase in ability to acquire and retain resources--has been a dominant theme in the history of life despite frequent episodes of extinction.

@book{openalexw1528487914,
    author = "Vermeij, Geerat J.",
    title = "Evolution and Escalation: An Ecological History of Life",
    year = "1987",
    abstract = "Here is one biologist's interpretation of the chronology of life during the last six hundred million years of earth history: an extended essay that draws on the author's own data and a wide-ranging literature survey to discuss the nature and dynamics of evolutionary change in organisms and their biological surroundings. Geerat Vermeij demonstrates that escalation--the process by which species adapt to, or are limited by, their enemies as the latter increase in ability to acquire and retain resources--has been a dominant theme in the history of life despite frequent episodes of extinction.",
    openalex = "W1528487914"
}

@misc{weisburd1987volcanoes39,
    author = "Weisburd, S",
    title = "Volcanoes and extinctions",
    year = "1987",
    howpublished = "Round two: Science News, v. 131, p. 248-250",
    note = "talkorigins\_source = {true}; raw\_reference = {Weisburd, S., 1987, Volcanoes and extinctions: Round two: Science News, v. 131, p. 248-250.}"
}

@article{doi1010160377839888900059,
    author = "Keller, Gerta",
    title = "Extinction, survivorship and evolution of planktic foraminifera across the Cretaceous/Tertiary boundary at El Kef, Tunisia",
    year = "1988",
    journal = "Marine Micropaleontology",
    url = "https://doi.org/10.1016/0377-8398(88)90005-9",
    doi = "10.1016/0377-8398(88)90005-9",
    openalex = "W2100106592"
}

Predicting the extinction of single populations or species requires ecological and evolutionary information. Primary demographic factors affecting population dynamics include social structure, life history variation caused by environmental fluctuation, dispersal in spatially heterogeneous environments, and local extinction and colonization. In small populations, inbreeding can greatly reduce the average individual fitness, and loss of genetic variability from random genetic drift can diminish future adaptability to a changing environment. Theory and empirical examples suggest that demography is usually of more immediate importance than population genetics in determining the minimum viable sizes of wild populations. The practical need in biological conservation for understanding the interaction of demographic and genetic factors in extinction may provide a focus for fundamental advances at the interface of ecology and evolution.

@article{doi101126science3420403,
    author = "Lande, Russell",
    title = "Genetics and Demography in Biological Conservation",
    year = "1988",
    journal = "Science",
    abstract = "Predicting the extinction of single populations or species requires ecological and evolutionary information. Primary demographic factors affecting population dynamics include social structure, life history variation caused by environmental fluctuation, dispersal in spatially heterogeneous environments, and local extinction and colonization. In small populations, inbreeding can greatly reduce the average individual fitness, and loss of genetic variability from random genetic drift can diminish future adaptability to a changing environment. Theory and empirical examples suggest that demography is usually of more immediate importance than population genetics in determining the minimum viable sizes of wild populations. The practical need in biological conservation for understanding the interaction of demographic and genetic factors in extinction may provide a focus for fundamental advances at the interface of ecology and evolution.",
    url = "https://doi.org/10.1126/science.3420403",
    doi = "10.1126/science.3420403",
    openalex = "W2094387116",
    references = "doi101016000632078690025x, doi101016c20090029523, doi101017s0016672300016037, doi101093besa153237, doi101111j146918091949tb02451x, doi101111j155856461975tb00851x, doi101126science2214609459, doi101126science2314734129, doi101146annureves18110187001321, doi1015159781400881376, doi1023071308256, doi1023072529912, openalexw1500291103, openalexw2318111898"
}

@book{guth1988the12,
    author = "Guth, A. H",
    title = "The Birth of the Cosmos, in Osterbrock, D. E., and Raven, P. H., eds., Origins and Extinctions",
    year = "1988",
    publisher = "New Haven, Connecticut, Yale University Press, p. 1-41",
    note = "talkorigins\_source = {true}; raw\_reference = {Guth, A. H., 1988, The Birth of the Cosmos, in Osterbrock, D. E., and Raven, P. H., eds., Origins and Extinctions: New Haven, Connecticut, Yale University Press, p. 1-41.}"
}

Several abrupt changes in conodont biofacies are documented to occur synchronously at six primary control sections across the Frasnian-Famennian boundary in Euramerica. These changes occurred within a time-span of only about 100,000 years near the end of the latest Frasnian linguiformis Zone, which is formally named to replace the Uppermost gigas Zone. The conodont-biofacies changes are interpreted to reflect a eustatic rise followed by an abrupt eustatic fall immediately preceding the late Frasnian mass extinction. Two new conodont species are named and described. Ancyrognathus ubiquitus n.sp. is recorded only just below and above the level of late Frasnian extinction and hence is a global marker for that event. Palmatolepispraetriangularis n.sp. is the long-sought Frasnian ancestor of the formerly cryptogenic species, Pa. triangularis, indicator of the earliest Famennian Lower triangularis Zone. The actual extinction event occurred entirely within the Frasnian and is interpreted to have been of brief duration-from as long as 20,000 years to as short as several days. The eustatic rise-and-fall couplet associated with the late Frasnian mass extinction is similar to eustatic couplets associated with the demise of most Frasnian (F2h) reefs worldwide about 1 m.y. earlier and with a latest Famennian mass extinction about 9.5 m.y. later. All these events may be directly or indirectly attributable to extraterrestrial triggering mechanisms. An impact of a small bolide or a near miss of a larger bolide may have caused the earlier demise of Frasnian reefs. An impact of possibly the same larger bolide in the Southern Hemisphere would explain the late Frasnian mass extinction. Global regression during the Famennian probably resulted from Southern-Hemisphere glaciation triggered by the latest Frasnian impact. Glaciation probably was the indirect cause of the latest Famennian mass extinction.

@article{openalexw1536160709,
    author = "Sandberg, Charles A. and Ziegler, Willi and Dreesen, Roland and Butler, Jamie L.",
    title = "Late Frasnian Mass Extinction: Conodont Event Stratigraphy, Global Changes, and Possible Causes",
    year = "1988",
    journal = "NASA STI Repository (National Aeronautics and Space Administration)",
    abstract = "Several abrupt changes in conodont biofacies are documented to occur synchronously at six primary control sections across the Frasnian-Famennian boundary in Euramerica. These changes occurred within a time-span of only about 100,000 years near the end of the latest Frasnian linguiformis Zone, which is formally named to replace the Uppermost gigas Zone. The conodont-biofacies changes are interpreted to reflect a eustatic rise followed by an abrupt eustatic fall immediately preceding the late Frasnian mass extinction. Two new conodont species are named and described. Ancyrognathus ubiquitus n.sp. is recorded only just below and above the level of late Frasnian extinction and hence is a global marker for that event. Palmatolepispraetriangularis n.sp. is the long-sought Frasnian ancestor of the formerly cryptogenic species, Pa. triangularis, indicator of the earliest Famennian Lower triangularis Zone. The actual extinction event occurred entirely within the Frasnian and is interpreted to have been of brief duration-from as long as 20,000 years to as short as several days. The eustatic rise-and-fall couplet associated with the late Frasnian mass extinction is similar to eustatic couplets associated with the demise of most Frasnian (F2h) reefs worldwide about 1 m.y. earlier and with a latest Famennian mass extinction about 9.5 m.y. later. All these events may be directly or indirectly attributable to extraterrestrial triggering mechanisms. An impact of a small bolide or a near miss of a larger bolide may have caused the earlier demise of Frasnian reefs. An impact of possibly the same larger bolide in the Southern Hemisphere would explain the late Frasnian mass extinction. Global regression during the Famennian probably resulted from Southern-Hemisphere glaciation triggered by the latest Frasnian impact. Glaciation probably was the indirect cause of the latest Famennian mass extinction.",
    openalex = "W1536160709"
}

@book{osterbrock1988origins24,
    author = "Osterbrock, D. E. and Raven, P. H",
    title = "Origins and Extinctions",
    year = "1988",
    publisher = "New Haven, Connecticut, Yale University Press",
    note = "talkorigins\_source = {true}; raw\_reference = {Osterbrock, D. E., and Raven, P. H., 1988, Origins and Extinctions: New Haven, Connecticut, Yale University Press.}"
}

The hypothesis that extinction events have recurred periodically over the last quarter billion years is greatly strengthened by new data on the stratigraphic ranges of marine animal genera. In the interval from the Permian to Recent, these data encompass some 13,000 generic extinctions, providing a more sensitive indicator of species-level extinctions than previously used familial data. Extinction time series computed from the generic data display nine strong peaks that are nearly uniformly spaced at 26 Ma intervals over the last 270 Ma. Most of these peaks correspond to extinction events recognized in more detailed, if limited, biostratigraphic studies. These new data weaken or negate most arguments against periodicity, which have involved criticisms of the taxonomic data base, sampling intervals, chronometric time scales, and statistical methods used in previous analyses. The criticisms are reviewed in some detail and various new calculations and simulations, including one assessing the effects of paraphyletic taxa, are presented. Although the new data strengthen the case for periodicity, they offer little new insight into the deriving mechanism behind the pattern. However, they do suggest that many of the periodic events may not have been catastrophic, occurring instead over several stratigraphic stages or substages.

@article{doi101144gsjgs14610007,
    author = "Sepkoski, J. John",
    title = "Periodicity in extinction and the problem of catastrophism in the history of life",
    year = "1989",
    journal = "Journal of the Geological Society",
    abstract = "The hypothesis that extinction events have recurred periodically over the last quarter billion years is greatly strengthened by new data on the stratigraphic ranges of marine animal genera. In the interval from the Permian to Recent, these data encompass some 13,000 generic extinctions, providing a more sensitive indicator of species-level extinctions than previously used familial data. Extinction time series computed from the generic data display nine strong peaks that are nearly uniformly spaced at 26 Ma intervals over the last 270 Ma. Most of these peaks correspond to extinction events recognized in more detailed, if limited, biostratigraphic studies. These new data weaken or negate most arguments against periodicity, which have involved criticisms of the taxonomic data base, sampling intervals, chronometric time scales, and statistical methods used in previous analyses. The criticisms are reviewed in some detail and various new calculations and simulations, including one assessing the effects of paraphyletic taxa, are presented. Although the new data strengthen the case for periodicity, they offer little new insight into the deriving mechanism behind the pattern. However, they do suggest that many of the periodic events may not have been catastrophic, occurring instead over several stratigraphic stages or substages.",
    url = "https://doi.org/10.1144/gsjgs.146.1.0007",
    doi = "10.1144/gsjgs.146.1.0007",
    openalex = "W2122598889",
    references = "doi101029gl013i011p01177, doi101111j150239311977tb00628x, loper1988a"
}

@misc{alvarez1990iridium3,
    author = "Alvarez, W. and Asaro, F. and Montanari, A",
    title = "Iridium profile for 10 million years across the Cretaceous-Tertiary boundary at Gubbio (Italy)",
    year = "1990",
    howpublished = "Science, v. 250, no. 4988, p. 1700-1702",
    note = "talkorigins\_source = {true}; raw\_reference = {Alvarez, W., Asaro, F., and Montanari, A., 1990, Iridium profile for 10 million years across the Cretaceous-Tertiary boundary at Gubbio (Italy): Science, v. 250, no. 4988, p. 1700-1702.}"
}

Part 1 Almost all species are extinct: is extinction important? bad genes or bad luck? the nature of extinction who studies extinction? a word about the word species defined the purpose of extinction, if any. Part 2 A brief history of life: origin of life complex life the quality of the fossil record 600 million years of fussing a stock market analogy trilobite eyes tropical reefs flying reptiles human evolution living fossils. Part 3 Gambler's ruin and other problems: gambling concepts of randomness gambling for survival differing extinction and speciation rates skewed histograms other models a note on extinction of surnames. Part 4 Mass extinctions: the K-T mass extinction measuring extinction a note on killing duration of mass extinctions do mass extinctions differ from background the kill curve. Part 5 Selectivity of extinction: Ice Age Blitzkrieg selectivity of the Blitzkrieg body size and the K-T extinction other examples of bias other examples of selectivity the Trilobites' bad genes some implications summary. Part 6 The search for causes: the rarity of extinction just so stories beware of anthropomorphism! the kill curve revisited. Part 7 Biological causes of extinction: are species and ecosystems fragile? the case of the heath hen importance of the first strike problems of small populations competition species-area effects species-area and past extinctions the great American interchange the history of tropical rain forests. Part 8 Physical causes of extinction: traditional favourites sea level and climate species-area effects testing sea level and climate the Pleistocene experience exotic physical causes unheard-of volcanism cosmic causes. Part 9 Rocks falling out of the sky: cratering rates destructive power Alvarez and the K-T extinction periodicity of extinction and nemesis. Part 10 Could all the extinctions be caused by meteorite impact? plausibility arguments arguments from observation extinctions are linked to craters extinctions are not linked to craters assessment. Part 11 Perspectives on extinction: how to become extinct wanton extinction the role of extinction in evolution bad genes or bad luck? a note on extinctions today. Epilogue: did we choose a safe planet?.

@article{doi105860choice293880,
    author = "Raup, David M.",
    title = "Extinction: bad genes or bad luck?",
    year = "1992",
    journal = "Choice Reviews Online",
    abstract = "Part 1 Almost all species are extinct: is extinction important? bad genes or bad luck? the nature of extinction who studies extinction? a word about the word species defined the purpose of extinction, if any. Part 2 A brief history of life: origin of life complex life the quality of the fossil record 600 million years of fussing a stock market analogy trilobite eyes tropical reefs flying reptiles human evolution living fossils. Part 3 Gambler's ruin and other problems: gambling concepts of randomness gambling for survival differing extinction and speciation rates skewed histograms other models a note on extinction of surnames. Part 4 Mass extinctions: the K-T mass extinction measuring extinction a note on killing duration of mass extinctions do mass extinctions differ from background the kill curve. Part 5 Selectivity of extinction: Ice Age Blitzkrieg selectivity of the Blitzkrieg body size and the K-T extinction other examples of bias other examples of selectivity the Trilobites' bad genes some implications summary. Part 6 The search for causes: the rarity of extinction just so stories beware of anthropomorphism! the kill curve revisited. Part 7 Biological causes of extinction: are species and ecosystems fragile? the case of the heath hen importance of the first strike problems of small populations competition species-area effects species-area and past extinctions the great American interchange the history of tropical rain forests. Part 8 Physical causes of extinction: traditional favourites sea level and climate species-area effects testing sea level and climate the Pleistocene experience exotic physical causes unheard-of volcanism cosmic causes. Part 9 Rocks falling out of the sky: cratering rates destructive power Alvarez and the K-T extinction periodicity of extinction and nemesis. Part 10 Could all the extinctions be caused by meteorite impact? plausibility arguments arguments from observation extinctions are linked to craters extinctions are not linked to craters assessment. Part 11 Perspectives on extinction: how to become extinct wanton extinction the role of extinction in evolution bad genes or bad luck? a note on extinctions today. Epilogue: did we choose a safe planet?.",
    url = "https://doi.org/10.5860/choice.29-3880",
    doi = "10.5860/choice.29-3880",
    openalex = "W1599898647",
    references = "alvarez1980extraterrestrial, doi101017s0094837300004917, doi101017s009483730000508x, doi101017s0094837300005649, doi101038242032a0, doi101086627905, doi101126science2064415217, doi101126science20844481095, doi107312gumb92958, openalexw2145250129, openalexw3135630760"
}

Analysis of the end-Cretaceous mass extinction, based on 3514 occurrences of 340 genera of marine bivalves (Mollusca), suggests that extinction intensities were uniformly global; no latitudinal gradients or other geographic patterns are detected. Elevated extinction intensities in some tropical areas are entirely a result of the distribution of one extinct group of highly specialized bivalves, the rudists. When rudists are omitted, intensities at those localities are statistically indistinguishable from those of both the rudist-free tropics and extratropical localities.

@article{doi101126science11537491,
    author = "Raup, David M. and Jablonski, David",
    title = "Geography of End-Cretaceous Marine Bivalve Extinctions",
    year = "1993",
    journal = "Science",
    abstract = "Analysis of the end-Cretaceous mass extinction, based on 3514 occurrences of 340 genera of marine bivalves (Mollusca), suggests that extinction intensities were uniformly global; no latitudinal gradients or other geographic patterns are detected. Elevated extinction intensities in some tropical areas are entirely a result of the distribution of one extinct group of highly specialized bivalves, the rudists. When rudists are omitted, intensities at those localities are statistically indistinguishable from those of both the rudist-free tropics and extratropical localities.",
    url = "https://doi.org/10.1126/science.11537491",
    doi = "10.1126/science.11537491",
    openalex = "W1982304005",
    references = "doi101007bf02239720, doi101007bfb0011129, doi101017s0022336000029486, doi101029pa001i001p00005, doi101038359819a0, doi101126science2314734129, doi101126science2535021754, doi101130spe190p353, doi101144gsjgs14610007, doi1023073514530"
}

@article{doi1011300016760619931050979gmessa23co2,
    author = "Keller, Gerta and Barrera, Enriqueta and Schmitz, Benjamin and Mattson, EE",
    title = "Gradual mass extinction, species survivorship, and long-term environmental changes across the Cretaceous-Tertiary boundary in high latitudes",
    year = "1993",
    journal = "Geological Society of America Bulletin",
    url = "https://doi.org/10.1130/0016-7606(1993)105<0979:gmessa>2.3.co;2",
    doi = "10.1130/0016-7606(1993)105<0979:gmessa>2.3.co;2",
    openalex = "W1991351269"
}

The extinction of species is not normally considered an important element of neodarwinian theory, in contrast to the opposite phenomenon, speciation. This is surprising in view of the special importance Darwin attached to extinction, and because the number of species extinctions in the history of life is almost the same as the number of originations; present-day biodiversity is the result of a trivial surplus of originations, cumulated over millions of years. For an evolutionary biologist to ignore extinction is probably as foolhardy as for a demographer to ignore mortality. The past decade has seen a resurgence of interest in extinction, yet research on the topic is still at a reconnaissance level, and our present understanding of its role in evolution is weak. Despite uncertainties, extinction probably contains three important elements. (i) For geographically widespread species, extinction is likely only if the killing stress is one so rare as to be beyond the experience of the species, and thus outside the reach of natural selection. (ii) The largest mass extinctions produce major restructuring of the biosphere wherein some successful groups are eliminated, allowing previously minor groups to expand and diversify. (iii) Except for a few cases, there is little evidence that extinction is selective in the positive sense argued by Darwin. It has generally been impossible to predict, before the fact, which species will be victims of an extinction event.

@article{doi101073pnas91156758,
    author = "Raup, David M.",
    title = "The role of extinction in evolution.",
    year = "1994",
    journal = "Proceedings of the National Academy of Sciences",
    abstract = "The extinction of species is not normally considered an important element of neodarwinian theory, in contrast to the opposite phenomenon, speciation. This is surprising in view of the special importance Darwin attached to extinction, and because the number of species extinctions in the history of life is almost the same as the number of originations; present-day biodiversity is the result of a trivial surplus of originations, cumulated over millions of years. For an evolutionary biologist to ignore extinction is probably as foolhardy as for a demographer to ignore mortality. The past decade has seen a resurgence of interest in extinction, yet research on the topic is still at a reconnaissance level, and our present understanding of its role in evolution is weak. Despite uncertainties, extinction probably contains three important elements. (i) For geographically widespread species, extinction is likely only if the killing stress is one so rare as to be beyond the experience of the species, and thus outside the reach of natural selection. (ii) The largest mass extinctions produce major restructuring of the biosphere wherein some successful groups are eliminated, allowing previously minor groups to expand and diversify. (iii) Except for a few cases, there is little evidence that extinction is selective in the positive sense argued by Darwin. It has generally been impossible to predict, before the fact, which species will be victims of an extinction event.",
    url = "https://doi.org/10.1073/pnas.91.15.6758",
    doi = "10.1073/pnas.91.15.6758",
    openalex = "W2044668604",
    references = "doi101126science11537491"
}

Three tests based on fossil data indicate that high rates of extinction recorded in the penultimate (Guadalupian) stage of the Paleozoic era are not artifacts of a poor fossil record. Instead, they represent an abrupt mass extinction that was one of the largest to occur in the past half billion years. The final mass extinction of the era, which took place about 5 million years after the Guadalupian event, remains the most severe biotic crisis of all time. Taxonomic losses in the Late Permian were partitioned among the two crises and the intervening interval, however, and the terminal Permian crisis eliminated only about 80 percent of marine species, not 95 or 96 percent as earlier estimates have suggested.

@article{doi101126science26651891340,
    author = "Stanley, Steven M. and Yang, Xiu‐Qun",
    title = "A Double Mass Extinction at the End of the Paleozoic Era",
    year = "1994",
    journal = "Science",
    abstract = "Three tests based on fossil data indicate that high rates of extinction recorded in the penultimate (Guadalupian) stage of the Paleozoic era are not artifacts of a poor fossil record. Instead, they represent an abrupt mass extinction that was one of the largest to occur in the past half billion years. The final mass extinction of the era, which took place about 5 million years after the Guadalupian event, remains the most severe biotic crisis of all time. Taxonomic losses in the Late Permian were partitioned among the two crises and the intervening interval, however, and the terminal Permian crisis eliminated only about 80 percent of marine species, not 95 or 96 percent as earlier estimates have suggested.",
    url = "https://doi.org/10.1126/science.266.5189.1340",
    doi = "10.1126/science.266.5189.1340",
    openalex = "W1991491867",
    references = "doi1010079781489957603"
}

Paleoecologic study of invertebrate faunas from three successive Early Triassic seaways reveals that biotic recovery from the end-Permian mass extinction event was slow, and that full recovery did not occur until after the Early Triassic. Simple, cosmopolitan, opportunistic generalists, and low-diversity, low-complexity paleocommunities were characteristic of the entire Early Triassic in the Western USA. An increase in guild and taxonomic diversity was observed with the addition of several new higher taxa in the late Early Triassic (Spathian) to the almost exclusively molluscan faunas of the earlier Early Triassic (Nammalian). Potential “disaster forms” (the inarticulate brachiopod, Lingula, and the paper pecten, Claraia) dominated the earliest Early Triassic faunas (Griesbachian) and even occurred in the late Early Triassic (normal marine stromatolites). Comparison with data on faunas from the Permian and Triassic suggests that even the most diverse Early Triassic faunas (in the Spathian) were rather low in guild diversity and species richness. These characteristics of genera and paleocommunities in the Early Triassic may be typical of mass extinction aftermaths.

@article{doi101016003101829400093n,
    author = "Schubert, Jennifer K. and Bottjer, David J.",
    title = "Aftermath of the Permian-Triassic mass extinction event: Paleoecology of Lower Triassic carbonates in the western USA",
    year = "1995",
    journal = "Palaeogeography Palaeoclimatology Palaeoecology",
    abstract = "Paleoecologic study of invertebrate faunas from three successive Early Triassic seaways reveals that biotic recovery from the end-Permian mass extinction event was slow, and that full recovery did not occur until after the Early Triassic. Simple, cosmopolitan, opportunistic generalists, and low-diversity, low-complexity paleocommunities were characteristic of the entire Early Triassic in the Western USA. An increase in guild and taxonomic diversity was observed with the addition of several new higher taxa in the late Early Triassic (Spathian) to the almost exclusively molluscan faunas of the earlier Early Triassic (Nammalian). Potential “disaster forms” (the inarticulate brachiopod, Lingula, and the paper pecten, Claraia) dominated the earliest Early Triassic faunas (Griesbachian) and even occurred in the late Early Triassic (normal marine stromatolites). Comparison with data on faunas from the Permian and Triassic suggests that even the most diverse Early Triassic faunas (in the Spathian) were rather low in guild diversity and species richness. These characteristics of genera and paleocommunities in the Early Triassic may be typical of mass extinction aftermaths.",
    url = "https://doi.org/10.1016/0031-0182(94)00093-n",
    doi = "10.1016/0031-0182(94)00093-n",
    openalex = "W2061526312",
    references = "doi1010079781475707403, doi101007978364270831215, doi1010079783642758294, doi101007bfb0011152, doi1010160031018281900924, doi101017cbo9780511735769004, doi101017s0094837300011787, doi101038367231a0, doi101126science2164542173, doi101306212f89c22b2411d78648000102c1865d, doi1023071483846, doi1023072406301, doi1023072409086, doi105860choice295709, doi105860choice312127, openalexw1549886310, openalexw1590447055, openalexw2989049194"
}

Analyses of the end-Cretaceous or Cretaceous-Tertiary mass extinction show no selectivity of marine bivalve genera by life position (burrowing versus exposed), body size, bathymetric position on the continental shelf, or relative breadth of bathymetric range. Deposit-feeders as a group have significantly lower extinction intensities than suspension-feeders, but this pattern is due entirely to low extinction in two groups (Nuculoida and Lucinoidea), which suggests that survivorship was not simply linked to feeding mode. Geographically widespread genera have significantly lower extinction intensities than narrowly distributed genera. These results corroborate earlier work suggesting that some biotic factors that enhance survivorship during times of lesser extinction intensities are ineffectual during mass extinctions.

@article{doi101126science11536722,
    author = "Jablonski, D and Raup, D M",
    title = "Selectivity of end-Cretaceous marine bivalve extinctions.",
    year = "1995",
    journal = "Science (New York, N.Y.)",
    abstract = "Analyses of the end-Cretaceous or Cretaceous-Tertiary mass extinction show no selectivity of marine bivalve genera by life position (burrowing versus exposed), body size, bathymetric position on the continental shelf, or relative breadth of bathymetric range. Deposit-feeders as a group have significantly lower extinction intensities than suspension-feeders, but this pattern is due entirely to low extinction in two groups (Nuculoida and Lucinoidea), which suggests that survivorship was not simply linked to feeding mode. Geographically widespread genera have significantly lower extinction intensities than narrowly distributed genera. These results corroborate earlier work suggesting that some biotic factors that enhance survivorship during times of lesser extinction intensities are ineffectual during mass extinctions.",
    url = "https://pubmed.ncbi.nlm.nih.gov/11536722/",
    doi = "10.1126/science.11536722",
    openalex = "W2091645263",
    pmid = "11536722",
    references = "doi101017cbo9780511608551, doi101038365636a0, doi101038367231a0, doi101086284889, doi101086285558, doi101098rsta19900058, doi101098rsta19900060, doi101098rstb19940045, doi101126science11537491, doi101126science2314734129, doi1023073514444"
}

Analysis of the fossil record of microbes, algae, fungi, protists, plants, and animals shows that the diversity of both marine and continental life increased exponentially since the end of the Precambrian. This diversification was interrupted by mass extinctions, the largest of which occurred in the Early Cambrian, Late Ordovician, Late Devonian, Late Permian, Early Triassic, Late Triassic, and end-Cretaceous. Most of these extinctions were experienced by both marine and continental organisms. As for the periodicity of mass extinctions, no support was found: Seven mass extinction peaks in the last 250 million years are spaced 20 to 60 million years apart.

@article{doi101126science7701342,
    author = "Benton, Michael J.",
    title = "Diversification and Extinction in the History of Life",
    year = "1995",
    journal = "Science",
    abstract = "Analysis of the fossil record of microbes, algae, fungi, protists, plants, and animals shows that the diversity of both marine and continental life increased exponentially since the end of the Precambrian. This diversification was interrupted by mass extinctions, the largest of which occurred in the Early Cambrian, Late Ordovician, Late Devonian, Late Permian, Early Triassic, Late Triassic, and end-Cretaceous. Most of these extinctions were experienced by both marine and continental organisms. As for the periodicity of mass extinctions, no support was found: Seven mass extinction peaks in the last 250 million years are spaced 20 to 60 million years apart.",
    url = "https://doi.org/10.1126/science.7701342",
    doi = "10.1126/science.7701342",
    openalex = "W2010154591",
    references = "doi1010029781444313918, doi101017s0094837300005972, doi101017s0094837300006539, doi101017s0094837300008186, doi101038293435a0, doi101038303614a0, doi101073pnas813801, doi101111j109600311988tb00514x, doi101111j155856461987tb02459x, doi101126science11536548, doi101126science13334591105, doi101126science17740541065, doi101126science21545391501, doi101126science2605108640, doi1023072409086, doi105860choice284524, openalexw1599677799, openalexw2989049194"
}

Data on rocks from Spitsbergen and the equatorial sections of Italy and Slovenia indicate that the world's oceans became anoxic at both low and high paleolatitudes in the Late Permian. Such conditions may have been responsible for the mass extinction at this time. This event affected a wide range of shelf depths and extended into shallow water well above the storm wave base.

@article{doi101126science27252651155,
    author = "Wignall, Paul B. and Twitchett, Richard J.",
    title = "Oceanic Anoxia and the End Permian Mass Extinction",
    year = "1996",
    journal = "Science",
    abstract = "Data on rocks from Spitsbergen and the equatorial sections of Italy and Slovenia indicate that the world's oceans became anoxic at both low and high paleolatitudes in the Late Permian. Such conditions may have been responsible for the mass extinction at this time. This event affected a wide range of shelf depths and extended into shallow water well above the storm wave base.",
    url = "https://doi.org/10.1126/science.272.5265.1155",
    doi = "10.1126/science.272.5265.1155",
    openalex = "W1994510458",
    references = "doi1010160016703792903086, doi1010160031018292901825, doi101016003101829390068t, doi10102994pa01455, doi101126science26651891340, doi101126science267519477, doi101126science26952291413, doi1013060bda5a8916bd11d78645000102c1865d, doi101306212f89c22b2411d78648000102c1865d, doi1015159781400855414"
}

The repeated association during the late Neoproterozoic Era of large carbon-isotopic excursions, continental glaciation, and stratigraphically anomalous carbonate precipitation provides a framework for interpreting the reprise of these conditions on the Late Permian Earth. A paleoceanographic model that was developed to explain these stratigraphically linked phenomena suggests that the overturn of anoxic deep oceans during the Late Permian introduced high concentrations of carbon dioxide into surficial environments. The predicted physiological and climatic consequences for marine and terrestrial organisms are in good accord with the observed timing and selectivity of Late Permian mass extinction.

@article{doi101126science2735274452,
    author = "Knoll, Andrew H. and Bambach, Richard K. and Canfield, Donald E. and Grotzinger, J. P.",
    title = "Comparative Earth History and Late Permian Mass Extinction",
    year = "1996",
    journal = "Science",
    abstract = "The repeated association during the late Neoproterozoic Era of large carbon-isotopic excursions, continental glaciation, and stratigraphically anomalous carbonate precipitation provides a framework for interpreting the reprise of these conditions on the Late Permian Earth. A paleoceanographic model that was developed to explain these stratigraphically linked phenomena suggests that the overturn of anoxic deep oceans during the Late Permian introduced high concentrations of carbon dioxide into surficial environments. The predicted physiological and climatic consequences for marine and terrestrial organisms are in good accord with the observed timing and selectivity of Late Permian mass extinction.",
    url = "https://doi.org/10.1126/science.273.5274.452",
    doi = "10.1126/science.273.5274.452",
    openalex = "W2042526900",
    references = "doi1010160031018284900415, doi1010160301926894000708, doi101038367231a0, doi101111j150239311993tb01799x, doi101126science2064415217"
}

Abstract Mass extinction intervals are characterized by three dynamic processes: extinction, survival, and recovery. It has been assumed that the taxa surviving a mass extinction are composed predominantly of eurytopic groups and opportunistic/disaster species. However, high-resolution stratigraphic and palaeontological analyses of several mass extinction intervals show that the repopulation of the global ecosystem takes place among ecologically and genetically diverse and complex taxa and occurs far too rapidly to be solely attributed to rapid radiation from a few ecological generalists. We suggest a number of potential survival mechanisms or strategies (sensu Fryxell 1983) which have evolved in diverse taxa and which could have allowed them to survive mass extinction intervals. These mechanisms consist of: rapid evolution, preadaptation, neoteny/progenesis, protected and/or unperturbed habitat, refugia species, disaster species, opportunism, broad adaptive ranges, persistent trophic resources, widespread and rapid dispersion, dormancy, bacterial-chemosymbioses, skeletonization requirements, reproductive mechanisms, larval characteristics and chance. Because of the wide variety of potential survival mechanisms, the range of survivors may be far higher than previously hypothesized. This would account, in part, for the diversity and evolutionary state of Lazarus taxa and for the rapid re-establishment of some complex ecosystems following many mass extinction intervals, without calling on “explosive” radiation from generalist/opportunist stocks following a mass extinction interval.

@article{doi101144gslsp19960010103,
    author = "Harries, Peter J. and Kauffman, Erle G. and Hansen, Thor A.",
    title = "Models for biotic survival following mass extinction",
    year = "1996",
    journal = "Geological Society London Special Publications",
    abstract = "Abstract Mass extinction intervals are characterized by three dynamic processes: extinction, survival, and recovery. It has been assumed that the taxa surviving a mass extinction are composed predominantly of eurytopic groups and opportunistic/disaster species. However, high-resolution stratigraphic and palaeontological analyses of several mass extinction intervals show that the repopulation of the global ecosystem takes place among ecologically and genetically diverse and complex taxa and occurs far too rapidly to be solely attributed to rapid radiation from a few ecological generalists. We suggest a number of potential survival mechanisms or strategies (sensu Fryxell 1983) which have evolved in diverse taxa and which could have allowed them to survive mass extinction intervals. These mechanisms consist of: rapid evolution, preadaptation, neoteny/progenesis, protected and/or unperturbed habitat, refugia species, disaster species, opportunism, broad adaptive ranges, persistent trophic resources, widespread and rapid dispersion, dormancy, bacterial-chemosymbioses, skeletonization requirements, reproductive mechanisms, larval characteristics and chance. Because of the wide variety of potential survival mechanisms, the range of survivors may be far higher than previously hypothesized. This would account, in part, for the diversity and evolutionary state of Lazarus taxa and for the rapid re-establishment of some complex ecosystems following many mass extinction intervals, without calling on “explosive” radiation from generalist/opportunist stocks following a mass extinction interval.",
    url = "https://doi.org/10.1144/gsl.sp.1996.001.01.03",
    doi = "10.1144/gsl.sp.1996.001.01.03",
    openalex = "W2062966131",
    references = "doi101007bfb0011152, doi101111j1469185x1973tb00979x, doi102110pec74200094"
}

Abstract Why do mass extinctions occur? The demise of the dinosaurs has been discussed exhaustively, but has never been out into the context of other extinction events. This is the first systematic review of the mass extinctions of all organisms, plant and animal, terrestrial and marine, that have occurred in the history of life. This includes the major crisis 250 million years ago which nearly wiped out all life on Earth. By examining current paleontological, geological, and sedimentological evidence of environmental changes, the cases for explanations based on climate change, marine regressions, asteroid or comet impact, anoxia, and volcanic eruptions are all critically evaluated.

@book{doi101093oso97801985491780010001,
    author = "Hallam, A. and Wignall, Paul B.",
    title = "Mass Extinctions and Their Aftermath",
    year = "1997",
    abstract = "Abstract Why do mass extinctions occur? The demise of the dinosaurs has been discussed exhaustively, but has never been out into the context of other extinction events. This is the first systematic review of the mass extinctions of all organisms, plant and animal, terrestrial and marine, that have occurred in the history of life. This includes the major crisis 250 million years ago which nearly wiped out all life on Earth. By examining current paleontological, geological, and sedimentological evidence of environmental changes, the cases for explanations based on climate change, marine regressions, asteroid or comet impact, anoxia, and volcanic eruptions are all critically evaluated.",
    url = "https://doi.org/10.1093/oso/9780198549178.001.0001",
    doi = "10.1093/oso/9780198549178.001.0001",
    openalex = "W4388328712"
}

Mass extinctions are recognized through the study of fossil groups across event horizons, and from analyses of long-term trends in taxonomic richness and diversity. Both approaches have inherent flaws, and data that once seemed reliable can be readily superseded by the discovery of new fossils and/or the application of new analytical techniques. Herein the current state of the Cretaceous-Tertiary (K-T) biostratigraphical record is reviewed for most major fossil clades, including: calcareous nannoplankton, dinoflagellates, diatoms, radiolaria, foraminifera, ostracodes, scleractinian corals, bryozoans, brachio-pods, molluscs, echinoderms, fish, amphibians, reptiles and terrestrial plants (macrofossils and palynomorphs). These reviews take account of possible biasing factors in the fossil record in order to extract the most comprehensive picture of the K-T biotic crisis available. Results suggest that many faunal and floral groups (ostracodes, bryozoa, ammonite cephalopods, bivalves, archosaurs) were in decline throughout the latest Maastrichtian while others (diatoms, radiolaria, benthic foraminifera, brachiopods, gastropods, fish, amphibians, lepidosaurs, terrestrial plants) passed through the K-T event horizon with only minor taxonomic richness and/or diversity changes. A few microfossil groups (calcareous nannoplankton, dinoflagellates, planktonic foraminifera) did experience a turnover of varying magnitudes in the latest Maastrichtian-earliest Danian. However, many of these turnovers, along with changes in ecological dominance patterns among benthic foraminifera, began in the latest Maastrichtian. Improved taxonomic estimates of the overall pattern and magnitude of the K-T extinction event must await the development of more reliable systematic and phylogenetic data for all Upper Cretaceous clades.

@article{doi101144gsjgs15420265,
    author = "MacLeod, Norman and Rawson, Peter F. and Forey, Peter L. and Banner, F. T. and BouDagher‐Fadel, Marcelle K. and Bown, Paul R. and Burnett, J. A. and Chambers, Paul and Culver, Stephen J. and Evans, Susan E. and Jeffery, C. S. and Kaminski, Michael A. and Lord, Alan and MILNER, A. C. and Milner, Andrew R. and Morris, Noel J. and Owen, Ellie and Rosen, Brian and Smith, A. B. and Taylor, Paul D. and Urquhart, Elspeth and Young, J. R.",
    title = "The Cretaceous-Tertiary biotic transition",
    year = "1997",
    journal = "Journal of the Geological Society",
    abstract = "Mass extinctions are recognized through the study of fossil groups across event horizons, and from analyses of long-term trends in taxonomic richness and diversity. Both approaches have inherent flaws, and data that once seemed reliable can be readily superseded by the discovery of new fossils and/or the application of new analytical techniques. Herein the current state of the Cretaceous-Tertiary (K-T) biostratigraphical record is reviewed for most major fossil clades, including: calcareous nannoplankton, dinoflagellates, diatoms, radiolaria, foraminifera, ostracodes, scleractinian corals, bryozoans, brachio-pods, molluscs, echinoderms, fish, amphibians, reptiles and terrestrial plants (macrofossils and palynomorphs). These reviews take account of possible biasing factors in the fossil record in order to extract the most comprehensive picture of the K-T biotic crisis available. Results suggest that many faunal and floral groups (ostracodes, bryozoa, ammonite cephalopods, bivalves, archosaurs) were in decline throughout the latest Maastrichtian while others (diatoms, radiolaria, benthic foraminifera, brachiopods, gastropods, fish, amphibians, lepidosaurs, terrestrial plants) passed through the K-T event horizon with only minor taxonomic richness and/or diversity changes. A few microfossil groups (calcareous nannoplankton, dinoflagellates, planktonic foraminifera) did experience a turnover of varying magnitudes in the latest Maastrichtian-earliest Danian. However, many of these turnovers, along with changes in ecological dominance patterns among benthic foraminifera, began in the latest Maastrichtian. Improved taxonomic estimates of the overall pattern and magnitude of the K-T extinction event must await the development of more reliable systematic and phylogenetic data for all Upper Cretaceous clades.",
    url = "https://doi.org/10.1144/gsjgs.154.2.0265",
    doi = "10.1144/gsjgs.154.2.0265",
    openalex = "W2111194718",
    references = "alvarez1980extraterrestrial, doi1010160377839888900023, doi101017s0022336000029486, doi101017s0022336000061321, doi101017s0022336000062223, doi101073pnas813801, doi101111j136531211990tb00103x, doi101126science20844481095, doi101126science23547931156, doi1011300016760619951071164mlccot23co2, doi101130spe190p291, doi1012019781003077831, doi102110pec9504, doi102110pec95040129, doi1023071483846, doi1023072259561, doi1023073514632, kier1974evolutionary, kitchell1986biological, kitchellNonebiological, openalexw1599677799, sloan1986gradual"
}

The discovery of a fish bone layer immediately overlying the K-T iridium anomaly on Seymour Island, Antarctic Peninsula, which may represent the first documented mass kill associated with the impact event, together with new faunal data across the boundary has provided new insight into events at the end of the Cretaceous. The utilization of a geographical approach and a new graphical representation of range data has revealed that events at the end of the Cretaceous were not instantaneous, but occurred over a finite period of time. Although the fish bone layer may contain victims of the impact event, the absence of ammonites in either the iridiumbearing layer or the overlying fish layer suggests that the extinction event at the end of the Cretaceous was the culmination of several processes beginning in the late Campanian. The impact was the proverbial “straw that broke the camel's back,” leading to the extinction of many others forms of life that might have survived the period of global biotic stress during the waning stages of the Mesozoic if there had not been an impact. The absence of mass extinction following catastrophic geologic events in a biotic robust world, such as the Middle Ordovician Millbrig-Big Bentonite volcanic event suggests that the biosphere is remarkably resilient to major geologic catastrophes with mass extinction events occurring only when there is a conjunction of geologic events none of which might be capable of producing a global mass extinction by itself.

@article{doi101017s0022336000024331,
    author = "Zinsmeister, William J.",
    title = "Discovery of fish mortality horizon at the K-T Boundary on Seymour Island: Re-evaluation of events at the end of the Cretaceous",
    year = "1998",
    journal = "Journal of Paleontology",
    abstract = "The discovery of a fish bone layer immediately overlying the K-T iridium anomaly on Seymour Island, Antarctic Peninsula, which may represent the first documented mass kill associated with the impact event, together with new faunal data across the boundary has provided new insight into events at the end of the Cretaceous. The utilization of a geographical approach and a new graphical representation of range data has revealed that events at the end of the Cretaceous were not instantaneous, but occurred over a finite period of time. Although the fish bone layer may contain victims of the impact event, the absence of ammonites in either the iridiumbearing layer or the overlying fish layer suggests that the extinction event at the end of the Cretaceous was the culmination of several processes beginning in the late Campanian. The impact was the proverbial “straw that broke the camel's back,” leading to the extinction of many others forms of life that might have survived the period of global biotic stress during the waning stages of the Mesozoic if there had not been an impact. The absence of mass extinction following catastrophic geologic events in a biotic robust world, such as the Middle Ordovician Millbrig-Big Bentonite volcanic event suggests that the biosphere is remarkably resilient to major geologic catastrophes with mass extinction events occurring only when there is a conjunction of geologic events none of which might be capable of producing a global mass extinction by itself.",
    url = "https://doi.org/10.1017/s0022336000024331",
    doi = "10.1017/s0022336000024331",
    openalex = "W2415897593",
    references = "doi101007bf00897326, doi1010160012825272900724, doi101130001676061971823325ptmfte20co2, doi1011300091761319920200875govafi23co2, doi101130spe190p291, doi101306c1ea55ad16c911d78645000102c1865d, doi1023071794238, doi1023073514978, doi107203sjp25159, openalexw2520801884, openalexw589829769"
}

The mass extinction at the end of the Permian was the most profound in the history of life. Fundamental to understanding its cause is determining the tempo and duration of the extinction. Uranium/lead zircon data from Late Permian and Early Triassic rocks from south China place the Permian-Triassic boundary at 251.4 +/- 0.3 million years ago. Biostratigraphic controls from strata intercalated with ash beds below the boundary indicate that the Changhsingian pulse of the end-Permian extinction, corresponding to the disappearance of about 85 percent of marine species, lasted less than 1 million years. At Meishan, a negative excursion in delta13C at the boundary had a duration of 165,000 years or less, suggesting a catastrophic addition of light carbon.

@article{doi101126science28053661039,
    author = "Bowring, S.A. and Erwin, Douglas H. and Jin, Yuxi and MARTIN, MARK W. and Davidek, Kathleen L. and Wang, Wei",
    title = "U/Pb Zircon Geochronology and Tempo of the End-Permian Mass Extinction",
    year = "1998",
    journal = "Science",
    abstract = "The mass extinction at the end of the Permian was the most profound in the history of life. Fundamental to understanding its cause is determining the tempo and duration of the extinction. Uranium/lead zircon data from Late Permian and Early Triassic rocks from south China place the Permian-Triassic boundary at 251.4 +/- 0.3 million years ago. Biostratigraphic controls from strata intercalated with ash beds below the boundary indicate that the Changhsingian pulse of the end-Permian extinction, corresponding to the disappearance of about 85 percent of marine species, lasted less than 1 million years. At Meishan, a negative excursion in delta13C at the boundary had a duration of 165,000 years or less, suggesting a catastrophic addition of light carbon.",
    url = "https://doi.org/10.1126/science.280.5366.1039",
    doi = "10.1126/science.280.5366.1039",
    openalex = "W1987227930",
    references = "doi1010160031018293901286, doi101016s0031018297000503, doi101038367231a0"
}

@article{doi101016s0031018299000863,
    author = "Harries, Peter J. and Little, Crispin T. S.",
    title = "The early Toarcian (Early Jurassic) and the Cenomanian–Turonian (Late Cretaceous) mass extinctions: similarities and contrasts",
    year = "1999",
    journal = "Palaeogeography Palaeoclimatology Palaeoecology",
    url = "https://doi.org/10.1016/s0031-0182(99)00086-3",
    doi = "10.1016/s0031-0182(99)00086-3",
    openalex = "W2023121856",
    references = "doi1010079783642758294, doi101007bfb0011152, doi1010160195667188900031, doi101017cbo9780511628948, doi101017s0094837300008708, doi101073pnas813801, doi10113000917613198614535scaia20co2, doi1011300091761319950230495ejmeag23co2, doi101130spe247, doi101146annurevea22050194002435, doi1013060c9b232b171011d78645000102c1865d, doi1013062f91892d16ce11d78645000102c1865d, doi102110pec88010071, doi102475ajs2882101, doi105860choice273873, doi107203sjp25159, openalexw2989049194, openalexw658437845"
}

This is a systematic review of the major mass extinctions in the history of life. It covers all groups of organisms - plant, animal, terrestrial, and marine - that have become extinct alongside the geological and sedimentological evidence for environmental changes during the biotic crises. All proposed extinction mechanisms - climate change, meteorite impact, volcanisms - are critically assessed. In this text the demise of the dinosaurs is put into the proper context of other extinction events. This book is intended for undergraduates in Europe and graduate students in the US, studying geology, palaeontology, or evolutionary biology, and their teachers. It should also be of interest to research scientists in adjacent subjects.

@article{doi1023073515466,
    author = "Marshall, Charles R. and Hallam, A. and Wignall, Paul B.",
    title = "Mass Extinctions and Their Aftermath",
    year = "1999",
    journal = "Palaios",
    abstract = "This is a systematic review of the major mass extinctions in the history of life. It covers all groups of organisms - plant, animal, terrestrial, and marine - that have become extinct alongside the geological and sedimentological evidence for environmental changes during the biotic crises. All proposed extinction mechanisms - climate change, meteorite impact, volcanisms - are critically assessed. In this text the demise of the dinosaurs is put into the proper context of other extinction events. This book is intended for undergraduates in Europe and graduate students in the US, studying geology, palaeontology, or evolutionary biology, and their teachers. It should also be of interest to research scientists in adjacent subjects.",
    url = "https://doi.org/10.2307/3515466",
    doi = "10.2307/3515466",
    openalex = "W2025737227"
}

The Meishan section across the Permian-Triassic boundary in South China is the most thoroughly investigated in the world. A statistical analysis of the occurrences of 162 genera and 333 species confirms a sudden extinction event at 251.4 million years ago, coincident with a dramatic depletion of delta13C(carbonate) and an increase in microspherules.

@article{doi101126science2895478432,
    author = "Jin, Y. G. and Wang, Y. and Wang, Wei and Shang, Qiangyu and Cao, Changqun and Erwin, Douglas H.",
    title = "Pattern of Marine Mass Extinction Near the Permian-Triassic Boundary in South China",
    year = "2000",
    journal = "Science",
    abstract = "The Meishan section across the Permian-Triassic boundary in South China is the most thoroughly investigated in the world. A statistical analysis of the occurrences of 162 genera and 333 species confirms a sudden extinction event at 251.4 million years ago, coincident with a dramatic depletion of delta13C(carbonate) and an increase in microspherules.",
    url = "https://doi.org/10.1126/science.289.5478.432",
    doi = "10.1126/science.289.5478.432",
    openalex = "W2090254843"
}

Although mass extinctions probably account for the disappearance of less than 5% of all extinct species, the evolutionary opportunities they have created have had a disproportionate effect on the history of life. Theoretical considerations and simulations have suggested that the empty niches created by a mass extinction should refill rapidly after extinction ameliorates. Under logistic models, this biotic rebound should be exponential, slowing as the environmental carrying capacity is approached. Empirical studies reveal a more complex dynamic, including positive feedback and an exponential growth phase during recoveries. Far from a model of refilling ecospace, mass extinctions appear to cause a collapse of ecospace, which must be rebuilt during recovery. Other generalities include the absence of a clear correlation between the magnitude of extinction and the pace of recovery or the resulting ecological and evolutionary disruption the presence of a survival interval, with few originations, immediately after an extinction and preceding the recovery phase, and the presence of many lineages that persist through an extinction event only to disappear during the subsequent recovery. Several recoveries include numerous missing lineages, groups that are found before the extinction, then latter in the recovery, but are missing during the initial survival-recovery phase. The limited biogeographic studies of recoveries suggest considerable variability between regions.

@article{doi101073pnas091092698,
    author = "Erwin, Douglas H.",
    title = "Lessons from the past: Biotic recoveries from mass extinctions",
    year = "2001",
    journal = "Proceedings of the National Academy of Sciences",
    abstract = "Although mass extinctions probably account for the disappearance of less than 5\% of all extinct species, the evolutionary opportunities they have created have had a disproportionate effect on the history of life. Theoretical considerations and simulations have suggested that the empty niches created by a mass extinction should refill rapidly after extinction ameliorates. Under logistic models, this biotic rebound should be exponential, slowing as the environmental carrying capacity is approached. Empirical studies reveal a more complex dynamic, including positive feedback and an exponential growth phase during recoveries. Far from a model of refilling ecospace, mass extinctions appear to cause a collapse of ecospace, which must be rebuilt during recovery. Other generalities include the absence of a clear correlation between the magnitude of extinction and the pace of recovery or the resulting ecological and evolutionary disruption the presence of a survival interval, with few originations, immediately after an extinction and preceding the recovery phase, and the presence of many lineages that persist through an extinction event only to disappear during the subsequent recovery. Several recoveries include numerous missing lineages, groups that are found before the extinction, then latter in the recovery, but are missing during the initial survival-recovery phase. The limited biogeographic studies of recoveries suggest considerable variability between regions.",
    url = "https://doi.org/10.1073/pnas.091092698",
    doi = "10.1073/pnas.091092698",
    openalex = "W2101625633",
    references = "doi101002sici1099103419991112344321aidgj80930co2i, doi101007bfb0011152, doi101016003101829400093n, doi101016s0012825297834848, doi101016s0031018299000863, doi101017s0094837300011787, doi101038324148a0, doi101098rstb19890092, doi101126science2825387276, openalexw658437845"
}

Mass extinctions have played many evolutionary roles, involving differential survivorship or selectivity of taxa and traits, the disruption or preservation of evolutionary trends and ecosystem organization, and the promotion of taxonomic and morphological diversifications-often along unexpected trajectories-after the destruction or marginalization of once-dominant clades. The fossil record suggests that survivorship during mass extinctions is not strictly random, but it often fails to coincide with factors promoting survival during times of low extinction intensity. Although of very serious concern, present-day extinctions have not yet achieved the intensities seen in the Big Five mass extinctions of the geologic past, which each removed > or =50% of the subset of relatively abundant marine invertebrate genera. The best comparisons for predictive purposes therefore will involve factors such as differential extinction intensities among regions, clades, and functional groups, rules governing postextinction biotic interchanges and evolutionary dynamics, and analyses of the factors that cause taxa and evolutionary trends to continue unabated, to suffer setbacks but resume along the same trajectory, to survive only to fall into a marginal role or disappear ("dead clade walking"), or to undergo a burst of diversification. These issues need to be addressed in a spatially explicit framework, because the fossil record suggests regional differences in postextinction diversification dynamics and biotic interchanges. Postextinction diversifications lag far behind the initial taxonomic and morphological impoverishment and homogenization; they do not simply reoccupy vacated adaptive peaks, but explore opportunities as opened and constrained by intrinsic biotic factors and the ecological and evolutionary context of the radiation.

@article{doi101073pnas101092598,
    author = "Jablonski, David",
    title = "Lessons from the past: Evolutionary impacts of mass extinctions",
    year = "2001",
    journal = "Proceedings of the National Academy of Sciences",
    abstract = {Mass extinctions have played many evolutionary roles, involving differential survivorship or selectivity of taxa and traits, the disruption or preservation of evolutionary trends and ecosystem organization, and the promotion of taxonomic and morphological diversifications-often along unexpected trajectories-after the destruction or marginalization of once-dominant clades. The fossil record suggests that survivorship during mass extinctions is not strictly random, but it often fails to coincide with factors promoting survival during times of low extinction intensity. Although of very serious concern, present-day extinctions have not yet achieved the intensities seen in the Big Five mass extinctions of the geologic past, which each removed > or =50\% of the subset of relatively abundant marine invertebrate genera. The best comparisons for predictive purposes therefore will involve factors such as differential extinction intensities among regions, clades, and functional groups, rules governing postextinction biotic interchanges and evolutionary dynamics, and analyses of the factors that cause taxa and evolutionary trends to continue unabated, to suffer setbacks but resume along the same trajectory, to survive only to fall into a marginal role or disappear ("dead clade walking"), or to undergo a burst of diversification. These issues need to be addressed in a spatially explicit framework, because the fossil record suggests regional differences in postextinction diversification dynamics and biotic interchanges. Postextinction diversifications lag far behind the initial taxonomic and morphological impoverishment and homogenization; they do not simply reoccupy vacated adaptive peaks, but explore opportunities as opened and constrained by intrinsic biotic factors and the ecological and evolutionary context of the radiation.},
    url = "https://doi.org/10.1073/pnas.101092598",
    doi = "10.1073/pnas.101092598",
    openalex = "W2156141983",
    references = "doi10100797830311485211, doi101007s100219900049, doi101016s0031018299000887, doi101016s0169534798013639, doi101016s0169534799016791, doi101017s0094837300008186, doi101017s0094837300011787, doi10103835002501, doi101098rstb19980213, doi101126science2695222347, doi101146annurevecolsys281129, doi101146annurevecolsys281495, doi1023073514632, doi105860choice343307, doi105860choice344488, kitchell1986biological, witmer1991biomechanics"
}

The mass extinction that occurred at the end of the Permian period, 250 million years ago, was the most devastating loss of life that Earth has ever experienced. It is estimated that ca. 96% of marine species were wiped out and land plants, reptiles, amphibians and insects also suffered. The causes of this catastrophic event are currently a topic of intense debate. The geological record points to significant environmental disturbances, for example, global warming and stagnation of ocean water. A key issue is whether the Earth's feedback mechanisms can become unstable on their own, or whether some forcing is required to precipitate a catastrophe of this magnitude. A prime suspect for pushing Earth's systems into a critical condition is massive end-Permian Siberian volcanism, which would have pumped large quantities of carbon dioxide and toxic gases into the atmosphere. Recently, it has been postulated that Earth was also the victim of a bolide impact at this time. If further research substantiates this claim, it raises some intriguing questions. The Cretaceous-Tertiary mass extinction, 65 million years ago, was contemporaneous with both an impact and massive volcanism. Are both types of calamity necessary to drive Earth to the brink of faunal cataclysm? We do not presently have enough pieces of the jigsaw to solve the mystery of the end-Permian extinction, but the forensic work continues.

@article{doi101098rsta20021097,
    author = "White, Rosalind V",
    title = "Earth's biggest 'whodunnit': unravelling the clues in the case of the end-Permian mass extinction.",
    year = "2002",
    journal = "Philosophical transactions. Series A, Mathematical, physical, and engineering sciences",
    abstract = "The mass extinction that occurred at the end of the Permian period, 250 million years ago, was the most devastating loss of life that Earth has ever experienced. It is estimated that ca. 96\% of marine species were wiped out and land plants, reptiles, amphibians and insects also suffered. The causes of this catastrophic event are currently a topic of intense debate. The geological record points to significant environmental disturbances, for example, global warming and stagnation of ocean water. A key issue is whether the Earth's feedback mechanisms can become unstable on their own, or whether some forcing is required to precipitate a catastrophe of this magnitude. A prime suspect for pushing Earth's systems into a critical condition is massive end-Permian Siberian volcanism, which would have pumped large quantities of carbon dioxide and toxic gases into the atmosphere. Recently, it has been postulated that Earth was also the victim of a bolide impact at this time. If further research substantiates this claim, it raises some intriguing questions. The Cretaceous-Tertiary mass extinction, 65 million years ago, was contemporaneous with both an impact and massive volcanism. Are both types of calamity necessary to drive Earth to the brink of faunal cataclysm? We do not presently have enough pieces of the jigsaw to solve the mystery of the end-Permian extinction, but the forensic work continues.",
    url = "https://pubmed.ncbi.nlm.nih.gov/12626276/",
    doi = "10.1098/rsta.2002.1097",
    openalex = "W2023224274",
    pmid = "12626276",
    references = "alvarez1980extraterrestrial, doi1010160009254180900479, doi101016s0012825200000374, doi101017s0094837300008186, doi101038367231a0, doi101093oso97801985491780010001, doi101126science21545391501, doi101126science27252651155, doi101144gslmem19900120101, doi1023073515466"
}

This volume contains extended abstracts that have been accepted for presentation at the conference on Catastrophic Events and Mass Extinctions: Impacts and Beyond, July 9-12, 2000, in Vienna, Austria.

@book{doi101130spe356,
    author = "Koeberl, Christian and MacLeod, Kenneth G.",
    title = "Catastrophic events and mass extinctions: impacts and beyond",
    year = "2002",
    booktitle = "Geological Society of America eBooks",
    abstract = "This volume contains extended abstracts that have been accepted for presentation at the conference on Catastrophic Events and Mass Extinctions: Impacts and Beyond, July 9-12, 2000, in Vienna, Austria.",
    url = "https://doi.org/10.1130/spe356",
    doi = "10.1130/spe356",
    openalex = "W424210255",
    references = "doi101007bfb0011143, doi1010160012825283900223, doi101126science892320559"
}

@article{doi101016s0031018204004213,
    author = "Kiessling, Wolfgang and Baron‐Szabo, Rosemarie C.",
    title = "Extinction and recovery patterns of scleractinian corals at the Cretaceous-Tertiary boundary",
    year = "2004",
    journal = "Palaeogeography Palaeoclimatology Palaeoecology",
    url = "https://doi.org/10.1016/s0031-0182(04)00421-3",
    doi = "10.1016/s0031-0182(04)00421-3",
    openalex = "W2021506750",
    references = "doi101007bf02536880"
}

High-resolution carbon isotope measurements of multiple stratigraphic sections in south China demonstrate that the pronounced carbon isotopic excursion at the Permian-Triassic boundary was not an isolated event but the first in a series of large fluctuations that continued throughout the Early Triassic before ending abruptly early in the Middle Triassic. The unusual behavior of the carbon cycle coincides with the delayed recovery from end-Permian extinction recorded by fossils, suggesting a direct relationship between Earth system function and biological rediversification in the aftermath of Earth's most devastating mass extinction.

@article{doi101126science1097023,
    author = "Payne, Jonathan L. and Lehrmann, Daniel J. and Wei, Jiayong and Orchard, Michael J. and Schrag, Daniel P. and Knoll, Andrew H.",
    title = "Large Perturbations of the Carbon Cycle During Recovery from the End-Permian Extinction",
    year = "2004",
    journal = "Science",
    abstract = "High-resolution carbon isotope measurements of multiple stratigraphic sections in south China demonstrate that the pronounced carbon isotopic excursion at the Permian-Triassic boundary was not an isolated event but the first in a series of large fluctuations that continued throughout the Early Triassic before ending abruptly early in the Middle Triassic. The unusual behavior of the carbon cycle coincides with the delayed recovery from end-Permian extinction recorded by fossils, suggesting a direct relationship between Earth system function and biological rediversification in the aftermath of Earth's most devastating mass extinction.",
    url = "https://doi.org/10.1126/science.1097023",
    doi = "10.1126/science.1097023",
    openalex = "W2130869324",
    references = "doi101016003101829400093n, doi101016s0012821x03003479, doi101016s0012825202001046, doi101017s0016756800007603, doi10102995pa02087, doi101073pnas032095199, doi101126science2064415217, doi101126science2735274452, doi101126science28053661039, doi101126science2895478432, doi1011300016760619961080195gcgbpt23co2"
}

In post-Cambrian time, five events-the end-Ordovician, end-Frasnian in the Late Devonian, end-Permian, end-Triassic, and end-Cretaceous-are commonly grouped as the "big five" global intervals of mass extinction. Plotted by magnitude, extinction intensities for all Phanerozoic substages show a continuous distribution, with the five traditionally recognized mass extinctions located in the upper tail. Plotted by time, however, proportional extinctions clearly divide the Phanerozoic Eon into six stratigraphically coherent intervals of alternating high and low extinction intensity. These stratigraphic neighborhoods provide a temporal context for evaluating the intensity of extinction during the "big five" events. Compared with other stages and substages in the same neighborhood, only the end-Ordovician, end-Permian, and end-Cretaceous extinction intensities appear as outliers. Moreover, when origination and extinction are considered together, only these three of the "big five" events appear to have been generated exclusively by elevated extinction. Low origination contributed more than high extinction to the marked loss of diversity in the late Frasnian and at the end of the Triassic. Therefore, whereas the "big five" events are clearly times when diversity suffered mass depletion, only those at the end of the Ordovician, Permian, and Cretaceous periods unequivocally qualify as globally distinct mass extinctions. Each of the three has a unique pattern of extinction, and the diversity dynamics of these events differ, as well, from the other two major diversity depletions. As mass depletions of diversity have no common effect, common causation seems unlikely.

@article{doi1016660094837320040300522oeamdo20co2,
    author = "Bambach, Richard K. and Knoll, Andrew H. and Wang, Steve C.",
    title = "Origination, extinction, and mass depletions of marine diversity",
    year = "2004",
    journal = "Paleobiology",
    abstract = {In post-Cambrian time, five events-the end-Ordovician, end-Frasnian in the Late Devonian, end-Permian, end-Triassic, and end-Cretaceous-are commonly grouped as the "big five" global intervals of mass extinction. Plotted by magnitude, extinction intensities for all Phanerozoic substages show a continuous distribution, with the five traditionally recognized mass extinctions located in the upper tail. Plotted by time, however, proportional extinctions clearly divide the Phanerozoic Eon into six stratigraphically coherent intervals of alternating high and low extinction intensity. These stratigraphic neighborhoods provide a temporal context for evaluating the intensity of extinction during the "big five" events. Compared with other stages and substages in the same neighborhood, only the end-Ordovician, end-Permian, and end-Cretaceous extinction intensities appear as outliers. Moreover, when origination and extinction are considered together, only these three of the "big five" events appear to have been generated exclusively by elevated extinction. Low origination contributed more than high extinction to the marked loss of diversity in the late Frasnian and at the end of the Triassic. Therefore, whereas the "big five" events are clearly times when diversity suffered mass depletion, only those at the end of the Ordovician, Permian, and Cretaceous periods unequivocally qualify as globally distinct mass extinctions. Each of the three has a unique pattern of extinction, and the diversity dynamics of these events differ, as well, from the other two major diversity depletions. As mass depletions of diversity have no common effect, common causation seems unlikely.},
    url = "https://doi.org/10.1666/0094-8373(2004)030<0522:oeamdo>2.0.co;2",
    doi = "10.1666/0094-8373(2004)030<0522:oeamdo>2.0.co;2",
    openalex = "W2128652714",
    references = "alvarez1980extraterrestrial, crossref1982geological, doi1010160169207093900885, doi101016s0012825200000374, doi101016s0012825299000550, doi101017s0094837300003778, doi101017s0094837300005248, doi101023a1011317930838, doi101038293435a0, doi101073pnas092150999, doi10108001621459197910481038, doi101111j251761611981tb01155x, doi101126science20844481095, doi101126science21545391501, doi101126science27252651155, doi101126science2825387276, doi101126science28454232129, doi1011300091761320020300251tameat20co2, doi101130spe190, doi101130spe89p63, doi1023073514678, lehman1987late, openalexw1539913220, openalexw2912219260, openalexw658437845"
}

@incollection{doi101007bfb0011152,
    author = "Harries, Peter J. and Kauffman, Erle G.",
    title = "Patterns of survival and recovery following the Cenomanian-Turonian (Late Cretaceous) mass extinction in the Western Interior Basin, United States",
    year = "2005",
    booktitle = "Lecture notes in earth sciences",
    url = "https://doi.org/10.1007/bfb0011152",
    doi = "10.1007/bfb0011152",
    openalex = "W1632286192",
    references = "alvarez1980extraterrestrial, crossref1982geological, doi1010079781489904027, doi1010160012821x85900196, doi1010160377839888900059, doi101017s0094837300007776, doi101126science23547931156, doi101130spe190p291, doi107203sjp25159, openalexw2237187854, openalexw2912219260"
}

Abstract Large impacts are credited with the most devastating mass extinctions in Earth's history and the Cretaceous – Tertiary (K/T) boundary impact is the strongest and sole direct support for this view. A review of the five largest Phanerozoic mass extinctions provides no support that impacts with craters up to 180 km in diameter caused significant species extinctions. This includes the 170 km-diameter Chicxulub impact crater regarded as 0.3 million years older than the K/T mass extinction. A second, larger impact event may have been the ultimate cause of this mass extinction, as suggested by a global iridium anomaly at the K/T boundary, but no crater has been found to date. The current crater database suggests that multiple impacts, for example comet showers, were the norm, rather than the exception, during the Late Eocene, K/T transition, latest Triassic and the Devonian – Carboniferous transition, but did not cause significant species extinctions. Whether multiple impacts substantially contributed to greenhouse warming and associated environmental stresses is yet to be demonstrated. From the current database, it must be concluded that no known Phanerozoic impacts, including the Chicxulub impact (but excluding the K/T impact) caused mass extinctions or even significant species extinctions. The K/T mass extinction may have been caused by the coincidence of a very large impact (> 250 km) upon a highly stressed biotic environment as a result of volcanism. The consistent association of large magmatic provinces (large igneous provinces and continental flood-basalt provinces) with all but one (end-Ordovician) of the five major Phanerozoic mass extinctions suggests that volcanism played a major role. Faunal and geochemical evidence from the end-Permian, end-Devonian, end-Cretaceous and Triassic/Jurassic transition suggests that the biotic stress was due to a lethal combination of tectonically induced hydrothermal and volcanic processes, leading to eutrophication in the oceans, global warming, sea-level transgression and ocean anoxia. It must be concluded that major magmatic events and their long-term environmental consequences are major contributors, though not the sole causes of mass extinctions. Sudden mass extinctions, such as at the K/T boundary, may require the coincidence of major volcanism and a very large Impact. Keywords: impactmass extinctionPhanerozoicvolcanism Acknowledgements I am grateful to all those who have contributed to this review in discussions and with generous advice and suggestions, in particular Thierry Adatte, Andrew Glikson, Norman MacLeod, Kath Grey, Andrew Hill, Alan Smith, Robert Bostrom and Leonard Johnson, all of whom have contributed in so many ways. A very special thank you to the reviewers Greg Racki, Paul Wignall and Richard Stothers who have been so generous in sharing their expertise and knowledge and thereby helped improve this paper. This study was supported by NSF Grant EAR-0207407.

@article{doi10108008120090500170393,
    author = "Keller, Gerta",
    title = "Impacts, volcanism and mass extinction: random coincidence or cause and effect?",
    year = "2005",
    journal = "Australian Journal of Earth Sciences",
    abstract = "Abstract Large impacts are credited with the most devastating mass extinctions in Earth's history and the Cretaceous – Tertiary (K/T) boundary impact is the strongest and sole direct support for this view. A review of the five largest Phanerozoic mass extinctions provides no support that impacts with craters up to 180 km in diameter caused significant species extinctions. This includes the 170 km-diameter Chicxulub impact crater regarded as 0.3 million years older than the K/T mass extinction. A second, larger impact event may have been the ultimate cause of this mass extinction, as suggested by a global iridium anomaly at the K/T boundary, but no crater has been found to date. The current crater database suggests that multiple impacts, for example comet showers, were the norm, rather than the exception, during the Late Eocene, K/T transition, latest Triassic and the Devonian – Carboniferous transition, but did not cause significant species extinctions. Whether multiple impacts substantially contributed to greenhouse warming and associated environmental stresses is yet to be demonstrated. From the current database, it must be concluded that no known Phanerozoic impacts, including the Chicxulub impact (but excluding the K/T impact) caused mass extinctions or even significant species extinctions. The K/T mass extinction may have been caused by the coincidence of a very large impact (> 250 km) upon a highly stressed biotic environment as a result of volcanism. The consistent association of large magmatic provinces (large igneous provinces and continental flood-basalt provinces) with all but one (end-Ordovician) of the five major Phanerozoic mass extinctions suggests that volcanism played a major role. Faunal and geochemical evidence from the end-Permian, end-Devonian, end-Cretaceous and Triassic/Jurassic transition suggests that the biotic stress was due to a lethal combination of tectonically induced hydrothermal and volcanic processes, leading to eutrophication in the oceans, global warming, sea-level transgression and ocean anoxia. It must be concluded that major magmatic events and their long-term environmental consequences are major contributors, though not the sole causes of mass extinctions. Sudden mass extinctions, such as at the K/T boundary, may require the coincidence of major volcanism and a very large Impact. Keywords: impactmass extinctionPhanerozoicvolcanism Acknowledgements I am grateful to all those who have contributed to this review in discussions and with generous advice and suggestions, in particular Thierry Adatte, Andrew Glikson, Norman MacLeod, Kath Grey, Andrew Hill, Alan Smith, Robert Bostrom and Leonard Johnson, all of whom have contributed in so many ways. A very special thank you to the reviewers Greg Racki, Paul Wignall and Richard Stothers who have been so generous in sharing their expertise and knowledge and thereby helped improve this paper. This study was supported by NSF Grant EAR-0207407.",
    url = "https://doi.org/10.1080/08120090500170393",
    doi = "10.1080/08120090500170393",
    openalex = "W2017489371",
    references = "alvarez1980extraterrestrial, crocket1988distribution, doi10100797836427859317, doi1010160012821x9190113v, doi1010160031018293901367, doi101016s0012825200000374, doi101016s0031018201003972, doi101016s1631071303000063, doi1010291998rg000054, doi10102993rg02508, doi101093oso97801985491780010001, doi101126science27252651155, doi101126science28153811342, doi1011300091761319910190867ccapct23co2, openalexw2751580477"
}

Abstract Calcareous nannoplankton underwent devastating diversity loss at the Cretaceous- Tertiary boundary (65.5 Ma), but recovered rapidly in the early Paleocene from a small number of survivor species. An understanding of this survivorship has been hampered by uncertainties introduced by reworking and mixing, but new high-resolution assemblage data from the northwest Pacific (Shatsky Rise, Ocean Drilling Program Site 1210) allow the unequivocal identification of 10 survivors. Evidence of shared adaptive strategies among these species provides the first indication that the extinctions were selective, with survival limited to a few neritic and/or opportunistic species, probably facilitated by hardiness and/or life-cycle escape strategies.

@article{doi101130g21566ar1,
    author = "Bown, Paul R.",
    title = "Selective calcareous nannoplankton survivorship at the Cretaceous-Tertiary boundary",
    year = "2005",
    journal = "Geology",
    abstract = "Abstract Calcareous nannoplankton underwent devastating diversity loss at the Cretaceous- Tertiary boundary (65.5 Ma), but recovered rapidly in the early Paleocene from a small number of survivor species. An understanding of this survivorship has been hampered by uncertainties introduced by reworking and mixing, but new high-resolution assemblage data from the northwest Pacific (Shatsky Rise, Ocean Drilling Program Site 1210) allow the unequivocal identification of 10 survivors. Evidence of shared adaptive strategies among these species provides the first indication that the extinctions were selective, with survival limited to a few neritic and/or opportunistic species, probably facilitated by hardiness and/or life-cycle escape strategies.",
    url = "https://doi.org/10.1130/g21566ar.1",
    doi = "10.1130/g21566ar.1",
    openalex = "W2087078687",
    references = "doi101016s0031018201003972"
}

Abstract Mass extinctions are important to macroevolution not only because they involve a sharp increase in extinction intensity over “background” levels, but also because they bring a change in extinction selectivity, and these quantitative and qualitative shifts set the stage for evolutionary recoveries. The set of extinction intensities for all stratigraphic stages appears to fall into a single right-skewed distribution, but this apparent continuity may derive from failure to factor out the well-known secular trend in background extinction: high early Paleozoic rates fill in the gap between later background extinction and the major mass extinctions. In any case, the failure of many organism-, species-, and clade-level traits to predict survivorship during mass extinctions is a more important challenge to the extrapolationist premise that all macroevolutionary processes are simply smooth extensions of microevolution. Although a variety of factors have been found to correlate with taxon survivorship for particular extinction events, the most pervasive effect involves geographic range at the clade level, an emergent property independent of the range sizes of constituent species. Such differential extinction would impose “nonconstructive selectivity,” in which survivorship is unrelated to many organismic traits but is not strictly random. It also implies that correlations among taxon attributes may obscure causation, and even the focal level of selection, in the survival of a trait or clade, for example when widespread taxa within a major group tend to have particular body sizes, trophic habits, or metabolic rates. Survivorship patterns will also be sensitive to the inexact correlations of taxonomic, morphological, and functional diversity, to phylogenetically nonrandom extinction, and to the topology of evolutionary trees. Evolutionary recoveries may be as important as the extinction events themselves in shaping the long-term trajectories of individual clades and permitting once-marginal groups to diversify, but we know little about sorting processes during recovery intervals. However, both empirical extrapolationism (where outcomes can be predicted from observation of pre- or post-extinction patterns) and theoretical extrapolationism (where mechanisms reside exclusively at the level of organisms within populations) evidently fail during mass extinctions and their evolutionary aftermath. This does not mean that conventional natural selection was inoperative during mass extinctions, but that many features that promoted survivorship during background times were superseded as predictive factors by higher-level attributes. Many intriguing issues remain, including the generality of survivorship rules across extinction events; the potential for gradational changes in selectivity patterns with extinction intensity or the volatility of target clades; the heritability of clade-level traits; the macroevolutionary consequences of the inexact correlations between taxonomic, morphological, and functional diversity; the factors governing the dynamics and outcome of recoveries; and the spatial fabric of extinctions and recoveries. The detection of general survivorship rules—including the disappearance of many patterns evident during background times—demonstrates that studies of mass extinctions and recovery can contribute substantially to evolutionary theory.

@article{doi1016660094837320050310192meam20co2,
    author = "Jablonski, David",
    title = "Mass extinctions and macroevolution",
    year = "2005",
    journal = "Paleobiology",
    abstract = "Abstract Mass extinctions are important to macroevolution not only because they involve a sharp increase in extinction intensity over “background” levels, but also because they bring a change in extinction selectivity, and these quantitative and qualitative shifts set the stage for evolutionary recoveries. The set of extinction intensities for all stratigraphic stages appears to fall into a single right-skewed distribution, but this apparent continuity may derive from failure to factor out the well-known secular trend in background extinction: high early Paleozoic rates fill in the gap between later background extinction and the major mass extinctions. In any case, the failure of many organism-, species-, and clade-level traits to predict survivorship during mass extinctions is a more important challenge to the extrapolationist premise that all macroevolutionary processes are simply smooth extensions of microevolution. Although a variety of factors have been found to correlate with taxon survivorship for particular extinction events, the most pervasive effect involves geographic range at the clade level, an emergent property independent of the range sizes of constituent species. Such differential extinction would impose “nonconstructive selectivity,” in which survivorship is unrelated to many organismic traits but is not strictly random. It also implies that correlations among taxon attributes may obscure causation, and even the focal level of selection, in the survival of a trait or clade, for example when widespread taxa within a major group tend to have particular body sizes, trophic habits, or metabolic rates. Survivorship patterns will also be sensitive to the inexact correlations of taxonomic, morphological, and functional diversity, to phylogenetically nonrandom extinction, and to the topology of evolutionary trees. Evolutionary recoveries may be as important as the extinction events themselves in shaping the long-term trajectories of individual clades and permitting once-marginal groups to diversify, but we know little about sorting processes during recovery intervals. However, both empirical extrapolationism (where outcomes can be predicted from observation of pre- or post-extinction patterns) and theoretical extrapolationism (where mechanisms reside exclusively at the level of organisms within populations) evidently fail during mass extinctions and their evolutionary aftermath. This does not mean that conventional natural selection was inoperative during mass extinctions, but that many features that promoted survivorship during background times were superseded as predictive factors by higher-level attributes. Many intriguing issues remain, including the generality of survivorship rules across extinction events; the potential for gradational changes in selectivity patterns with extinction intensity or the volatility of target clades; the heritability of clade-level traits; the macroevolutionary consequences of the inexact correlations between taxonomic, morphological, and functional diversity; the factors governing the dynamics and outcome of recoveries; and the spatial fabric of extinctions and recoveries. The detection of general survivorship rules—including the disappearance of many patterns evident during background times—demonstrates that studies of mass extinctions and recovery can contribute substantially to evolutionary theory.",
    url = "https://doi.org/10.1666/0094-8373(2005)031[0192:meam]2.0.co;2",
    doi = "10.1666/0094-8373(2005)031[0192:meam]2.0.co;2",
    openalex = "W2178500685",
    references = "doi1010029780470999592, doi1010160031018281900924, doi101016s0012825202001046, doi101016s0031018299000887, doi101017s0094837300008186, doi101017s0094837300011350, doi101017s0094837300011787, doi101017s0094837300013178, doi101017s0094837300015864, doi101093oso97801985264070010001, doi101093plankt212343, doi101111j150239311986tb01898x, doi101126science1103960, doi101126science11536722, doi101126science21545391501, doi101126science2825387276, doi101144gsjgs15420265, doi101146annurevecolsys281495, doi101146annurevecolsys33030602152151, doi101666009483731999251mditer20co2, doi1016660094837320000260056cefisg20co2, doi1016660094837320050310006poaeit20co2, doi1023072409086, doi1023073514632, doi1023073515466, doi105860choice396411, hotton2002palynology, kitchell1986biological, openalexw2145250129, openalexw2764433274, rickards2002lazarus"
}

Mass extinctions can play a role in shaping macroevolutionary trends through time, but the contribution of recoveries to this process has yet to be examined in detail. This study focuses on the effects of three extinction events, the end-Cretaceous (K/T), mid-Eocene (mid-E), and end-Eocene (E/O), on long-term patterns of body size in veneroid bivalves. Systematic data were collected for 719 species and 140 subgenera of veneroids from the Late Cretaceous through Oligocene of North America and Europe. Centroid size measures were calculated for 101 subgenera and global stratigraphic ranges were used to assess extinction selectivity and preferential recovery. Veneroids underwent a substantial extinction at the K/T boundary, although diversity recovered to pre-extinction levels by the early Eocene. The mid-E and E/O events were considerably smaller and their recovery intervals much shorter. None of these events were characterized by significant extinction selectivity according to body size at the subgenus level; however, all three recoveries were strongly size biased. The K/T recovery was biased toward smaller veneroids, whereas both the mid-E and E/O recoveries were biased toward larger ones. The decrease in veneroid size across the K/T recovery actually reinforced a Late Cretaceous trend toward smaller sizes, whereas the increase in size resulting from the Eocene recoveries was relatively short-lived. Early Cenozoic changes in predation, temperature, and/or productivity may explain these shifts.

@article{doi1016660094837320050310578bseeat20co2,
    author = "Lockwood, Rowan",
    title = "Body size, extinction events, and the early Cenozoic record of veneroid bivalves: a new role for recoveries?",
    year = "2005",
    journal = "Paleobiology",
    abstract = "Mass extinctions can play a role in shaping macroevolutionary trends through time, but the contribution of recoveries to this process has yet to be examined in detail. This study focuses on the effects of three extinction events, the end-Cretaceous (K/T), mid-Eocene (mid-E), and end-Eocene (E/O), on long-term patterns of body size in veneroid bivalves. Systematic data were collected for 719 species and 140 subgenera of veneroids from the Late Cretaceous through Oligocene of North America and Europe. Centroid size measures were calculated for 101 subgenera and global stratigraphic ranges were used to assess extinction selectivity and preferential recovery. Veneroids underwent a substantial extinction at the K/T boundary, although diversity recovered to pre-extinction levels by the early Eocene. The mid-E and E/O events were considerably smaller and their recovery intervals much shorter. None of these events were characterized by significant extinction selectivity according to body size at the subgenus level; however, all three recoveries were strongly size biased. The K/T recovery was biased toward smaller veneroids, whereas both the mid-E and E/O recoveries were biased toward larger ones. The decrease in veneroid size across the K/T recovery actually reinforced a Late Cretaceous trend toward smaller sizes, whereas the increase in size resulting from the Eocene recoveries was relatively short-lived. Early Cenozoic changes in predation, temperature, and/or productivity may explain these shifts.",
    url = "https://doi.org/10.1666/0094-8373(2005)031[0578:bseeat]2.0.co;2",
    doi = "10.1666/0094-8373(2005)031[0578:bseeat]2.0.co;2",
    openalex = "W2134145562",
    references = "doi101016s0031018299000887, doi101017s0094837300011787"
}

Various fractions of the soluble organic compounds were isolated from iridium rich sediments using combination of extraction techniques and different proportions of benzene, chloroform and methanol with petroleum ether. Analysis of these compounds showed the presence of α, β unsaturated ester (C=C-COO-) and aliphatic long chain alkyl groups (-C-C-C-C-) in the iridium enriched Cretaceous-Tertiary (K-T) boundary sediments. The two proton peaks of δ 7.20 and 7.26 ppm of the 1H NMR spectra, indicate that the molecule may be of glyceride with aliphatic long chain alkyl groups. Similarly, peaks in the region of δ 3.90-4.32 ppm show the presence of a double bond (-C=C-) structure attached to an ester group. Peaks found in the region of 7.5-7.7 ppm showed the presence of aromatic hydrocarbons. The peaks at δ 128 and 130 ppm in the 13C NMR spectrum also support the presence of a double bond (-C=C-) structure attached to an ester group. Two peaks at δ 68 and 70 ppm are assigned to two alkyl groups attached to an ester group (-CH2-CH2-OOC-). The spectrum of clay-intercalated geopolymer of the Ir enriched layer is comparable to lignin having chemical shifts of aromatic C (160 to 110 ppm), O alkyl C (100 to 60 ppm) and (45 to 0 ppm) alkyl C structures. The solidstate 13C NMR spectrum of lignin reveals a pattern comparable to those obtained in other studies of angiosperm woods. These simple predominantly long chain aliphatic organic compounds are derivatives of complex organic molecules, formed by sudden increase in temperature, but at low-pressure conditions. It is possible that hydrothermal fluids associated with Deccan volcanism supplied heat at the time of these transformations. These observations draw support from the presence of sepiolite-palygorskite-smectite complexes in the Anjar volcano-sedimentary sequences, indicating high basicity under arid conditions induced and influenced by the Deccan volcanism.

@article{openalexw106214291,
    author = "Shrivastava, J. P. and Ahmad, Mansoor",
    title = "Compositional studies on organic matter from Iridiium enriched Anjar intertrappean sediments: Deccan volcanism and palaeoenvironmental implications during the Cretaceous/Tertiary boundary",
    year = "2005",
    journal = "Journal of iberian geology: an international publication of earth sciences",
    abstract = "Various fractions of the soluble organic compounds were isolated from iridium rich sediments using combination of extraction techniques and different proportions of benzene, chloroform and methanol with petroleum ether. Analysis of these compounds showed the presence of α, β unsaturated ester (C=C-COO-) and aliphatic long chain alkyl groups (-C-C-C-C-) in the iridium enriched Cretaceous-Tertiary (K-T) boundary sediments. The two proton peaks of δ 7.20 and 7.26 ppm of the 1H NMR spectra, indicate that the molecule may be of glyceride with aliphatic long chain alkyl groups. Similarly, peaks in the region of δ 3.90-4.32 ppm show the presence of a double bond (-C=C-) structure attached to an ester group. Peaks found in the region of 7.5-7.7 ppm showed the presence of aromatic hydrocarbons. The peaks at δ 128 and 130 ppm in the 13C NMR spectrum also support the presence of a double bond (-C=C-) structure attached to an ester group. Two peaks at δ 68 and 70 ppm are assigned to two alkyl groups attached to an ester group (-CH2-CH2-OOC-). The spectrum of clay-intercalated geopolymer of the Ir enriched layer is comparable to lignin having chemical shifts of aromatic C (160 to 110 ppm), O alkyl C (100 to 60 ppm) and (45 to 0 ppm) alkyl C structures. The solidstate 13C NMR spectrum of lignin reveals a pattern comparable to those obtained in other studies of angiosperm woods. These simple predominantly long chain aliphatic organic compounds are derivatives of complex organic molecules, formed by sudden increase in temperature, but at low-pressure conditions. It is possible that hydrothermal fluids associated with Deccan volcanism supplied heat at the time of these transformations. These observations draw support from the presence of sepiolite-palygorskite-smectite complexes in the Anjar volcano-sedimentary sequences, indicating high basicity under arid conditions induced and influenced by the Deccan volcanism.",
    openalex = "W106214291",
    references = "doi101016s0168632106800271"
}

Recent analyses of Sepkoski's genus-level compendium show that only three events form a statistically separate class of high extinction intensities when only post-Early Ordovician intervals are considered, but geologists have called numerous events mass extinctions. Is this a conflict? A review of different methods of tabulating data from the Sepkoski database reveals 18 intervals during the Phanerozoic have peaks of both magnitude and rate of extinction that appear in each tabulating scheme. These intervals all fit Sepkoski's definition of mass extinction. However, they vary widely in timing and effect of extinction, demonstrating that mass extinctions are not a homogeneous group of events. No consensus has been reached on the kill mechanism for any marine mass extinction. In fact, adequate data on timing in ecologic, rather than geologic, time and on geographic and environmental distribution of extinction have not yet been systematically compiled for any extinction event.

@article{doi101146annurevearth33092203122654,
    author = "Bambach, Richard K.",
    title = "PHANEROZOIC BIODIVERSITY MASS EXTINCTIONS",
    year = "2006",
    journal = "Annual Review of Earth and Planetary Sciences",
    abstract = "Recent analyses of Sepkoski's genus-level compendium show that only three events form a statistically separate class of high extinction intensities when only post-Early Ordovician intervals are considered, but geologists have called numerous events mass extinctions. Is this a conflict? A review of different methods of tabulating data from the Sepkoski database reveals 18 intervals during the Phanerozoic have peaks of both magnitude and rate of extinction that appear in each tabulating scheme. These intervals all fit Sepkoski's definition of mass extinction. However, they vary widely in timing and effect of extinction, demonstrating that mass extinctions are not a homogeneous group of events. No consensus has been reached on the kill mechanism for any marine mass extinction. In fact, adequate data on timing in ecologic, rather than geologic, time and on geographic and environmental distribution of extinction have not yet been systematically compiled for any extinction event.",
    url = "https://doi.org/10.1146/annurev.earth.33.092203.122654",
    doi = "10.1146/annurev.earth.33.092203.122654",
    openalex = "W2107407744",
    references = "alvarez1980extraterrestrial, doi101007978364270831215, doi101016003101829400093n, doi101016s001282520000026x, doi101016s0012825200000374, doi101016s0012825203000825, doi101016s0012825299000550, doi101016s0031018299000863, doi101016s0169534703000934, doi101017cbo9780511536045, doi101017s0094837300004929, doi101017s0094837300005649, doi101073pnas092150999, doi101073pnas813801, doi101093oso97801985491780010001, doi101126science1097023, doi101126science1101476, doi101126science21545391501, doi101126science27252651155, doi101130spe89p63, doi1016660094837320040300522oeamdo20co2, doi1016660094837320050310006poaeit20co2, doi1023073515270, doi104095215638, openalexw2989049194"
}

Stevns Klint is a 14.5 km long coastal cliff south of Copenhagen, Denmark. It is a classical Cretaceous–Tertiary boundary locality and constitutes the type locality of the Danian Stage together with the nearby Faxe quarry. The irregular coastal topography, the presence of numerous old quarries in the upper, Danian part of the cliff section, and the inaccessibility of parts of the coast makes it difficult to construct an exact geological profile of the whole length of the cliff. Until now the only profile is a fine engraved pen drawing from a boat by Puggaard in 1853. We present a new profile of the cliff constructed on the basis of multi-model photogrammetric mapping of a long series of overlapping photographs taken from a small airplane. This was supplemented by photography and observations from a boat and from the beach. The exposed succession is about 45 m thick and is subdivided into a series of new lithostratigraphic units. It shows the stratigraphic evolution from the uppermost Maastrichtian, across the Cretaceous–Tertiary boundary and into the lower Danian. The position of the boundary varies from about 5 m below to about 30 m above present day sea level. The irregular relief has been interpreted as due to Paleogene folding but it actually represents a depositional sea-floor topography. The lower part of the succession comprises about 25 m of upper Maastrichtian benthos-rich chalk of the newSigerslev Member showing irregular low-amplitude mounded bedding outlined by thin layers of nodular flint, passing upward into benthos-poor, gently wavy to almost horizontally bedded chalk poor in flint. The member is capped by a double incipient hardground and a prominent marker band of nodular flint, occurring 30–50 cm beneath the upper hardground can be followed along the length of the cliff. The upper hardground is overlain by uppermost Maastrichtian bryozoan chalk wackestone deposited in low asymmetrical mounds of the new Højerup Member. It is 4–5 m thick in the southern part of the cliff, thins gradually to the north, and has wedged out almost completely at the northern end of the cliff. The new Sigerslev and Højerup Members form the top part of the Maastrichtian Tor Formation in the Stevns Klint area. It is overlain by the new lowermost Danian Fiskeler Member (P0 foraminifer Zone) which drapes the troughs between the mound crests and wedges out gradually towards the margins of the troughs. It is generally about 5–10 cm thick and passes gradually upwards into the strongly burrowed new Cerithium Limestone Member (Pα–P1a Zones), which is up to 60 cm thick. The Fiskeler and Cerithium Limestone Members form the new Rødvig Formation. An erosional hardground surface truncates the top of the Cerithium Limestone Member and the intervening crests of the uppermost Maastrichtian mounds of the Højerup Member. The surface is overlain by lower Danian bryozoan packstone–rudstone mound complexes (foraminifer zones P1b–P1c, local coccolith zones 2–3, Nannoplankton Zones D2–D3). The internal architecture of the mounds is outlined by thick black flint layers and the mounded bryozoan limestone belongs to the new Korsnæb Member of the new Stevns Klint Formation. Up to 20 m of bryozoan limestone are preserved beneath the Quaternary deposits, forming the top of the cliff succession. The new photogrammetric profile may serve as an excursion guide, as a basis for detailed sedimentological study, and for biostratigraphical, geochemical and palaeomagnetic sampling. Finally, it illustrates the geometry, dimensions and architecture of one of the finest carbonate mound complexes known.

@article{doi1037570bgsd20065401,
    author = "Surlyk, F. Damholt and Bjerager, Morten and Damholt, Tove",
    title = "Stevns Klint, Denmark: Uppermost Maastrichtian chalk, Cretaceous–Tertiary boundary, and lower Danian bryozoan mound complex",
    year = "2006",
    journal = "Bulletin of the Geological Society of Denmark",
    abstract = "Stevns Klint is a 14.5 km long coastal cliff south of Copenhagen, Denmark. It is a classical Cretaceous–Tertiary boundary locality and constitutes the type locality of the Danian Stage together with the nearby Faxe quarry. The irregular coastal topography, the presence of numerous old quarries in the upper, Danian part of the cliff section, and the inaccessibility of parts of the coast makes it difficult to construct an exact geological profile of the whole length of the cliff. Until now the only profile is a fine engraved pen drawing from a boat by Puggaard in 1853. We present a new profile of the cliff constructed on the basis of multi-model photogrammetric mapping of a long series of overlapping photographs taken from a small airplane. This was supplemented by photography and observations from a boat and from the beach. The exposed succession is about 45 m thick and is subdivided into a series of new lithostratigraphic units. It shows the stratigraphic evolution from the uppermost Maastrichtian, across the Cretaceous–Tertiary boundary and into the lower Danian. The position of the boundary varies from about 5 m below to about 30 m above present day sea level. The irregular relief has been interpreted as due to Paleogene folding but it actually represents a depositional sea-floor topography. The lower part of the succession comprises about 25 m of upper Maastrichtian benthos-rich chalk of the newSigerslev Member showing irregular low-amplitude mounded bedding outlined by thin layers of nodular flint, passing upward into benthos-poor, gently wavy to almost horizontally bedded chalk poor in flint. The member is capped by a double incipient hardground and a prominent marker band of nodular flint, occurring 30–50 cm beneath the upper hardground can be followed along the length of the cliff. The upper hardground is overlain by uppermost Maastrichtian bryozoan chalk wackestone deposited in low asymmetrical mounds of the new Højerup Member. It is 4–5 m thick in the southern part of the cliff, thins gradually to the north, and has wedged out almost completely at the northern end of the cliff. The new Sigerslev and Højerup Members form the top part of the Maastrichtian Tor Formation in the Stevns Klint area. It is overlain by the new lowermost Danian Fiskeler Member (P0 foraminifer Zone) which drapes the troughs between the mound crests and wedges out gradually towards the margins of the troughs. It is generally about 5–10 cm thick and passes gradually upwards into the strongly burrowed new Cerithium Limestone Member (Pα–P1a Zones), which is up to 60 cm thick. The Fiskeler and Cerithium Limestone Members form the new Rødvig Formation. An erosional hardground surface truncates the top of the Cerithium Limestone Member and the intervening crests of the uppermost Maastrichtian mounds of the Højerup Member. The surface is overlain by lower Danian bryozoan packstone–rudstone mound complexes (foraminifer zones P1b–P1c, local coccolith zones 2–3, Nannoplankton Zones D2–D3). The internal architecture of the mounds is outlined by thick black flint layers and the mounded bryozoan limestone belongs to the new Korsnæb Member of the new Stevns Klint Formation. Up to 20 m of bryozoan limestone are preserved beneath the Quaternary deposits, forming the top of the cliff succession. The new photogrammetric profile may serve as an excursion guide, as a basis for detailed sedimentological study, and for biostratigraphical, geochemical and palaeomagnetic sampling. Finally, it illustrates the geometry, dimensions and architecture of one of the finest carbonate mound complexes known.",
    url = "https://doi.org/10.37570/bgsd-2006-54-01",
    doi = "10.37570/bgsd-2006-54-01",
    openalex = "W3124267817",
    references = "doi101016s0031018299000887"
}

@article{doi101016jpalaeo200702009,
    author = "Aguirre, Julio and Baceta, Juan Ignacio and Braga, Juan C.",
    title = "Recovery of marine primary producers after the Cretaceous–Tertiary mass extinction: Paleocene calcareous red algae from the Iberian Peninsula",
    year = "2007",
    journal = "Palaeogeography Palaeoclimatology Palaeoecology",
    url = "https://doi.org/10.1016/j.palaeo.2007.02.009",
    doi = "10.1016/j.palaeo.2007.02.009",
    openalex = "W2086175528",
    references = "doi101007bf02536880"
}

Wide geographic range is generally thought to buffer taxa against extinction, but the strength of this effect has not been investigated for the great majority of the fossil record. Although the majority of genus extinctions have occurred between major mass extinctions, little is known about extinction selectivity regimes during these "background" intervals. Consequently, the question of whether selectivity regimes differ between background and mass extinctions is largely unresolved. Using logistic regression, we evaluated the selectivity of genus survivorship with respect to geographic range by using a global database of fossil benthic marine invertebrates spanning the Cambrian through the Neogene periods, an interval of approximately 500 My. Our results show that wide geographic range has been significantly and positively associated with survivorship for the great majority of Phanerozoic time. Moreover, the significant association between geographic range and survivorship remains after controlling for differences in species richness and abundance among genera. However, mass extinctions and several second-order extinction events exhibit less geographic range selectivity than predicted by range alone. Widespread environmental disturbance can explain the reduced association between geographic range and extinction risk by simultaneously affecting genera with similar ecological and physiological characteristics on global scales. Although factors other than geographic range have certainly affected extinction risk during many intervals, geographic range is likely the most consistently significant predictor of extinction risk in the marine fossil record.

@article{doi101073pnas0701257104,
    author = "Payne, Jonathan L. and Finnegan, Seth",
    title = "The effect of geographic range on extinction risk during background and mass extinction",
    year = "2007",
    journal = "Proceedings of the National Academy of Sciences",
    abstract = {Wide geographic range is generally thought to buffer taxa against extinction, but the strength of this effect has not been investigated for the great majority of the fossil record. Although the majority of genus extinctions have occurred between major mass extinctions, little is known about extinction selectivity regimes during these "background" intervals. Consequently, the question of whether selectivity regimes differ between background and mass extinctions is largely unresolved. Using logistic regression, we evaluated the selectivity of genus survivorship with respect to geographic range by using a global database of fossil benthic marine invertebrates spanning the Cambrian through the Neogene periods, an interval of approximately 500 My. Our results show that wide geographic range has been significantly and positively associated with survivorship for the great majority of Phanerozoic time. Moreover, the significant association between geographic range and survivorship remains after controlling for differences in species richness and abundance among genera. However, mass extinctions and several second-order extinction events exhibit less geographic range selectivity than predicted by range alone. Widespread environmental disturbance can explain the reduced association between geographic range and extinction risk by simultaneously affecting genera with similar ecological and physiological characteristics on global scales. Although factors other than geographic range have certainly affected extinction risk during many intervals, geographic range is likely the most consistently significant predictor of extinction risk in the marine fossil record.},
    url = "https://doi.org/10.1073/pnas.0701257104",
    doi = "10.1073/pnas.0701257104",
    openalex = "W2081757060",
    references = "doi1010020471722146, doi101016s0012825299000550, doi101093oso97801985491780010001, doi101098rstb19980195, doi101126science1097023, doi101126science11536722, doi101126science21545391501, doi101126science28554321386, doi101126science2895478432, doi101146annurevearth33092203122654, doi1023073515466, doi105860choice273338"
}

Geological investigations in the upper Manasquan River Basin, central Monmouth County, New Jersey, reveal a Cretaceous/Tertiary (= Cretaceous/Paleogene) succession consisting of approximately 2 m of the Tinton Formation overlain by 2 m of the Hornerstown Formation. The top of the Tinton Formation consists of a very fossiliferous unit, approximately 20 cm thick, which we refer to as the Pinna Layer. It is laterally extensive and consists mostly of glauconitic minerals and some angular quartz grains. The Pinna Layer is truncated at the top and is overlain by the Hornerstown Formation, which consists of nearly equal amounts of glauconitic minerals and siderite. The base of the Hornerstown Formation is marked by a concentration of siderite nodules containing reworked fossils. This layer also contains a few fossils of organisms that were living in the environment during the time of reworking. At some downdip sites, there is an additional layer (the Burrowed Unit), which is sandwiched between the top of the Pinna Layer and the concentrated bed of nodules. This unit is very thin and is characterized by large burrows piping down material from above.The Pinna Layer is abundantly fossiliferous and represents a diverse, nearshore marine community. It contains approximately 110 species of bivalves, gastropods, cephalopods, echinoids, sponges, annelids, bryozoans, crustaceans, and dinoflagellates. The cephalopods include Eutrephoceras dekayi (Morton, 1834), Pachydiscus (Neodesmoceras) mokotibensis Collignon, 1952, Sphenodiscus lobatus (Tuomey, 1856), Eubaculites carinatus (Morton, 1834), Eubaculites latecarinatus (Brunnschweiler, 1966), Discoscaphites iris (Conrad, 1858), Discoscaphites sphaeroidalis Kennedy and Cobban, 2000, Discoscaphites minardi Landman et al., 2004b, Discoscaphites gulosus (Morton, 1834), and Discoscaphites jerseyensis, n.sp. The dinoflagellates include Palynodinium grallator Gocht, 1970, Thalassiphora pelagica (Eisenack, 1954) Eisenack & Gocht, 1960, Deflandrea galeata (Lejeune-Carpentier, 1942) Lentin & Williams, 1973, and Disphaerogena carposphaeropsis Wetzel, 1933. These ammonites and dinoflagellates are indicative of the uppermost Maastrichtian, corresponding to the upper part of calcareous nannofossil Subzone CC26b.The mode of occurrence of the fossils in the Pinna Layer suggests an autochthonous accumulation with little or no postmortem transport. Many of the benthic organisms are preserved in life position. For example, specimens of Pinna laqueata Conrad, 1858, are oriented in a vertical position, similar to that of modern members of this genus. The echinoids also occur in aggregations of hundreds of individuals, suggesting gregarious feeding behavior. In addition, there are monospecific clusters of baculites and scaphites. These clusters are biological in origin and could not have been produced by hydraulic means. Scaphite jaws are also present, representing the first reports of these structures in the Upper Cretaceous of the Atlantic Coastal Plain. They occur both as isolated specimens and inside the body chamber, and indicate little or no postmortem transport.The Pinna Layer represents a geologically short interval of time. The fact that most of the animals are mature suggests that the community persisted for at least 5–10 years. If multiple generations of animals are present, perhaps reflecting multiple episodes of colonization and burial, then this unit probably represents more time, amounting to several tens of years. The fact that the Pinna Layer is truncated at the top implies a still longer period of time, amounting to hundreds of years. These age estimates are consistent with observed rates of sedimentation in nearshore environments.Iridium analyses of 37 samples of sediment from three sites in the Manasquan River Basin reveal an elevated concentration of iridium of 520 pg/g, on average, at the base of the Pinna Layer. The iridium profile is aymmetric with an abrupt drop off above the base of this u

@article{doi1012060003009020073031cfttbi20co2,
    author = "Landman, Neil H. and Johnson, Ralph O. and Garb, Matthew P. and Edwards, Lucy E. and Kyte, Frank T.",
    title = "CEPHALOPODS FROM THE CRETACEOUS/TERTIARY BOUNDARY INTERVAL ON THE ATLANTIC COASTAL PLAIN, WITH A DESCRIPTION OF THE HIGHEST AMMONITE ZONES IN NORTH AMERICA. PART III. MANASQUAN RIVER BASIN, MONMOUTH COUNTY, NEW JERSEY",
    year = "2007",
    journal = "Bulletin of the American Museum of Natural History",
    abstract = "Geological investigations in the upper Manasquan River Basin, central Monmouth County, New Jersey, reveal a Cretaceous/Tertiary (= Cretaceous/Paleogene) succession consisting of approximately 2 m of the Tinton Formation overlain by 2 m of the Hornerstown Formation. The top of the Tinton Formation consists of a very fossiliferous unit, approximately 20 cm thick, which we refer to as the Pinna Layer. It is laterally extensive and consists mostly of glauconitic minerals and some angular quartz grains. The Pinna Layer is truncated at the top and is overlain by the Hornerstown Formation, which consists of nearly equal amounts of glauconitic minerals and siderite. The base of the Hornerstown Formation is marked by a concentration of siderite nodules containing reworked fossils. This layer also contains a few fossils of organisms that were living in the environment during the time of reworking. At some downdip sites, there is an additional layer (the Burrowed Unit), which is sandwiched between the top of the Pinna Layer and the concentrated bed of nodules. This unit is very thin and is characterized by large burrows piping down material from above.The Pinna Layer is abundantly fossiliferous and represents a diverse, nearshore marine community. It contains approximately 110 species of bivalves, gastropods, cephalopods, echinoids, sponges, annelids, bryozoans, crustaceans, and dinoflagellates. The cephalopods include Eutrephoceras dekayi (Morton, 1834), Pachydiscus (Neodesmoceras) mokotibensis Collignon, 1952, Sphenodiscus lobatus (Tuomey, 1856), Eubaculites carinatus (Morton, 1834), Eubaculites latecarinatus (Brunnschweiler, 1966), Discoscaphites iris (Conrad, 1858), Discoscaphites sphaeroidalis Kennedy and Cobban, 2000, Discoscaphites minardi Landman et al., 2004b, Discoscaphites gulosus (Morton, 1834), and Discoscaphites jerseyensis, n.sp. The dinoflagellates include Palynodinium grallator Gocht, 1970, Thalassiphora pelagica (Eisenack, 1954) Eisenack \& Gocht, 1960, Deflandrea galeata (Lejeune-Carpentier, 1942) Lentin \& Williams, 1973, and Disphaerogena carposphaeropsis Wetzel, 1933. These ammonites and dinoflagellates are indicative of the uppermost Maastrichtian, corresponding to the upper part of calcareous nannofossil Subzone CC26b.The mode of occurrence of the fossils in the Pinna Layer suggests an autochthonous accumulation with little or no postmortem transport. Many of the benthic organisms are preserved in life position. For example, specimens of Pinna laqueata Conrad, 1858, are oriented in a vertical position, similar to that of modern members of this genus. The echinoids also occur in aggregations of hundreds of individuals, suggesting gregarious feeding behavior. In addition, there are monospecific clusters of baculites and scaphites. These clusters are biological in origin and could not have been produced by hydraulic means. Scaphite jaws are also present, representing the first reports of these structures in the Upper Cretaceous of the Atlantic Coastal Plain. They occur both as isolated specimens and inside the body chamber, and indicate little or no postmortem transport.The Pinna Layer represents a geologically short interval of time. The fact that most of the animals are mature suggests that the community persisted for at least 5–10 years. If multiple generations of animals are present, perhaps reflecting multiple episodes of colonization and burial, then this unit probably represents more time, amounting to several tens of years. The fact that the Pinna Layer is truncated at the top implies a still longer period of time, amounting to hundreds of years. These age estimates are consistent with observed rates of sedimentation in nearshore environments.Iridium analyses of 37 samples of sediment from three sites in the Manasquan River Basin reveal an elevated concentration of iridium of 520 pg/g, on average, at the base of the Pinna Layer. The iridium profile is aymmetric with an abrupt drop off above the base of this u",
    url = "https://doi.org/10.1206/0003-0090(2007)303[1:cfttbi]2.0.co;2",
    doi = "10.1206/0003-0090(2007)303[1:cfttbi]2.0.co;2",
    openalex = "W2122840541",
    references = "doi101002qj49707532417, doi101016s0031018299000887, doi101017s0016756800083710, doi101017s0022336000024331, doi101017s0022336000061096, doi101038017199b0, doi101038114085a0, doi101038141548c0, doi101086273307, doi101093nqs5vi146318i, doi101093oso97801985491780010001, doi1011300091761320010291055mctbsi20co2, doi102110pec95040129, doi103133pp151, doi103133pp331b, ganapathy1981iridium, openalexw2751580477, openalexw52563376, openalexw657396478, sohl1960archeogastropoda"
}

The fossil record amply shows that the spatial fabric of extinction has profoundly shaped the biosphere; this spatial dimension provides a powerful context for integration of paleontological and neontological approaches. Mass extinctions evidently alter extinction selectivity, with many factors losing effectiveness except for a positive relation between survivorship and geographic range at the clade level (confirmed in reanalyses of end-Cretaceous extinction data). This relation probably also holds during "normal" times, but changes both slope and intercept with increasing extinction. The strong geographical component to clade dynamics can obscure causation in the extinction of a feature or a clade, owing to hitchhiking effects on geographic range, so that multifactorial analyses are needed. Some extinctions are spatially complex, and regional extinctions might either reset a diversity ceiling or create a diversification debt open to further diversification or invasion. Evolutionary recoveries also exhibit spatial dynamics, including regional differences in invasibilty, and expansion of clades from the tropics fuels at least some recoveries, as well as biodiversity dynamics during normal times. Incumbency effects apparently correlate more closely with extinction intensities than with standing diversities, so that regions with higher local and global extinctions are more subject to invasion; the latest Cenozoic temperate zones evidently received more invaders than the tropics or poles, but this dynamic could shift dramatically if tropical diversity is strongly depleted. The fossil record can provide valuable insights, and their application to present-day issues will be enhanced by partitioning past and present-day extinctions by driving mechanism rather than emphasizing intensity.

@article{doi101073pnas0801919105,
    author = "Jablonski, David",
    title = "Extinction and the spatial dynamics of biodiversity",
    year = "2008",
    journal = "Proceedings of the National Academy of Sciences",
    abstract = {The fossil record amply shows that the spatial fabric of extinction has profoundly shaped the biosphere; this spatial dimension provides a powerful context for integration of paleontological and neontological approaches. Mass extinctions evidently alter extinction selectivity, with many factors losing effectiveness except for a positive relation between survivorship and geographic range at the clade level (confirmed in reanalyses of end-Cretaceous extinction data). This relation probably also holds during "normal" times, but changes both slope and intercept with increasing extinction. The strong geographical component to clade dynamics can obscure causation in the extinction of a feature or a clade, owing to hitchhiking effects on geographic range, so that multifactorial analyses are needed. Some extinctions are spatially complex, and regional extinctions might either reset a diversity ceiling or create a diversification debt open to further diversification or invasion. Evolutionary recoveries also exhibit spatial dynamics, including regional differences in invasibilty, and expansion of clades from the tropics fuels at least some recoveries, as well as biodiversity dynamics during normal times. Incumbency effects apparently correlate more closely with extinction intensities than with standing diversities, so that regions with higher local and global extinctions are more subject to invasion; the latest Cenozoic temperate zones evidently received more invaders than the tropics or poles, but this dynamic could shift dramatically if tropical diversity is strongly depleted. The fossil record can provide valuable insights, and their application to present-day issues will be enhanced by partitioning past and present-day extinctions by driving mechanism rather than emphasizing intensity.},
    url = "https://doi.org/10.1073/pnas.0801919105",
    doi = "10.1073/pnas.0801919105",
    openalex = "W2016366567",
    references = "doi101016jpalaeo200602003, doi101017s0094837300011787, doi101111j150239311986tb01898x, doi101126science11537491, smith2007marine"
}

Many scientists argue that we are either entering or in the midst of the sixth great mass extinction. Intense human pressure, both direct and indirect, is having profound effects on natural environments. The amphibians--frogs, salamanders, and caecilians--may be the only major group currently at risk globally. A detailed worldwide assessment and subsequent updates show that one-third or more of the 6,300 species are threatened with extinction. This trend is likely to accelerate because most amphibians occur in the tropics and have small geographic ranges that make them susceptible to extinction. The increasing pressure from habitat destruction and climate change is likely to have major impacts on narrowly adapted and distributed species. We show that salamanders on tropical mountains are particularly at risk. A new and significant threat to amphibians is a virulent, emerging infectious disease, chytridiomycosis, which appears to be globally distributed, and its effects may be exacerbated by global warming. This disease, which is caused by a fungal pathogen and implicated in serious declines and extinctions of >200 species of amphibians, poses the greatest threat to biodiversity of any known disease. Our data for frogs in the Sierra Nevada of California show that the fungus is having a devastating impact on native species, already weakened by the effects of pollution and introduced predators. A general message from amphibians is that we may have little time to stave off a potential mass extinction.

@article{doi101073pnas0801921105,
    author = "Wake, David B. and Vredenburg, Vance T.",
    title = "Are we in the midst of the sixth mass extinction? A view from the world of amphibians",
    year = "2008",
    journal = "Proceedings of the National Academy of Sciences",
    abstract = "Many scientists argue that we are either entering or in the midst of the sixth great mass extinction. Intense human pressure, both direct and indirect, is having profound effects on natural environments. The amphibians--frogs, salamanders, and caecilians--may be the only major group currently at risk globally. A detailed worldwide assessment and subsequent updates show that one-third or more of the 6,300 species are threatened with extinction. This trend is likely to accelerate because most amphibians occur in the tropics and have small geographic ranges that make them susceptible to extinction. The increasing pressure from habitat destruction and climate change is likely to have major impacts on narrowly adapted and distributed species. We show that salamanders on tropical mountains are particularly at risk. A new and significant threat to amphibians is a virulent, emerging infectious disease, chytridiomycosis, which appears to be globally distributed, and its effects may be exacerbated by global warming. This disease, which is caused by a fungal pathogen and implicated in serious declines and extinctions of >200 species of amphibians, poses the greatest threat to biodiversity of any known disease. Our data for frogs in the Sierra Nevada of California show that the fungus is having a devastating impact on native species, already weakened by the effects of pollution and introduced predators. A general message from amphibians is that we may have little time to stave off a potential mass extinction.",
    url = "https://doi.org/10.1073/pnas.0801921105",
    doi = "10.1073/pnas.0801921105",
    openalex = "W2049085830",
    references = "doi101038nature04246, doi101046j14724642200300016x, doi10108010635150701397635, doi101126science1103538"
}

A quantitative scale for measuring greatness, G, of mass extinctions is proposed on the basis of rate of biodiversity diminution expressed as the product of the loss of biodiversity, called magnitude (M), and the inverse of time in which that loss occurs, designated as intensity (I). On this scale, the catastrophic Cretaceous-Tertiary (K-T) extinction appears as the greatest since the Ordovician and the only one with a probable extraterrestrial cause. The end-Permian extinction was less great but with a large magnitude (M) and smaller intensity (I); only some of its individual episodes involved some semblance of catastrophe. Other extinctions during the Phanerozoic, with the possible exception of the end-Silurian diversity plunge, were parts of a forced oscillatory phenomenon and seem caused by marine- and land-habitat destruction during continental assemblies that led to elimination of shelves and (after the Devonian) rain forests and enlargement of deserts. Glaciations and orogenies that shortened and thickened the continental crust only exacerbated these effects. During the Mesozoic and Cainozoic, the evolution of life was linearly progressive, interrupted catastrophically only at the K-T boundary. The end-Triassic extinction was more like the Paleozoic extinctions in nature and probably also in its cause. By contrast, the current extinction resembles none of the earlier ones and may end up being the greatest of all.

@article{doi101073pnas0805482105,
    author = "Sengör, A M Celâl and Atayman, Saniye and Ozeren, Sinan",
    title = "A scale of greatness and causal classification of mass extinctions: implications for mechanisms.",
    year = "2008",
    journal = "Proceedings of the National Academy of Sciences of the United States of America",
    abstract = "A quantitative scale for measuring greatness, G, of mass extinctions is proposed on the basis of rate of biodiversity diminution expressed as the product of the loss of biodiversity, called magnitude (M), and the inverse of time in which that loss occurs, designated as intensity (I). On this scale, the catastrophic Cretaceous-Tertiary (K-T) extinction appears as the greatest since the Ordovician and the only one with a probable extraterrestrial cause. The end-Permian extinction was less great but with a large magnitude (M) and smaller intensity (I); only some of its individual episodes involved some semblance of catastrophe. Other extinctions during the Phanerozoic, with the possible exception of the end-Silurian diversity plunge, were parts of a forced oscillatory phenomenon and seem caused by marine- and land-habitat destruction during continental assemblies that led to elimination of shelves and (after the Devonian) rain forests and enlargement of deserts. Glaciations and orogenies that shortened and thickened the continental crust only exacerbated these effects. During the Mesozoic and Cainozoic, the evolution of life was linearly progressive, interrupted catastrophically only at the K-T boundary. The end-Triassic extinction was more like the Paleozoic extinctions in nature and probably also in its cause. By contrast, the current extinction resembles none of the earlier ones and may end up being the greatest of all.",
    url = "https://pmc.ncbi.nlm.nih.gov/articles/PMC2544523/",
    doi = "10.1073/pnas.0805482105",
    openalex = "W2067988424",
    pmcid = "PMC2544523",
    pmid = "18779562",
    references = "alvarez1980extraterrestrial, doi10100797894017960024, doi101017s0094837300003778, doi101029gm100, doi101093oso97801985491780010001, doi101126science21545391501, doi1023073515466, doi105860choice435903, doi105962bhltitle50860, doi107312webb12678"
}

The end-Permian mass extinction, 251 million years (Myr) ago, was the most devastating ecological event of all time, and it was exacerbated by two earlier events at the beginning and end of the Guadalupian, 270 and 260 Myr ago. Ecosystems were destroyed worldwide, communities were restructured and organisms were left struggling to recover. Disaster taxa, such as Lystrosaurus, insinuated themselves into almost every corner of the sparsely populated landscape in the earliest Triassic, and a quick taxonomic recovery apparently occurred on a global scale. However, close study of ecosystem evolution shows that true ecological recovery was slower. After the end-Guadalupian event, faunas began rebuilding complex trophic structures and refilling guilds, but were hit again by the end-Permian event. Taxonomic diversity at the alpha (community) level did not recover to pre-extinction levels; it reached only a low plateau after each pulse and continued low into the Late Triassic. Our data showed that though there was an initial rise in cosmopolitanism after the extinction pulses, large drops subsequently occurred and, counter-intuitively, a surprisingly low level of cosmopolitanism was sustained through the Early and Middle Triassic.

@article{doi101098rspb20071370,
    author = "Sahney, Sarda and Benton, Michael J.",
    title = "Recovery from the most profound mass extinction of all time",
    year = "2008",
    journal = "Proceedings of the Royal Society B Biological Sciences",
    abstract = "The end-Permian mass extinction, 251 million years (Myr) ago, was the most devastating ecological event of all time, and it was exacerbated by two earlier events at the beginning and end of the Guadalupian, 270 and 260 Myr ago. Ecosystems were destroyed worldwide, communities were restructured and organisms were left struggling to recover. Disaster taxa, such as Lystrosaurus, insinuated themselves into almost every corner of the sparsely populated landscape in the earliest Triassic, and a quick taxonomic recovery apparently occurred on a global scale. However, close study of ecosystem evolution shows that true ecological recovery was slower. After the end-Guadalupian event, faunas began rebuilding complex trophic structures and refilling guilds, but were hit again by the end-Permian event. Taxonomic diversity at the alpha (community) level did not recover to pre-extinction levels; it reached only a low plateau after each pulse and continued low into the Late Triassic. Our data showed that though there was an initial rise in cosmopolitanism after the extinction pulses, large drops subsequently occurred and, counter-intuitively, a surprisingly low level of cosmopolitanism was sustained through the Early and Middle Triassic.",
    url = "https://doi.org/10.1098/rspb.2007.1370",
    doi = "10.1098/rspb.2007.1370",
    openalex = "W2004445927",
    references = "benton1983dinosaur, doi101016s0169534703000934, doi101017cbo9780511735769004, doi101073pnas111144698, doi10108000241160410006483, doi101093oso97801985491780010001, doi101111j14754983200600611x, doi101126science11536548, doi101126science17740541065, doi101126science7701342, doi1023073515466, doi105860choice435903, openalexw1599677799"
}

The Cretaceous-Paleogene boundary approximately 65.5 million years ago marks one of the three largest mass extinctions in the past 500 million years. The extinction event coincided with a large asteroid impact at Chicxulub, Mexico, and occurred within the time of Deccan flood basalt volcanism in India. Here, we synthesize records of the global stratigraphy across this boundary to assess the proposed causes of the mass extinction. Notably, a single ejecta-rich deposit compositionally linked to the Chicxulub impact is globally distributed at the Cretaceous-Paleogene boundary. The temporal match between the ejecta layer and the onset of the extinctions and the agreement of ecological patterns in the fossil record with modeled environmental perturbations (for example, darkness and cooling) lead us to conclude that the Chicxulub impact triggered the mass extinction.

@article{doi101126science1177265,
    author = "Schulte, Peter and Alegret, Laia and Arenillas, Ignacio and Arz, José Antonio and Barton, P. J. and Bown, Paul R. and Bralower, Timothy J. and Christeson, Gail and Claeys, Philippe and Cockell, Charles S. and Collins, G. S. and Deutsch, A. and Goldin, Tamara and Goto, Kazuhisa and Grajales-Nishimura, José Manuel and Grieve, R. A. F. and Gulick, S. P. S. and Johnson, Kirk R. and Kiessling, Wolfgang and Koeberl, Christian and Kring, D. A. and MacLeod, Kenneth G. and Matsui, Takafumi and Melosh, J. and Montanari, Alessandro and Morgan, Joanna and Neal, C. R. and Nichols, Douglas J. and Norris, Richard D. and Pierazzo, E. and Ravizza, Greg and Rebolledo‐Vieyra, M. and Reimold, W. U. and Robin, Éric and Salge, T. and Speijer, Robert P. and Sweet, A R and Urrutia‐Fucugauchi, J. and Vajda, Vivi and Whalen, Michael T. and Willumsen, Pi Suhr",
    title = "The Chicxulub Asteroid Impact and Mass Extinction at the Cretaceous-Paleogene Boundary",
    year = "2010",
    journal = "Science",
    abstract = "The Cretaceous-Paleogene boundary approximately 65.5 million years ago marks one of the three largest mass extinctions in the past 500 million years. The extinction event coincided with a large asteroid impact at Chicxulub, Mexico, and occurred within the time of Deccan flood basalt volcanism in India. Here, we synthesize records of the global stratigraphy across this boundary to assess the proposed causes of the mass extinction. Notably, a single ejecta-rich deposit compositionally linked to the Chicxulub impact is globally distributed at the Cretaceous-Paleogene boundary. The temporal match between the ejecta layer and the onset of the extinctions and the agreement of ecological patterns in the fossil record with modeled environmental perturbations (for example, darkness and cooling) lead us to conclude that the Chicxulub impact triggered the mass extinction.",
    url = "https://doi.org/10.1126/science.1177265",
    doi = "10.1126/science.1177265",
    openalex = "W2160490562",
    references = "alvarez1980extraterrestrial, doi101016jepsl200605041, doi101016jepsl200607020, doi101016jepsl200902019, doi101016jpalaeo200702037, doi101016jpalaeo200709016, doi101017cbo9780511535536, doi1010292008jb005644, doi10102996rg03038, doi10102997je01743, doi101038285198a0, doi101073pnas0802597105, doi101126science1064706, doi101126science20844481095, doi1011300091761319910190867ccapct23co2, doi101130081372356655, doi1011302007242401, doi101146annurevearth27175, doi101146annurevecolsys35021103105715"
}

The greatest loss of biodiversity in the history of animal life occurred at the end of the Permian Period (∼252 million years ago). This biotic catastrophe coincided with an interval of widespread ocean anoxia and the eruption of one of Earth's largest continental flood basalt provinces, the Siberian Traps. Volatile release from basaltic magma and sedimentary strata during emplacement of the Siberian Traps can account for most end-Permian paleontological and geochemical observations. Climate change and, perhaps, destruction of the ozone layer can explain extinctions on land, whereas changes in ocean oxygen levels, CO 2, pH, and temperature can account for extinction selectivity across marine animals. These emerging insights from geology, geochemistry, and paleobiology suggest that the end-Permian extinction may serve as an important ancient analog for twenty-first century oceans.

@article{doi101146annurevearth042711105329,
    author = "Payne, Jonathan L. and Clapham, Matthew E.",
    title = "End-Permian Mass Extinction in the Oceans: An Ancient Analog for the Twenty-First Century?",
    year = "2012",
    journal = "Annual Review of Earth and Planetary Sciences",
    abstract = "The greatest loss of biodiversity in the history of animal life occurred at the end of the Permian Period (∼252 million years ago). This biotic catastrophe coincided with an interval of widespread ocean anoxia and the eruption of one of Earth's largest continental flood basalt provinces, the Siberian Traps. Volatile release from basaltic magma and sedimentary strata during emplacement of the Siberian Traps can account for most end-Permian paleontological and geochemical observations. Climate change and, perhaps, destruction of the ozone layer can explain extinctions on land, whereas changes in ocean oxygen levels, CO 2, pH, and temperature can account for extinction selectivity across marine animals. These emerging insights from geology, geochemistry, and paleobiology suggest that the end-Permian extinction may serve as an important ancient analog for twenty-first century oceans.",
    url = "https://doi.org/10.1146/annurev-earth-042711-105329",
    doi = "10.1146/annurev-earth-042711-105329",
    openalex = "W2116943064",
    references = "doi101016jchemgeo200311013, doi101016jearscirev200910009, doi101016jgca200511032, doi101016jgloplacha200606005, doi101016s0012825200000374, doi101017s0094837300003778, doi101038425365a, doi101038nature02566, doi101073pnas0701257104, doi101086319243, doi101126science1097023, doi101126science1177265, doi101126science1189910, doi101126science27252651155, doi101126science2765310235, doi101130g322301, doi105860choice435903, openalexw1832764887"
}

For the past three decades, the Alvarez impact theory of mass extinction, causally related to catastrophic meteorite impacts, has been recurrently applied to multiple extinction boundaries. However, these multidisciplinary research efforts across the globe have been largely unsuccessful to date, with one outstanding exception: the Cretaceous-Paleogene boundary. The unicausal impact scenario as a leading explanation, when applied to the complex fossil record, has resulted in force-fitting of data and interpretations ("great expectations syndrome"). The misunderstandings can be grouped at three successive levels of the testing process, and involve the unreflective application of the impact paradigm: (i) factual misidentification, i.e., an erroneous or indefinite recognition of the extraterrestrial record in sedimentological, physical and geochemical contexts, (ii) correlative misinterpretation of the adequately documented impact signals due to their incorrect dating, and (iii) causal overestimation when the proved impact characteristics are doubtful as a sufficient trigger of a contemporaneous global cosmic catastrophe. Examples of uncritical belief in the simple cause-effect scenario for the Frasnian-Famennian, Permian-Triassic, and Triassic-Jurassic (and the Eifelian-Givetian and Paleocene-Eocene as well) global events include mostly item-1 pitfalls (factual misidentification), with Ir enrichments and shocked minerals frequently misidentified. Therefore, these mass extinctions are still at the first test level, and only the F-F extinction is potentially seen in the context of item-2, the interpretative step, because of the possible causative link with the Siljan Ring crater (53 km in diameter). The erratically recognized cratering signature is often marked by large timing and size uncertainties, and item-3, the advanced causal inference, is in fact limited to clustered impacts that clearly predate major mass extinctions. The multi-impact lag-time pattern is particularly clear in the Late Triassic, when the largest (100 km diameter) Manicouagan crater was possibly concurrent with the end-Carnian extinction (or with the late Norian tetrapod turnover on an alternative time scale). The relatively small crater sizes and cratonic (crystalline rock basement) setting of these two craters further suggest the strongly insufficient extraterrestrial trigger of worldwide environmental traumas. However, to discuss the kill potential of impact events in a more robust fashion, their location and timing, vulnerability factors, especially target geology and palaeogeography in the context of associated climate-active volatile fluxes, should to be rigorously assessed. The current lack of conclusive impact evidence synchronous with most mass extinctions may still be somewhat misleading due to the predicted large set of undiscovered craters, particularly in light of the obscured record of oceanic impact events.

@article{doi104202app20110058,
    author = "Racki, Grzegorz",
    title = "The Alvarez Impact Theory of Mass Extinction; Limits to its Applicability and the “Great Expectations Syndrome”",
    year = "2012",
    journal = "Acta Palaeontologica Polonica",
    abstract = {For the past three decades, the Alvarez impact theory of mass extinction, causally related to catastrophic meteorite impacts, has been recurrently applied to multiple extinction boundaries. However, these multidisciplinary research efforts across the globe have been largely unsuccessful to date, with one outstanding exception: the Cretaceous-Paleogene boundary. The unicausal impact scenario as a leading explanation, when applied to the complex fossil record, has resulted in force-fitting of data and interpretations ("great expectations syndrome"). The misunderstandings can be grouped at three successive levels of the testing process, and involve the unreflective application of the impact paradigm: (i) factual misidentification, i.e., an erroneous or indefinite recognition of the extraterrestrial record in sedimentological, physical and geochemical contexts, (ii) correlative misinterpretation of the adequately documented impact signals due to their incorrect dating, and (iii) causal overestimation when the proved impact characteristics are doubtful as a sufficient trigger of a contemporaneous global cosmic catastrophe. Examples of uncritical belief in the simple cause-effect scenario for the Frasnian-Famennian, Permian-Triassic, and Triassic-Jurassic (and the Eifelian-Givetian and Paleocene-Eocene as well) global events include mostly item-1 pitfalls (factual misidentification), with Ir enrichments and shocked minerals frequently misidentified. Therefore, these mass extinctions are still at the first test level, and only the F-F extinction is potentially seen in the context of item-2, the interpretative step, because of the possible causative link with the Siljan Ring crater (53 km in diameter). The erratically recognized cratering signature is often marked by large timing and size uncertainties, and item-3, the advanced causal inference, is in fact limited to clustered impacts that clearly predate major mass extinctions. The multi-impact lag-time pattern is particularly clear in the Late Triassic, when the largest (100 km diameter) Manicouagan crater was possibly concurrent with the end-Carnian extinction (or with the late Norian tetrapod turnover on an alternative time scale). The relatively small crater sizes and cratonic (crystalline rock basement) setting of these two craters further suggest the strongly insufficient extraterrestrial trigger of worldwide environmental traumas. However, to discuss the kill potential of impact events in a more robust fashion, their location and timing, vulnerability factors, especially target geology and palaeogeography in the context of associated climate-active volatile fluxes, should to be rigorously assessed. The current lack of conclusive impact evidence synchronous with most mass extinctions may still be somewhat misleading due to the predicted large set of undiscovered craters, particularly in light of the obscured record of oceanic impact events.},
    url = "https://doi.org/10.4202/app.2011.0058",
    doi = "10.4202/app.2011.0058",
    openalex = "W1991076266",
    references = "alvarez1980extraterrestrial, doi101016jearscirev200811004, doi101016s0031018297000503, doi101038nature10385, doi101073pnas0805482105, doi101093oso97801985491780010001, doi101126science1177265, doi101126science21545391501, doi101126science2895478432, doi1011300091761319910190867ccapct23co2, doi101144gsjgs14650749, doi1023073515466, doi105860choice293880, openalexw2912219260"
}

Examining biological diversity in an explicitly evolutionary context has been the subject of research for several decades, yet relatively recent advances in analytical techniques and the increasing availability of species-level phylogenies, have enabled scientists to ask new questions. One such approach is to quantify phylogenetic signal to determine how trait variation is correlated with the phylogenetic relatedness of species. When phylogenetic signal is high, closely related species exhibit similar traits, and this biological similarity decreases as the evolutionary distance between species increases. Here, we first review the concept of phylogenetic signal and suggest how to measure and interpret phylogenetic signal in species traits. Second, we quantified phylogenetic signal in primates for 31 variables, including body mass, brain size, life-history, sexual selection, social organization, diet, activity budget, ranging patterns and climatic variables. We found that phylogenetic signal varies extensively across and even within trait categories. The highest values are exhibited by brain size and body mass, moderate values are found in the degree of territoriality and canine size dimorphism, while low values are displayed by most of the remaining variables. Our results have important implications for the evolution of behaviour and ecology in primates and other vertebrates.

@article{doi101098rstb20120341,
    author = "Kamilar, Jason M. and Cooper, Natalie",
    title = "Phylogenetic signal in primate behaviour, ecology and life history",
    year = "2013",
    journal = "Philosophical Transactions of the Royal Society B Biological Sciences",
    abstract = "Examining biological diversity in an explicitly evolutionary context has been the subject of research for several decades, yet relatively recent advances in analytical techniques and the increasing availability of species-level phylogenies, have enabled scientists to ask new questions. One such approach is to quantify phylogenetic signal to determine how trait variation is correlated with the phylogenetic relatedness of species. When phylogenetic signal is high, closely related species exhibit similar traits, and this biological similarity decreases as the evolutionary distance between species increases. Here, we first review the concept of phylogenetic signal and suggest how to measure and interpret phylogenetic signal in species traits. Second, we quantified phylogenetic signal in primates for 31 variables, including body mass, brain size, life-history, sexual selection, social organization, diet, activity budget, ranging patterns and climatic variables. We found that phylogenetic signal varies extensively across and even within trait categories. The highest values are exhibited by brain size and body mass, moderate values are found in the degree of territoriality and canine size dimorphism, while low values are displayed by most of the remaining variables. Our results have important implications for the evolution of behaviour and ecology in primates and other vertebrates.",
    url = "https://doi.org/10.1098/rstb.2012.0341",
    doi = "10.1098/rstb.2012.0341",
    openalex = "W2162795003",
    references = "doi101086285558, doi101086660020"
}

Contemporary biodiversity loss and population declines threaten to push the biosphere toward a tipping point with irreversible effects on ecosystem composition and function. As a potential example of a global-scale regime shift in the geological past, we assessed ecological changes across the end-Cretaceous mass extinction based on molluscan assemblages at four well-studied sites. By contrasting preextinction and postextinction rank abundance and numerical abundance in 19 molluscan modes of life--each defined as a unique combination of mobility level, feeding mode, and position relative to the substrate--we find distinct shifts in ecospace utilization, which significantly exceed predictions from null models. The magnitude of change in functional traits relative to normal temporal fluctuations at far-flung sites indicates that molluscan assemblages shifted to differently structured systems and faunal response was global. The strengths of temporal ecological shifts, however, are mostly within the range of preextinction site-to-site variability, demonstrating that local ecological turnover was similar to geographic variation over a broad latitudinal range. In conjunction with varied site-specific temporal patterns of individual modes of life, these spatial and temporal heterogeneities argue against a concerted phase shift of molluscan assemblages from one well-defined regime to another. At a broader ecological level, by contrast, congruent tendencies emerge and suggest deterministic processes. These patterns comprise the well-known increase of deposit-feeding mollusks in postextinction assemblages and increases in predators and predator-resistant modes of life, i.e., those characterized by elevated mobility and infaunal life habits.

@article{doi101073pnas1422248112,
    author = "Aberhan, Martin and Kiessling, Wolfgang",
    title = "Persistent ecological shifts in marine molluscan assemblages across the end-Cretaceous mass extinction",
    year = "2015",
    journal = "Proceedings of the National Academy of Sciences",
    abstract = "Contemporary biodiversity loss and population declines threaten to push the biosphere toward a tipping point with irreversible effects on ecosystem composition and function. As a potential example of a global-scale regime shift in the geological past, we assessed ecological changes across the end-Cretaceous mass extinction based on molluscan assemblages at four well-studied sites. By contrasting preextinction and postextinction rank abundance and numerical abundance in 19 molluscan modes of life--each defined as a unique combination of mobility level, feeding mode, and position relative to the substrate--we find distinct shifts in ecospace utilization, which significantly exceed predictions from null models. The magnitude of change in functional traits relative to normal temporal fluctuations at far-flung sites indicates that molluscan assemblages shifted to differently structured systems and faunal response was global. The strengths of temporal ecological shifts, however, are mostly within the range of preextinction site-to-site variability, demonstrating that local ecological turnover was similar to geographic variation over a broad latitudinal range. In conjunction with varied site-specific temporal patterns of individual modes of life, these spatial and temporal heterogeneities argue against a concerted phase shift of molluscan assemblages from one well-defined regime to another. At a broader ecological level, by contrast, congruent tendencies emerge and suggest deterministic processes. These patterns comprise the well-known increase of deposit-feeding mollusks in postextinction assemblages and increases in predators and predator-resistant modes of life, i.e., those characterized by elevated mobility and infaunal life habits.",
    url = "https://doi.org/10.1073/pnas.1422248112",
    doi = "10.1073/pnas.1422248112",
    openalex = "W1551201887",
    references = "doi101002jgrg20086, doi101016s0031018299000887"
}

The oft-repeated claim that Earth's biota is entering a sixth "mass extinction" depends on clearly demonstrating that current extinction rates are far above the "background" rates prevailing between the five previous mass extinctions. Earlier estimates of extinction rates have been criticized for using assumptions that might overestimate the severity of the extinction crisis. We assess, using extremely conservative assumptions, whether human activities are causing a mass extinction. First, we use a recent estimate of a background rate of 2 mammal extinctions per 10,000 species per 100 years (that is, 2 E/MSY), which is twice as high as widely used previous estimates. We then compare this rate with the current rate of mammal and vertebrate extinctions. The latter is conservatively low because listing a species as extinct requires meeting stringent criteria. Even under our assumptions, which would tend to minimize evidence of an incipient mass extinction, the average rate of vertebrate species loss over the last century is up to 100 times higher than the background rate. Under the 2 E/MSY background rate, the number of species that have gone extinct in the last century would have taken, depending on the vertebrate taxon, between 800 and 10,000 years to disappear. These estimates reveal an exceptionally rapid loss of biodiversity over the last few centuries, indicating that a sixth mass extinction is already under way. Averting a dramatic decay of biodiversity and the subsequent loss of ecosystem services is still possible through intensified conservation efforts, but that window of opportunity is rapidly closing.

@article{doi101126sciadv1400253,
    author = "Ceballos, Gerardo and Ehrlich, Paul R. and Barnosky, Anthony D. and García, Andrés and Pringle, Robert M. and Palmer, Todd M.",
    title = "Accelerated modern human–induced species losses: Entering the sixth mass extinction",
    year = "2015",
    journal = "Science Advances",
    abstract = {The oft-repeated claim that Earth's biota is entering a sixth "mass extinction" depends on clearly demonstrating that current extinction rates are far above the "background" rates prevailing between the five previous mass extinctions. Earlier estimates of extinction rates have been criticized for using assumptions that might overestimate the severity of the extinction crisis. We assess, using extremely conservative assumptions, whether human activities are causing a mass extinction. First, we use a recent estimate of a background rate of 2 mammal extinctions per 10,000 species per 100 years (that is, 2 E/MSY), which is twice as high as widely used previous estimates. We then compare this rate with the current rate of mammal and vertebrate extinctions. The latter is conservatively low because listing a species as extinct requires meeting stringent criteria. Even under our assumptions, which would tend to minimize evidence of an incipient mass extinction, the average rate of vertebrate species loss over the last century is up to 100 times higher than the background rate. Under the 2 E/MSY background rate, the number of species that have gone extinct in the last century would have taken, depending on the vertebrate taxon, between 800 and 10,000 years to disappear. These estimates reveal an exceptionally rapid loss of biodiversity over the last few centuries, indicating that a sixth mass extinction is already under way. Averting a dramatic decay of biodiversity and the subsequent loss of ecosystem services is still possible through intensified conservation efforts, but that window of opportunity is rapidly closing.},
    url = "https://doi.org/10.1126/sciadv.1400253",
    doi = "10.1126/sciadv.1400253",
    openalex = "W2175423925",
    references = "doi101038nature09678, doi101098rspb20122845, doi101126science1069349, doi101126science1103538, doi101126science1251817"
}

The temporal link between large igneous province (LIP) eruptions and at least half of the major extinctions of the Phanerozoic implies that large scale volcanism is the main driver of mass extinction. Here we review almost twenty biotic crises between the early Cambrian and end Cretaceous and explore potential causal mechanisms. Most extinctions are associated with global warming and proximal killers such as marine anoxia (including the Early/Middle Cambrian, the Late Ordovician, the intra-Silurian, intra-Devonian, end-Permian, and Early Jurassic crises). Many, but not all of these are accompanied by large negative carbon isotope excursions, supporting a volcanogenic origin. Most post-Silurian biocrises affected both terrestrial and marine biospheres, suggesting that atmospheric processes were crucial in driving global extinctions. Volcanogenic-atmospheric kill mechanisms include ocean acidification, toxic metal poisoning, acid rain, and ozone damage and consequent increased UV-B radiation, volcanic darkness, cooling and photosynthetic shutdown, each of which has been implicated in numerous events. Intriguingly, some of the most voluminous LIPs such as the oceanic plateaus of the Cretaceous were emplaced with minimal faunal losses and so volume of magma is not the only factor governing LIP lethality. The missing link might be continental configuration because the best examples of the LIP/extinction relationship occurred during the time of Pangaea. Many of the proximal kill mechanisms in LIP/extinction scenarios are also potential effects of bolide impact, including cooling, warming, acidification and ozone destruction. However, the absence of convincing temporal links between impacts and extinctions other than the Chicxulub-Cretaceous example, suggests that impacts are not the main driver of extinctions. With numerous competing extinction scenarios, and the realisation that some of the purported environmental stresses may once again be driving mass extinction, we explore how experimental biology might inform our understanding of ancient extinctions as well as future crises.

@article{doi101016jpalaeo201611005,
    author = "Bond, David P.G. and Grasby, Stephen E.",
    title = "On the causes of mass extinctions",
    year = "2016",
    journal = "Palaeogeography Palaeoclimatology Palaeoecology",
    abstract = "The temporal link between large igneous province (LIP) eruptions and at least half of the major extinctions of the Phanerozoic implies that large scale volcanism is the main driver of mass extinction. Here we review almost twenty biotic crises between the early Cambrian and end Cretaceous and explore potential causal mechanisms. Most extinctions are associated with global warming and proximal killers such as marine anoxia (including the Early/Middle Cambrian, the Late Ordovician, the intra-Silurian, intra-Devonian, end-Permian, and Early Jurassic crises). Many, but not all of these are accompanied by large negative carbon isotope excursions, supporting a volcanogenic origin. Most post-Silurian biocrises affected both terrestrial and marine biospheres, suggesting that atmospheric processes were crucial in driving global extinctions. Volcanogenic-atmospheric kill mechanisms include ocean acidification, toxic metal poisoning, acid rain, and ozone damage and consequent increased UV-B radiation, volcanic darkness, cooling and photosynthetic shutdown, each of which has been implicated in numerous events. Intriguingly, some of the most voluminous LIPs such as the oceanic plateaus of the Cretaceous were emplaced with minimal faunal losses and so volume of magma is not the only factor governing LIP lethality. The missing link might be continental configuration because the best examples of the LIP/extinction relationship occurred during the time of Pangaea. Many of the proximal kill mechanisms in LIP/extinction scenarios are also potential effects of bolide impact, including cooling, warming, acidification and ozone destruction. However, the absence of convincing temporal links between impacts and extinctions other than the Chicxulub-Cretaceous example, suggests that impacts are not the main driver of extinctions. With numerous competing extinction scenarios, and the realisation that some of the purported environmental stresses may once again be driving mass extinction, we explore how experimental biology might inform our understanding of ancient extinctions as well as future crises.",
    url = "https://doi.org/10.1016/j.palaeo.2016.11.005",
    doi = "10.1016/j.palaeo.2016.11.005",
    openalex = "W2552047291",
    references = "alvarez1980extraterrestrial, doi101007bf01821208, doi1010160031018284900415, doi1010160034666780900226, doi101016jearscirev200708008, doi101016jearscirev200910009, doi101016jepsl200905028, doi101016jgca201006017, doi101016jgca201106021, doi101016jgeobios201111001, doi101016jpalaeo200507010, doi101016jpalaeo200702037, doi101016jpalaeo201703014, doi101016s0012825202001046, doi101016s0031018298001175, doi101016s0169534703000934, doi101016s0967065397848259, doi101017s0016756807003895, doi101017s0094837300003778, doi1010291998rg000054, doi10102996rg03038, doi10102997je01743, doi101029gb002i004p00299, doi101038227930a0, doi101038367231a0, doi101038nature04095, doi101038nature09678, doi101038ngeo1475, doi101038ngeo1649, doi101073pnas1110395108, doi101073pnas1211526110, doi10108010292389409380462, doi101086648217, doi101098rstb19890092, doi101098rstb19980195, doi101111j150239312002tb00081x, doi101126sciadv1400253, doi101126science1097329, doi101126science1213454, doi101126science1230492, doi101126science1234204, doi101126science20844481095, doi101126science21545391501, doi101126scienceaaa0118, doi10113000167606198596567defie20co2, doi1011300091761319910190867ccapct23co2, doi1011300091761319950230495ejmeag23co2, doi1011300091761319980260995adswat23co2, doi1011300091761320020300251tameat20co2, doi101130081372356655, doi1011302014250502, doi101130g322301, doi101130g327071, doi101130spe89p63, doi101144gsjgs15420265, doi101146annurevearth042711105329, doi1016660094837320040300522oeamdo20co2, openalexw1832764887, openalexw2596223166"
}

Debate continues about the nature of the Cretaceous-Paleogene (K-Pg) mass extinction event. An abrupt crisis triggered by a bolide impact contrasts with ideas of a more gradual extinction involving flood volcanism or climatic changes. Evidence from high latitudes has also been used to suggest that the severity of the extinction decreased from low latitudes towards the poles. Here we present a record of the K-Pg extinction based on extensive assemblages of marine macrofossils (primarily new data from benthic molluscs) from a highly expanded Cretaceous-Paleogene succession: the López de Bertodano Formation of Seymour Island, Antarctica. We show that the extinction was rapid and severe in Antarctica, with no significant biotic decline during the latest Cretaceous, contrary to previous studies. These data are consistent with a catastrophic driver for the extinction, such as bolide impact, rather than a significant contribution from Deccan Traps volcanism during the late Maastrichtian.

@article{doi101038ncomms11738,
    author = "Witts, James D. and Whittle, Rowan J. and Wignall, Paul B. and Crame, J. Alistair and Francis, Jane E. and Newton, Robert J. and Bowman, Vanessa C.",
    title = "Macrofossil evidence for a rapid and severe Cretaceous–Paleogene mass extinction in Antarctica",
    year = "2016",
    journal = "Nature Communications",
    abstract = "Debate continues about the nature of the Cretaceous-Paleogene (K-Pg) mass extinction event. An abrupt crisis triggered by a bolide impact contrasts with ideas of a more gradual extinction involving flood volcanism or climatic changes. Evidence from high latitudes has also been used to suggest that the severity of the extinction decreased from low latitudes towards the poles. Here we present a record of the K-Pg extinction based on extensive assemblages of marine macrofossils (primarily new data from benthic molluscs) from a highly expanded Cretaceous-Paleogene succession: the López de Bertodano Formation of Seymour Island, Antarctica. We show that the extinction was rapid and severe in Antarctica, with no significant biotic decline during the latest Cretaceous, contrary to previous studies. These data are consistent with a catastrophic driver for the extinction, such as bolide impact, rather than a significant contribution from Deccan Traps volcanism during the late Maastrichtian.",
    url = "https://doi.org/10.1038/ncomms11738",
    doi = "10.1038/ncomms11738",
    openalex = "W2398503768",
    references = "doi101016jpalaeo200909025, doi101016s0031018299000887, doi101017s0022336000024331"
}

Procedures introduced here make it possible, first, to show that background (piecemeal) extinction is recorded throughout geologic stages and substages (not all extinction has occurred suddenly at the ends of such intervals); second, to separate out background extinction from mass extinction for a major crisis in earth history; and third, to correct for clustering of extinctions when using the rarefaction method to estimate the percentage of species lost in a mass extinction. Also presented here is a method for estimating the magnitude of the Signor-Lipps effect, which is the incorrect assignment of extinctions that occurred during a crisis to an interval preceding the crisis because of the incompleteness of the fossil record. Estimates for the magnitudes of mass extinctions presented here are in most cases lower than those previously published. They indicate that only ∼81% of marine species died out in the great terminal Permian crisis, whereas levels of 90-96% have frequently been quoted in the literature. Calculations of the latter numbers were incorrectly based on combined data for the Middle and Late Permian mass extinctions. About 90 orders and more than 220 families of marine animals survived the terminal Permian crisis, and they embodied an enormous amount of morphological, physiological, and ecological diversity. Life did not nearly disappear at the end of the Permian, as has often been claimed.

@article{doi101073pnas1613094113,
    author = "Stanley, Steven M.",
    title = "Estimates of the magnitudes of major marine mass extinctions in earth history",
    year = "2016",
    journal = "Proceedings of the National Academy of Sciences",
    abstract = "Procedures introduced here make it possible, first, to show that background (piecemeal) extinction is recorded throughout geologic stages and substages (not all extinction has occurred suddenly at the ends of such intervals); second, to separate out background extinction from mass extinction for a major crisis in earth history; and third, to correct for clustering of extinctions when using the rarefaction method to estimate the percentage of species lost in a mass extinction. Also presented here is a method for estimating the magnitude of the Signor-Lipps effect, which is the incorrect assignment of extinctions that occurred during a crisis to an interval preceding the crisis because of the incompleteness of the fossil record. Estimates for the magnitudes of mass extinctions presented here are in most cases lower than those previously published. They indicate that only ∼81\% of marine species died out in the great terminal Permian crisis, whereas levels of 90-96\% have frequently been quoted in the literature. Calculations of the latter numbers were incorrectly based on combined data for the Middle and Late Permian mass extinctions. About 90 orders and more than 220 families of marine animals survived the terminal Permian crisis, and they embodied an enormous amount of morphological, physiological, and ecological diversity. Life did not nearly disappear at the end of the Permian, as has often been claimed.",
    url = "https://doi.org/10.1073/pnas.1613094113",
    doi = "10.1073/pnas.1613094113",
    openalex = "W2529501031",
    references = "doi101002gj1090, doi101007978364270831215, doi101016s001282520000026x, doi101016s0012825203000825, doi101017s0094837300013178, doi101130g211551, doi101146annurevearth33092203122654, doi1016660094837320050310006poaeit20co2, doi105860choice435903"
}

A quantitative scale for measuring greatness, G, of mass extinctions is proposed on the basis of rate of biodiversity diminution expressed as the product of the loss of biodiversity, called magnitude (M), and the inverse of time in which that loss occurs, designated as intensity (/). On this scale, the catastrophic Cretaceous-Tertiary (K-T) extinction appears as the greatest since the Ordovician and the only one with a probable extraterrestrial cause. The end-Permian extinction was less great but with a large magnitude (M) and smaller intensity (0; only some of its individual episodes involved some semblance of catas trophe. Other extinctions during the Phanerozoic, with the possible exception of the end-Silurian diversity plunge, were parts of a forced oscillatory phenomenon and seem caused by marineand land habitat destruction during continental assemblies that led to elimi nation of shelves and (after the Devonian) rain forests and enlarge ment of deserts. Glaciations and orogenies that shortened and thickened the continental crust only exacerbated these effects. Dur ing the Mesozoic and Cainozoic, the evolution of life was linearly progressive, interrupted catastrophically only at the K-T boundary. The end-Triassic extinction was more like the Paleozoic extinctions in nature and probably also in its cause. By contrast, the current extinc tion resembles none of the earlier ones and may end up being the greatest of all.

@article{openalexw3152344003,
    author = "zeren, Sinan",
    title = "A scale of greatness and causal classification of mass extinctions: Implications for mechanisms",
    year = "2016",
    abstract = "A quantitative scale for measuring greatness, G, of mass extinctions is proposed on the basis of rate of biodiversity diminution expressed as the product of the loss of biodiversity, called magnitude (M), and the inverse of time in which that loss occurs, designated as intensity (/). On this scale, the catastrophic Cretaceous-Tertiary (K-T) extinction appears as the greatest since the Ordovician and the only one with a probable extraterrestrial cause. The end-Permian extinction was less great but with a large magnitude (M) and smaller intensity (0; only some of its individual episodes involved some semblance of catas trophe. Other extinctions during the Phanerozoic, with the possible exception of the end-Silurian diversity plunge, were parts of a forced oscillatory phenomenon and seem caused by marineand land habitat destruction during continental assemblies that led to elimi nation of shelves and (after the Devonian) rain forests and enlarge ment of deserts. Glaciations and orogenies that shortened and thickened the continental crust only exacerbated these effects. Dur ing the Mesozoic and Cainozoic, the evolution of life was linearly progressive, interrupted catastrophically only at the K-T boundary. The end-Triassic extinction was more like the Paleozoic extinctions in nature and probably also in its cause. By contrast, the current extinc tion resembles none of the earlier ones and may end up being the greatest of all.",
    openalex = "W3152344003",
    references = "doi101016jearscirev200705002, doi1010292001gl012921, doi101073pnas0805482105, doi101073pnas111144698, doi101086345841, doi101098rstb19940045, doi101111j14724677200400020x, doi101130spe448, doi1016660094837320040300522oeamdo20co2, doi105860choice435903, openalexw636094484"
}

C excursions. The latter excursion is paced by obliquity and is therein similar to Mesozoic intervals of environmental upheaval, like the Cretaceous Ocean-Anoxic-Event-2 (OAE-2). This obliquity signature implies coincidence with a minimum of the 2.4 Myr eccentricity cycle, during which obliquity prevails over precession, and highlights the decisive role of astronomically forced "Milankovitch" climate change in timing and pacing the Late Devonian mass extinction.

@article{doi101038s41467017024071,
    author = "Vleeschouwer, David De and Silva, Anne‐Christine Da and Sinnesael, Matthias and Chen, Daizhao and Day, James E. and Whalen, Michael T. and Guo, Zenghui and Claeys, Philippe",
    title = "Timing and pacing of the Late Devonian mass extinction event regulated by eccentricity and obliquity",
    year = "2017",
    journal = "Nature Communications",
    abstract = {C excursions. The latter excursion is paced by obliquity and is therein similar to Mesozoic intervals of environmental upheaval, like the Cretaceous Ocean-Anoxic-Event-2 (OAE-2). This obliquity signature implies coincidence with a minimum of the 2.4 Myr eccentricity cycle, during which obliquity prevails over precession, and highlights the decisive role of astronomically forced "Milankovitch" climate change in timing and pacing the Late Devonian mass extinction.},
    url = "https://doi.org/10.1038/s41467-017-02407-1",
    doi = "10.1038/s41467-017-02407-1",
    openalex = "W2779472444",
    references = "doi101007bfb0011143, doi102110jsr2010093"
}

The population extinction pulse we describe here shows, from a quantitative viewpoint, that Earth's sixth mass extinction is more severe than perceived when looking exclusively at species extinctions. Therefore, humanity needs to address anthropogenic population extirpation and decimation immediately. That conclusion is based on analyses of the numbers and degrees of range contraction (indicative of population shrinkage and/or population extinctions according to the International Union for Conservation of Nature) using a sample of 27,600 vertebrate species, and on a more detailed analysis documenting the population extinctions between 1900 and 2015 in 177 mammal species. We find that the rate of population loss in terrestrial vertebrates is extremely high-even in "species of low concern." In our sample, comprising nearly half of known vertebrate species, 32% (8,851/27,600) are decreasing; that is, they have decreased in population size and range. In the 177 mammals for which we have detailed data, all have lost 30% or more of their geographic ranges and more than 40% of the species have experienced severe population declines (>80% range shrinkage). Our data indicate that beyond global species extinctions Earth is experiencing a huge episode of population declines and extirpations, which will have negative cascading consequences on ecosystem functioning and services vital to sustaining civilization. We describe this as a "biological annihilation" to highlight the current magnitude of Earth's ongoing sixth major extinction event.

@article{doi101073pnas1704949114,
    author = "Ceballos, Gerardo and Ehrlich, Paul R. and Dirzo, Rodolfo",
    title = "Biological annihilation via the ongoing sixth mass extinction signaled by vertebrate population losses and declines",
    year = "2017",
    journal = "Proceedings of the National Academy of Sciences",
    abstract = {The population extinction pulse we describe here shows, from a quantitative viewpoint, that Earth's sixth mass extinction is more severe than perceived when looking exclusively at species extinctions. Therefore, humanity needs to address anthropogenic population extirpation and decimation immediately. That conclusion is based on analyses of the numbers and degrees of range contraction (indicative of population shrinkage and/or population extinctions according to the International Union for Conservation of Nature) using a sample of 27,600 vertebrate species, and on a more detailed analysis documenting the population extinctions between 1900 and 2015 in 177 mammal species. We find that the rate of population loss in terrestrial vertebrates is extremely high-even in "species of low concern." In our sample, comprising nearly half of known vertebrate species, 32\% (8,851/27,600) are decreasing; that is, they have decreased in population size and range. In the 177 mammals for which we have detailed data, all have lost 30\% or more of their geographic ranges and more than 40\% of the species have experienced severe population declines (>80\% range shrinkage). Our data indicate that beyond global species extinctions Earth is experiencing a huge episode of population declines and extirpations, which will have negative cascading consequences on ecosystem functioning and services vital to sustaining civilization. We describe this as a "biological annihilation" to highlight the current magnitude of Earth's ongoing sixth major extinction event.},
    url = "https://doi.org/10.1073/pnas.1704949114",
    doi = "10.1073/pnas.1704949114",
    openalex = "W2724327356",
    references = "doi1010029780470999592, doi101038nature09678, doi101126science1069349, doi101126science1094875, doi101126science1251817, doi1016410006356820040540123rconac20co2"
}

The Cretaceous–Paleogene (K–Pg) mass extinction event 66 million years ago led to large changes to the global carbon cycle, primarily via a decrease in primary or export productivity of the oceans. However, the effects of this event and longer-term environmental changes during the Late Cretaceous on the global sulfur cycle are not well understood. We report new carbonate associated sulfate (CAS) sulfur isotope data derived from marine macrofossil shell material from a highly expanded high latitude Maastrichtian to Danian (69–65.5 Ma) succession located on Seymour Island, Antarctica. These data represent the highest resolution seawater sulfate record ever generated for this time interval, and are broadly in agreement with previous low-resolution estimates for the latest Cretaceous and Paleocene. A vigorous assessment of CAS preservation using sulfate oxygen, carbonate carbon and oxygen isotopes and trace element data, suggests factors affecting preservation of primary seawater CAS isotopes in ancient biogenic samples are complex, and not necessarily linked to the preservation of original carbonate mineralogy or chemistry. Primary data indicate a generally stable sulfur cycle in the early-mid Maastrichtian (69 Ma), with some fluctuations that could be related to increased pyrite burial during the ‘mid-Maastrichtian Event’. This is followed by an enigmatic +4‰ increase in δ34SCAS during the late Maastrichtian (68–66 Ma), culminating in a peak in values in the immediate aftermath of the K–Pg extinction which may be related to temporary development of oceanic anoxia in the aftermath of the Chicxulub bolide impact. There is no evidence of the direct influence of Deccan volcanism on the seawater sulfate isotopic record during the late Maastrichtian, nor of a direct influence by the Chicxulub impact itself. During the early Paleocene (magnetochron C29R) a prominent negative excursion in seawater δ34S of 3–4‰ suggests that a global decline in organic carbon burial related to collapse in export productivity, also impacted the sulfur cycle via a significant drop in pyrite burial. Box modelling suggests that to achieve an excursion of this magnitude, pyrite burial must be reduced by >15%, with a possible role for a short term increase in global weathering rates. Recovery of the sulfur cycle to pre-extinction values occurs at the same time (∼320 kyrs) as initial carbon cycle recovery globally. These recoveries are also contemporaneous with an initial increase in local alpha diversity of marine macrofossil faunas, suggesting biosphere-geosphere links during recovery from the mass extinction. Modelling further indicates that concentrations of sulfate in the oceans must have been 2 mM, lower than previous estimates for the Late Cretaceous and Paleocene and an order of magnitude lower than today.

@article{doi101016jgca201802037,
    author = "Witts, James D. and Newton, Robert J. and Mills, Benjamin and Wignall, Paul B. and Bottrell, Simon H. and Hall, Joanna L.O. and Francis, Jane E. and Crame, J. Alistair",
    title = "The impact of the Cretaceous–Paleogene (K–Pg) mass extinction event on the global sulfur cycle: Evidence from Seymour Island, Antarctica",
    year = "2018",
    journal = "Geochimica et Cosmochimica Acta",
    abstract = "The Cretaceous–Paleogene (K–Pg) mass extinction event 66 million years ago led to large changes to the global carbon cycle, primarily via a decrease in primary or export productivity of the oceans. However, the effects of this event and longer-term environmental changes during the Late Cretaceous on the global sulfur cycle are not well understood. We report new carbonate associated sulfate (CAS) sulfur isotope data derived from marine macrofossil shell material from a highly expanded high latitude Maastrichtian to Danian (69–65.5 Ma) succession located on Seymour Island, Antarctica. These data represent the highest resolution seawater sulfate record ever generated for this time interval, and are broadly in agreement with previous low-resolution estimates for the latest Cretaceous and Paleocene. A vigorous assessment of CAS preservation using sulfate oxygen, carbonate carbon and oxygen isotopes and trace element data, suggests factors affecting preservation of primary seawater CAS isotopes in ancient biogenic samples are complex, and not necessarily linked to the preservation of original carbonate mineralogy or chemistry. Primary data indicate a generally stable sulfur cycle in the early-mid Maastrichtian (69 Ma), with some fluctuations that could be related to increased pyrite burial during the ‘mid-Maastrichtian Event’. This is followed by an enigmatic +4‰ increase in δ34SCAS during the late Maastrichtian (68–66 Ma), culminating in a peak in values in the immediate aftermath of the K–Pg extinction which may be related to temporary development of oceanic anoxia in the aftermath of the Chicxulub bolide impact. There is no evidence of the direct influence of Deccan volcanism on the seawater sulfate isotopic record during the late Maastrichtian, nor of a direct influence by the Chicxulub impact itself. During the early Paleocene (magnetochron C29R) a prominent negative excursion in seawater δ34S of 3–4‰ suggests that a global decline in organic carbon burial related to collapse in export productivity, also impacted the sulfur cycle via a significant drop in pyrite burial. Box modelling suggests that to achieve an excursion of this magnitude, pyrite burial must be reduced by >15\%, with a possible role for a short term increase in global weathering rates. Recovery of the sulfur cycle to pre-extinction values occurs at the same time (∼320 kyrs) as initial carbon cycle recovery globally. These recoveries are also contemporaneous with an initial increase in local alpha diversity of marine macrofossil faunas, suggesting biosphere-geosphere links during recovery from the mass extinction. Modelling further indicates that concentrations of sulfate in the oceans must have been 2 mM, lower than previous estimates for the Late Cretaceous and Paleocene and an order of magnitude lower than today.",
    url = "https://doi.org/10.1016/j.gca.2018.02.037",
    doi = "10.1016/j.gca.2018.02.037",
    openalex = "W2790990289",
    references = "doi101016jcretres201204009"
}

concentration curve for the Early Triassic suggest that elevated marine productivity and enhanced oceanic stratification were likely the immediate causes of expanded oceanic anoxia. The patterns of redox variation documented by the U-isotope record show a good first-order correspondence to peaks in ammonoid extinctions during the Early Triassic. Our results indicate that multiple oscillations in oceanic anoxia modulated the recovery of marine ecosystems following the latest Permian mass extinction.

@article{doi101126sciadv1602921,
    author = "Zhang, Feifei and Romaniello, Stephen J. and Algeo, Thomas J. and Lau, Kimberly and Clapham, Matthew E. and Richoz, Sylvain and Herrmann, Achim D. and Smith, Harrison B. and Horacek, M. and Anbar, Ariel D.",
    title = "Multiple episodes of extensive marine anoxia linked to global warming and continental weathering following the latest Permian mass extinction",
    year = "2018",
    journal = "Science Advances",
    abstract = "concentration curve for the Early Triassic suggest that elevated marine productivity and enhanced oceanic stratification were likely the immediate causes of expanded oceanic anoxia. The patterns of redox variation documented by the U-isotope record show a good first-order correspondence to peaks in ammonoid extinctions during the Early Triassic. Our results indicate that multiple oscillations in oceanic anoxia modulated the recovery of marine ecosystems following the latest Permian mass extinction.",
    url = "https://doi.org/10.1126/sciadv.1602921",
    doi = "10.1126/sciadv.1602921",
    openalex = "W2797708712",
    references = "doi1010160012821x89900174, doi1010160016703790901288, doi1010160301926894000708, doi101016b0080437516030164, doi101016jpalaeo200611038, doi101016s001670379900126x, doi10103822941, doi101126science1097023, doi101126science1224126, doi101126science2765310235, doi101371journalpone0088987, doi104319lo1988334part20649"
}

Flood basalts were Earth's largest volcanic episodes that, along with related intrusions, were often emplaced rapidly and coincided with environmental disruption: oceanic anoxic events, hyperthermals, and mass extinction events. Volatile emissions, both from magmatic degassing and vaporized from surrounding rock, triggered short-term cooling and longer-term warming, ocean acidification, and deoxygenation. The magnitude of biological extinction varied considerably, from small events affecting only select groups to the largest extinction of the Phanerozoic, with less-active organisms and those with less-developed respiratory physiology faring especially poorly. The disparate environmental and biological outcomes of different flood basalt events may at first order be explained by variations in the rate of volatile release modulated by longer trends in ocean carbon cycle buffering and the composition of marine ecosystems. Assessing volatile release, environmental change, and biological extinction at finer temporal resolution should be a top priority to refine ancient hyperthermals as analogs for anthropogenic climate change. ▪ Flood basalts, the largest volcanic events in Earth history, triggered dramatic environmental changes on land and in the oceans. ▪ Rapid volcanic carbon emissions led to ocean warming, acidification, and deoxygenation that often caused widespread animal extinctions. ▪ Animal physiology played a key role in survival during flood basalt extinctions, with reef builders such as corals being especially vulnerable. ▪ The rate and duration of volcanic carbon emission controlled the type of environmental disruption and the severity of biological extinction.

@article{doi101146annurevearth053018060136,
    author = "Clapham, Matthew E. and Renne, Paul R.",
    title = "Flood Basalts and Mass Extinctions",
    year = "2019",
    journal = "Annual Review of Earth and Planetary Sciences",
    abstract = "Flood basalts were Earth's largest volcanic episodes that, along with related intrusions, were often emplaced rapidly and coincided with environmental disruption: oceanic anoxic events, hyperthermals, and mass extinction events. Volatile emissions, both from magmatic degassing and vaporized from surrounding rock, triggered short-term cooling and longer-term warming, ocean acidification, and deoxygenation. The magnitude of biological extinction varied considerably, from small events affecting only select groups to the largest extinction of the Phanerozoic, with less-active organisms and those with less-developed respiratory physiology faring especially poorly. The disparate environmental and biological outcomes of different flood basalt events may at first order be explained by variations in the rate of volatile release modulated by longer trends in ocean carbon cycle buffering and the composition of marine ecosystems. Assessing volatile release, environmental change, and biological extinction at finer temporal resolution should be a top priority to refine ancient hyperthermals as analogs for anthropogenic climate change. ▪ Flood basalts, the largest volcanic events in Earth history, triggered dramatic environmental changes on land and in the oceans. ▪ Rapid volcanic carbon emissions led to ocean warming, acidification, and deoxygenation that often caused widespread animal extinctions. ▪ Animal physiology played a key role in survival during flood basalt extinctions, with reef builders such as corals being especially vulnerable. ▪ The rate and duration of volcanic carbon emission controlled the type of environmental disruption and the severity of biological extinction.",
    url = "https://doi.org/10.1146/annurev-earth-053018-060136",
    doi = "10.1146/annurev-earth-053018-060136",
    openalex = "W2908782142",
    references = "doi1010160031018294903468, doi101016jgloplacha201105009, doi101038ncomms10825"
}

Interpretations of the tempo of mass extinctions and recoveries often rely on the distribution of fossils in a stratigraphic column. These interpretations are generally compromised when they are not based on a knowledge of marine ecological gradients and sequence-stratigraphic architecture. Crucially, last and first occurrences of species do not record times of extinction and origination. A face-value interpretation of the stratigraphic record leads to incorrect inferences of pulsed extinction, underestimates of the duration of mass extinction, and overestimates of local recovery times. An understanding of the processes of extinction and recovery is substantially improved by knowledge of the distribution of species along marine environmental gradients, interpreting sequence-stratigraphic architecture to show how those gradients are sampled through time, and sampling along regional transects along depositional dip. Doing so suggests that most ancient mass extinctions were substantially longer and local recoveries substantially shorter than generally thought. ▪ The concepts that let geologists find petroleum allow paleontologists to reinterpret ancient mass extinctions and their recoveries. ▪ Most ancient mass extinctions were longer than the fossil record suggests, lasting hundreds of thousands of years to a few million years. ▪ Ancient recoveries from mass extinctions were shorter than thought and likely overlapped with extinction during a period of turnover.

@article{doi101146annurevearth071719054827,
    author = "Holland, Steven M.",
    title = "The Stratigraphy of Mass Extinctions and Recoveries",
    year = "2019",
    journal = "Annual Review of Earth and Planetary Sciences",
    abstract = "Interpretations of the tempo of mass extinctions and recoveries often rely on the distribution of fossils in a stratigraphic column. These interpretations are generally compromised when they are not based on a knowledge of marine ecological gradients and sequence-stratigraphic architecture. Crucially, last and first occurrences of species do not record times of extinction and origination. A face-value interpretation of the stratigraphic record leads to incorrect inferences of pulsed extinction, underestimates of the duration of mass extinction, and overestimates of local recovery times. An understanding of the processes of extinction and recovery is substantially improved by knowledge of the distribution of species along marine environmental gradients, interpreting sequence-stratigraphic architecture to show how those gradients are sampled through time, and sampling along regional transects along depositional dip. Doing so suggests that most ancient mass extinctions were substantially longer and local recoveries substantially shorter than generally thought. ▪ The concepts that let geologists find petroleum allow paleontologists to reinterpret ancient mass extinctions and their recoveries. ▪ Most ancient mass extinctions were longer than the fossil record suggests, lasting hundreds of thousands of years to a few million years. ▪ Ancient recoveries from mass extinctions were shorter than thought and likely overlapped with extinction during a period of turnover.",
    url = "https://doi.org/10.1146/annurev-earth-071719-054827",
    doi = "10.1146/annurev-earth-071719-054827",
    openalex = "W2990917668",
    references = "doi101016jjseaes201702043, doi101017s0022336000024331"
}

Recent studies on mass extinctions are often based on the global fossil record, but data from selected paleogeographic regions under a relatively constant paleoenvironmental setting can also provide important information. Eighty-nine marine vertebrate species, including cartilaginous and bony fish and marine reptiles, from northern Gulf of Mexico - located about 500 km from the Chicxulub crater - offer a unique opportunity to determine an extinction process during the last 20 million years of the Late Cretaceous. Our diversity data show two separate extinction events: (i) the 'Middle Campanian Crisis' (about 77 Mya) and (ii) the end-Maastrichtian (66 Mya) events. Whether this stepwise pattern of extinctions occurred locally or globally cannot be determined at present due to the lack of a dataset of the marine vertebrate record for reliable comparison. However, this stepwise pattern including the Middle Campanian and end-Maastrichtian events for, at least, a 13 million-year interval indicates long-term global marine environmental changes (e.g., regression, ocean water chemistry change). Because most Cretaceous marine vertebrates already disappeared in the Gulf of Mexico prior to the latest Maastrichtian, the Chicxulub Impact may not be considered as the most devastating extinction event for the community.

@article{doi101038s4159802061089w,
    author = "Ikejiri, Takehito and Lu, YueHan and Zhang, Bo",
    title = "Two-step extinction of Late Cretaceous marine vertebrates in northern Gulf of Mexico prolonged biodiversity loss prior to the Chicxulub impact",
    year = "2020",
    journal = "Scientific Reports",
    abstract = "Recent studies on mass extinctions are often based on the global fossil record, but data from selected paleogeographic regions under a relatively constant paleoenvironmental setting can also provide important information. Eighty-nine marine vertebrate species, including cartilaginous and bony fish and marine reptiles, from northern Gulf of Mexico - located about 500 km from the Chicxulub crater - offer a unique opportunity to determine an extinction process during the last 20 million years of the Late Cretaceous. Our diversity data show two separate extinction events: (i) the 'Middle Campanian Crisis' (about 77 Mya) and (ii) the end-Maastrichtian (66 Mya) events. Whether this stepwise pattern of extinctions occurred locally or globally cannot be determined at present due to the lack of a dataset of the marine vertebrate record for reliable comparison. However, this stepwise pattern including the Middle Campanian and end-Maastrichtian events for, at least, a 13 million-year interval indicates long-term global marine environmental changes (e.g., regression, ocean water chemistry change). Because most Cretaceous marine vertebrates already disappeared in the Gulf of Mexico prior to the latest Maastrichtian, the Chicxulub Impact may not be considered as the most devastating extinction event for the community.",
    url = "https://doi.org/10.1038/s41598-020-61089-w",
    doi = "10.1038/s41598-020-61089-w",
    openalex = "W3009283096",
    references = "doi1026879266"
}

The ongoing sixth mass species extinction is the result of the destruction of component populations leading to eventual extirpation of entire species. Populations and species extinctions have severe implications for society through the degradation of ecosystem services. Here we assess the extinction crisis from a different perspective. We examine 29,400 species of terrestrial vertebrates, and determine which are on the brink of extinction because they have fewer than 1,000 individuals. There are 515 species on the brink (1.7% of the evaluated vertebrates). Around 94% of the populations of 77 mammal and bird species on the brink have been lost in the last century. Assuming all species on the brink have similar trends, more than 237,000 populations of those species have vanished since 1900. We conclude the human-caused sixth mass extinction is likely accelerating for several reasons. First, many of the species that have been driven to the brink will likely become extinct soon. Second, the distribution of those species highly coincides with hundreds of other endangered species, surviving in regions with high human impacts, suggesting ongoing regional biodiversity collapses. Third, close ecological interactions of species on the brink tend to move other species toward annihilation when they disappear-extinction breeds extinctions. Finally, human pressures on the biosphere are growing rapidly, and a recent example is the current coronavirus disease 2019 (Covid-19) pandemic, linked to wildlife trade. Our results reemphasize the extreme urgency of taking much-expanded worldwide actions to save wild species and humanity's crucial life-support systems from this existential threat.

@article{doi101073pnas1922686117,
    author = "Ceballos, Gerardo and Ehrlich, Paul R. and Raven, Peter H.",
    title = "Vertebrates on the brink as indicators of biological annihilation and the sixth mass extinction",
    year = "2020",
    journal = "Proceedings of the National Academy of Sciences",
    abstract = "The ongoing sixth mass species extinction is the result of the destruction of component populations leading to eventual extirpation of entire species. Populations and species extinctions have severe implications for society through the degradation of ecosystem services. Here we assess the extinction crisis from a different perspective. We examine 29,400 species of terrestrial vertebrates, and determine which are on the brink of extinction because they have fewer than 1,000 individuals. There are 515 species on the brink (1.7\% of the evaluated vertebrates). Around 94\% of the populations of 77 mammal and bird species on the brink have been lost in the last century. Assuming all species on the brink have similar trends, more than 237,000 populations of those species have vanished since 1900. We conclude the human-caused sixth mass extinction is likely accelerating for several reasons. First, many of the species that have been driven to the brink will likely become extinct soon. Second, the distribution of those species highly coincides with hundreds of other endangered species, surviving in regions with high human impacts, suggesting ongoing regional biodiversity collapses. Third, close ecological interactions of species on the brink tend to move other species toward annihilation when they disappear-extinction breeds extinctions. Finally, human pressures on the biosphere are growing rapidly, and a recent example is the current coronavirus disease 2019 (Covid-19) pandemic, linked to wildlife trade. Our results reemphasize the extreme urgency of taking much-expanded worldwide actions to save wild species and humanity's crucial life-support systems from this existential threat.",
    url = "https://doi.org/10.1073/pnas.1922686117",
    doi = "10.1073/pnas.1922686117",
    openalex = "W3030395860",
    references = "doi101007bf02763457, doi101016s0169534703000934, doi101073pnas1711842115, doi101093oso97801985491780010001, doi101126science21545391501, doi101126science2314734129, doi101126science7701342, doi1023073515466"
}

Mass extinction is characterized by the loss of 50 - 90 + percent of genetically and ecologically diverse species within 1 - 3.5 Myr intervals. Three conflicting theories exist: (1) Graded Mass Extinction; (2) Stepwise Mass Extinction; and (3) Catastrophic Mass Extinction. These can only be adequately tested with high resolution (cm-scale) stratigraphic data spanning the entire mass extinction interval and adjacent strata. Such data are presently available only for the Eocene-Oligocene (E-O), Cretaceous-Tertiary (K-T) and Cenomanian-Turonian (C-T) extinctions. In general, prevalent uniformitarian stratigraphic philosophy and use of the modern Earth/Life system as a model for the Phanerozoic has hindered the search for, and expectations of, high-resolution stratigraphic data critical) to mass extinction research. The modern Earth/Life "model" predicts highly variable, environmentally and biologically resilient systems and predominantly autocyclic stratigraphic response to large-scale forcing mechanisms.

@article{doi107203sjp25159,
    author = "Kauffman, Erle G.",
    title = "The dynamics of marine stepwise mass extinction",
    year = "2022",
    journal = "Spanish Journal of Palaeontology",
    abstract = {Mass extinction is characterized by the loss of 50 - 90 + percent of genetically and ecologically diverse species within 1 - 3.5 Myr intervals. Three conflicting theories exist: (1) Graded Mass Extinction; (2) Stepwise Mass Extinction; and (3) Catastrophic Mass Extinction. These can only be adequately tested with high resolution (cm-scale) stratigraphic data spanning the entire mass extinction interval and adjacent strata. Such data are presently available only for the Eocene-Oligocene (E-O), Cretaceous-Tertiary (K-T) and Cenomanian-Turonian (C-T) extinctions. In general, prevalent uniformitarian stratigraphic philosophy and use of the modern Earth/Life system as a model for the Phanerozoic has hindered the search for, and expectations of, high-resolution stratigraphic data critical) to mass extinction research. The modern Earth/Life "model" predicts highly variable, environmentally and biologically resilient systems and predominantly autocyclic stratigraphic response to large-scale forcing mechanisms.},
    url = "https://doi.org/10.7203/sjp.25159",
    doi = "10.7203/sjp.25159",
    openalex = "W4294609470"
}