No new species have been observed.
- New species have arisen in historical times. For example:
- A new species of mosquito, isolated in London's
Underground, has speciated from Culex pipiens (Byrne and Nichols
1999; Nuttall 1998).
- Helacyton gartleri is the HeLa cell culture, which evolved from a
human cervical carcinoma in 1951. The culture grows indefinitely and
has become widespread (Van Valen and Maiorana 1991).
A similar event appears to have happened with dogs relatively
recently. Sticker's sarcoma, or canine transmissible venereal tumor,
is caused by an organism genetically independent from its hosts but
derived from a wolf or dog tumor (Zimmer 2006; Murgia et al. 2006).
- Several new species of plants have arisen via polyploidy (when the
chromosome count multiplies by two or more) (de Wet 1971). One
example is Primula kewensis (Newton and Pellew 1929).
- Incipient speciation, where two subspecies interbreed rarely or with
only little success, is common. Here are just a few examples:
- Rhagoletis pomonella, the apple maggot fly, is undergoing sympatric
speciation. Its native host in North America is Hawthorn
spp.), but in the mid-1800s, a new population formed on introduced
domestic apples (Malus pumila). The two races are kept partially
isolated by natural selection (Filchak et al. 2000).
- The mosquito Anopheles gambiae shows incipient speciation between
its populations in northwestern and southeastern Africa (Fanello et
al. 2003; Lehmann et al. 2003).
- Silverside fish show incipient speciation between marine and
estuarine populations (Beheregaray and Sunnucks 2001).
- Ring species show the process of speciation in action. In ring
species, the species is distributed more or less in a line, such as
around the base of a mountain range. Each population is able to breed
with its neighboring population, but the populations at the two ends
are not able to interbreed. (In a true ring species, those two end
populations are adjacent to each other, completing the ring.) Examples
of ring species are
- the salamander Ensatina, with seven different subspecies on the
west coast of the United States. They form a ring around
California's central valley. At the south end, adjacent subspecies
klauberi and eschscholtzi do not interbreed (Brown n.d.;
- greenish warblers (Phylloscopus trochiloides), around the
Himalayas. Their behavioral and genetic characteristics change
gradually, starting from central Siberia, extending around the
Himalayas, and back again, so two forms of the songbird coexist but
do not interbreed in that part of their range (Irwin et al. 2001;
Whitehouse 2001; Irwin et al. 2005).
- the deer mouse (Peromyces maniculatus), with over fifty subspecies
in North America.
- many species of birds, including Parus major and P. minor,
Halcyon chloris, Zosterops, Lalage, Pernis,
argentatus group, and Phylloscopus trochiloides (Mayr 1942,
- the American bee Hoplitis (Alcidamea) producta (Mayr 1963, 510).
- the subterranean mole rat, Spalax ehrenbergi (Nevo 1999).
- Evidence of speciation occurs in the form of organisms that exist only
in environments that did not exist a few hundreds or thousands of years
ago. For example:
- In several Canadian lakes, which originated in the last 10,000
years following the last ice age, stickleback fish have diversified
into separate species for shallow and deep water (Schilthuizen
- Cichlids in Lake Malawi and Lake Victoria have diversified into
hundreds of species. Parts of Lake Malawi which originated in the
nineteenth century have species indigenous to those parts
(Schilthuizen 2001, 166-176).
- A Mimulus species adapted for soils high in copper exists only on
the tailings of a copper mine that did not exist before 1859
There is further evidence that speciation can be caused by infection
with a symbiont. A Wolbachia bacterium infects and causes
reproductive isolation between the wasps Nasonia vitripennis and
N. giraulti (Bordenstein and Werren 1997).
- Some young-earth creationists claim that speciation is essential to
explain Noah's ark. The ark was not roomy enough to carry and care for
all species, so speciation is invoked to explain how the much fewer
"kinds" aboard the ark became the diversity we see today. Also, some
species have special needs that could not have been met during the
flood (e.g., fish requiring fresh water). Creationists assume that
they evolved from other, more tolerant organisms since the Flood.
Kimball, John W., 2003. Speciation.
Stassen, C. et al., 1997. Some more observed speciation events.
- Beheregaray, L. B. and P. Sunnucks, 2001. Fine-scale genetic
structure, estuarine colonization and incipient speciation in the
marine silverside fish Odontesthes argentinensis. Molecular
Ecology 10(12): 2849-2866.
- Bordenstein, Seth R. and John H. Werren. 1997. Effection of An and B
Wolbachia and host genotype on interspecies cytoplasmic incompatibility
in Nasonia. Genetics 148: 1833-1844.
- Brown, Charles W., n.d. Ensatina eschscholtzi Speciation in
progress: A classic example of Darwinian evolution.
- Byrne, K. and R. A. Nichols, 1999. Culex pipiens in London
Underground tunnels: differentiation between surface and subterranean
populations. Heredity 82: 7-15.
- de Wet, J. M. J., 1971. Polyploidy and evolution in plants. Taxon
- Fanello, C. et al., 2003. The pyrethroid knock-down
resistance gene in the Anopheles gambiae complex in Mali and further
indication of incipient speciation within An. gambiae s.s.
Molecular Biology 12(3): 241-245.
- Filchak, Kenneth E., Joseph B. Roethele and Jeffrey L. Feder, 2000.
Natural selection and sympatric divergence in the apple maggot
Rhagoletis pomonella. Nature 407: 739-742.
- Irwin, Darren E., Staffan Bensch and Trevor D. Price, 2001. Speciation
in a ring. Nature 409: 333-337.
- Irwin, Darren E., Staffan Bensch, Jessica H. Irwin and Trevor D.
Price. 2005. Speciation by distance in a ring species. Science
- Lehmann, T., M. Licht, N. Elissa, et al., 2003. Population structure
of Anopheles gambiae in Africa. Journal of Heredity 94(2):
- Macnair, M. R., 1989. A new species of Mimulus endemic to copper
mines in California. Botanical Journal of the Linnean
Society 100: 1-14.
- Mayr, E., 1942. Systematics and the Origin of Species. New York:
Columbia University Press.
- Mayr, E., 1963. Animal Species and Evolution. Cambridge, MA:
- Murgia, Claudio et al. 2006. Clonal origin and evolution of a
transmissible cancer. Cell 126: 477-487.
- Nevo, Eviatar, 1999. Mosaic Evolution of Subterranean Mammals:
Regression, Progression and Global Convergence. Oxford University
- Newton, W. C. F. and Caroline Pellew, 1929. Primula kewensis and its
derivatives. Journal of Genetics 20(3): 405-467.
- Nuttall, Nick, 1998. Stand clear of the Tube's 100-year-old super-bug.
Times (London), 26 Aug. 1998, 1.
- Schilthuizen, M., 2001. (see below)
- Van Valen, Leigh M. and Virginia C. Maiorana, 1991. HeLa, a new
microbial species. Evolutionary Theory 10: 71-74.
- Wake, David B., 1997. Incipient species formation in salamanders of
the Ensatina complex. Proceedings of the National Academy of
Science USA 94: 7761-7767.
- Whitehouse, David, 2001. Songbird shows how evolution works.
BBC News Online, 18 Jan. 2001,
- Woodmorappe, John, 1996. Noah's Ark: A Feasability Study, El
Cajon, CA: ICR.
- Zimmer, Carl. 2006. A dead dog lives on (inside new dogs).
Callaghan, Catherine A., 1987. Instances of observed speciation. The
American Biology Teacher 49: 34-36.
Schilthuizen, Menno., 2001. Frogs, Flies, and Dandelions: the Making of
Species, Oxford Univ. Press, esp. chap. 1.
created 2001-3-31, modified 2006-9-7