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Testable examples of the emergence and development of novelty from evolution

Post of the Month: June 2008


Subject:    | Can Steven J produce the testable details concerning emergence of novelty and its development?
Date:       | 29 Jun 2008
Message-ID: |

Steven J. wrote:
>> No, Tony, the point of evolutionary theory is that it is possible to
>> go into a great deal more detail than "nature did it," with testable
>> predictions about *how* "nature did it."

Tony Pagano wrote:
> 1. Nonsense. Random mutations coupled to natural selection explains
> only a very narrow range of observations. That is, it explains minor
> variations---back and forth---within (admittedly) fuzzy limits of
> EXISTING characteristics.

You post this shortly after reports of how _E. coli_ in the lab has evolved the ability to metabolize citrate, an ability hitherto unknown among this strain. You post it weeks after reports of how Italian wall lizards, transplanted to a new island home on Pod Mrcaru, evolved cecal valves in their digestive tracts (again, a trait previously unknown in this species). You post it, on the other hand, years after reports of how random mutation coupled with natural selection have produced bacteria able to digest nylon, or to resist -- or even feed upon -- antibiotics unknown in nature. There is NO reason, empirical or theoretical (as opposed to theological) to suppose that mutation and natural selection can alter a population "only [within] a very narrow range." Even Michael Behe's (demonstrably flawed) argument in _The Edge of Evolution_ only proscribes certain types of transformations, with no indication that, e.g. the changes needed to produce lemurs and humans from a common ancestor require any sequence of mutations that Behe finds problematical.

Oh, and strictly speaking, "nonsense" implies that my assertion is not merely wrong, but self-contradictory or otherwise absurd on its face. I think you should stick with the more modest "you err."

> 2. Secularists don't have a clue how novelty emerges or how it
> progresses to maturity. Such events have NEVER been observed---NEVER.

Since you've never defined this quality "novelty," it's not clear what would qualify as observing it, or as an explanation for it. However, one can have a pretty good idea of how something happens without observing it directly (and conversely, one can observe a thing and have no clue how it is possible). In evolution, "novel" features (as most people define the term) emerge as modifications of previously existing features, or as modifications of duplications of previously existing features.

> 3. The fossil record does not show the ubiquitous transformism that
> neoDarwinism predicted. It shows without exception "sudden
> appearance" and "STASIS."

The last time we had this discussion, it was painfully clear that you did not know what "stasis" meant (Gould and Eldredge used the term to indicate that, at least at the morphological level, a species had undergone no evolution at all; you use it to describe entire sequences of similar but clearly distinct species each showing microevolutionary changes as they transition from one to another). Someone who talks about the Pearson, _et al._ foram sequence as showing "stasis" is just using words as magic charms, not to convey meaning or express understanding.

Note that many of what you seem to regard as "novelties" (e.g. bird bills, bird wings, and feathers) do not appear full-blown and without precursors in the fossil record: one can trace intermediate forms in various maniraptoran theropods. Usually *species*, even entire genera, appear without clear precursors, but speciation has been observed in the lab (i.e. the sort of change that is worst-documented in the fossil record is precisely the kind that has been observed in the present day among living populations), and the fossil record is known to be incomplete and incompletely uncovered and described.

Note, by the way, that Darwin himself suggested that a typical lineage would spend far more time NOT evolving (i.e. in stasis) than it did changing. Ernst Mayr, one of the founders of modern "neo-Darwinism," expanded on this idea, laying the theoretical groundwork for "punctuated equilibria," the idea that stasis was the normal state of species and populations, and that evolution took place not slowly over an entire species but relatively rapidly in isolated populations of the species. So it would seem that "neoDarwinism" does not necessarily predict "ubiquitous transformism" in the fossil record.

> 4. Genetics/Population Genetics have not found any observable
> mechanisms that would progressively and coherently incorporate only
> beneficial mutations while discarding all the unhelpful ones. All of
> the known mechanisms either shuffle existing information or
> dramatically attenuate all mutations. Populations in the wild tend
> toward stasis not ubiquitous change.

If by "unhelpful," you mean "selectively neutral," there is neither need nor reason to suppose that they are routinely discarded. If by "unhelpful," you mean "harmful," the observable mechanism is called "death before reproducing." Again, you're using words as though they were magical incantations, that achieved affects even though neither you nor your audience know their meaning. Selective breeding does exactly what you describe: progressively incorporate beneficial ("beneficial" depending on the selective criteria) mutations while discarding harmful ones. Natural selection -- differential survival of variants in an environment without intelligent intervention -- accomplishes the same thing, although generally much more slowly. Since mutations occur constantly, new variation appears to replace variation that has been lost due to natural selection. Note that in a stable environment, populations will already tend to be well-adapted, and will be experiencing stabilizing rather than transformative selection.

> 5. One of the founders of population genetics (J.B.S. Haldane)
> outlined a serious UNSOLVED problem----the cost of substitution when a
> beneficial mutation occurs. This is another dramatic attenuator of
> any change.

Haldane's dilemma makes a number of assumptions: that evolution takes place in populations that are already well-suited to their environment (i.e. the opposite assumption of punctuated equilibrium), that all genetic changes are adaptive (i.e. the opposite assumption of Kimura's theory that most evolutionary change, at the genetic level, is neutral drift), and various other technical assumptions that are also questionable in many circumstances. ReMine argued that Haldane's calculations limited the number of beneficial mutations fixed since the human-chimp last common ancestor to no more than 1,000, and blithely regarded this as a disproof of evolution, without bothering to even assert (much less provide evidence) that in fact there were even 1,000 (much less a larger number) of adaptive differences between the human and chimpanzee genome. So it is not clear why Haldane's dilemma should be any sort of a problem for an evolutionary explanation of biological diversity and complexity.

> 6. Natural Selection is a misleading misnomer. It is a term that
> refers to "differential survival" in the wild. It is a stochastic
> process; which is to say that there are so many variables in the wild
> that it is no easier to predict which individuals in a population will
> survive than it is to predict the weather. What is "beneficial" is
> entirely situational. Populations already express a healthy variation
> within its individuals so that it collectively survives in the varied
> conditions with which it is faced.

Again, do you even understand the argument(s) you are presenting here? To say that variables are so numerous that prediction is difficult means that a process is "chaotic," not "stochastic;" our inability to predict the outcome of a complex situation does not mean that the situation is not largely, or even entirely, deterministic. To say that what is "beneficial" is entirely situational is [a] to tell me what I've told you on many occasions, and [b] to explain why the same process can produce such diverse outcomes in nature. And the point of a "healthy variation" is that some variants *don't* survive in various environments; their variations are lost (and replaced by similar or different variants by later mutations). So you've constructed an argument that evolution must occur, and used it as an argument that evolution cannot occur.

> 7. Abiogenesis is completely failed and stagnated.

Have you looked into the recent researches of Jack Szostak? Abiogenesis research has been exploring a number of new (and new versions of old) ideas in recent years. In any case, how the first prokaryotes originated has very little bearing on the evidence that you share common ancestry with gorillas and ginkos, and whether any particular theory of abiogenesis holds water has very little to do with whether mutation and natural selection can modify existing structures in living things to produce "evolutionary novelties."

> 8. Finally Niles Eldredge has made clear over the years that
> evolutionists not only DON'T know what causes novelty to emerge and
> develop to maturity there is no consensus on the conception among
> secularists. There are at least two major belief systems: the
> Dawkinsian gradualists and the Gouldian Punc Eqers. And there is a
> small

Again, you do not support your argument by repeatedly demonstrating that you do not know what you're talking about. Phyletic gradualism and punctuated equilibrium are different ideas about the tempo and mode of evolution: whether species change constantly at a slower-than-glacial pace, across their entire range, or whether evolution takes place over centuries rather than millions of years in small areas. It's not an argument over natural selection vs. some other mechanism for adaptive change ("what causes novelty to emerge"). How fast and how regularly a cause operates is not the same thing as what the cause actually is.

> But I'll call Steven J's bluff...please produce the EMPIRICALLY
> testable details which show how novelty emerged in prehistory (and
> should be emerging now), how novel structures progressed to maturity
> in prehistory, and how this process overcomes all the attentuating
> factors including Haldane's Dilemma. To save time for you a link to a
> peer reviewed journal would suffice.

Let's see ... you don't know what you mean by "novelty" (neither do I, but since you don't know, it won't do me any good to ask you), you don't seem to understand that evolutionary change is supposed to be contingent, not moving towards some predestined "maturity," you don't know what Haldane's Dilemma is or what problems it really poses (and granted, again, I'm no expert on the matter). So your question is well-nigh meaningless, and any attempt to answer it (or some more sensible set of questions in its place) would be beyond your comprehension. So I shall not link to Lenski's _E. coli_ paper recently published.

It is very difficult (for reasons you yourself, in your sole more or less literate paragraph, have detailed) to say what selection pressures operated in the prehistoric past, or whether the transformation from theropod forelimb to bird's wing was driven purely by natural selection or by some other sort of cause (e.g. "structuralist" internal tendencies dictated by embryonic development and physical constraints). One can, of course, test to see whether natural selection operates in the present, or whether it can produce traits that strike people as "novel" when they actually have some testable concept of "novelty." My original point, of course, was that one can much more easily test the whole idea that species are, in fact, related by common descent, and test hypotheses about phylogeny and about which structures were modified, in what ways, to produce "novel" features. So I think you have misidentified my "bluff."

But thank you for responding.

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