Sunday, March 11, 2007

`Our confidence in the fact of evolution rests upon copious data that fall, roughly, into three great classes' (Gould) #1

AN

Thanks for your message and my apologies for the long delay in responding.

[Above: Evolution at different scales: micro to macro, Berkeley University]

As is my normal practice, I am replying to it via my blog CED, minus your personal identifying information.

----- Original Message -----
From: AN
To: Stephen E. Jones
Sent: Monday, February 26, 2007 6:26 AM
Subject: Gould

>Hi Steve. Can you help me with a question? Darwinians quite often discount microevolution to explain macroevolution.

I am not sure what you mean by this. The true Darwinian position is that "all evolution is due to the accumulation of small genetic changes, guided by natural selection" and therefore "transpecific evolution"( i.e. macroevolution) "is nothing but an extrapolation and magnification of the events that take place within populations and species" (i.e. microevolution):

"The proponents of the synthetic theory maintain that all evolution is due to the accumulation of small genetic changes, guided by natural selection, and that transpecific evolution is nothing but an extrapolation and magnification of the events that take place within populations and species." (Mayr, E.W., "Populations, Species and Evolution," [1970], Harvard University Press: Cambridge MA, Reprinted, 1974, p.351)

That Darwinism has not really changed in its insistence that macroevolution is really just microevolution write large, i.e. "flies in bottles ... extended":

"Geneticists can study the gradual increase of favored genes within populations of fruit flies in laboratory bottles. Naturalists can record the steady replacement of light moths by dark moths as industrial soot blackens the trees of Britain. Orthodox neo-Darwinians extrapolate these even and continuous changes to the most profound structural transitions in the history of life: by a long series of insensibly graded intermediate steps, birds are linked to reptiles, fish with jaws to their jawless ancestors. Macroevolution (major structural transition) is nothing more than microevolution (flies in bottles) extended. If black moths can displace white ones in a century, then reptiles can become birds in a few million years by the smooth and sequential summation of countless changes. Change of gene frequencies in local populations is an adequate model for all evolutionary processes-or so the current orthodoxy states." (Gould, S.J., "The Return of Hopeful Monsters," Natural History, Vol. 86, No. 6, June-July 1977, pp.23-30, p.23)

is evident from this quote at Berkeley University's Understanding Evolution website that "Despite their differences" (i.e. "micro- and macroevolution") "evolution at both of these levels relies on the same, established mechanisms of evolutionary change" (my emphasis) :

"Evolution encompasses changes of vastly different scales - from something as insignificant as an increase in the frequency of the gene for dark wings in beetles from one generation to the next, to something as grand as the evolution and radiation of the dinosaur lineage. These two extremes represent classic examples of micro- and macroevolution. Microevolution happens on a small scale (within a single population), while macroevolution happens on a scale that transcends the boundaries of a single species. Despite their differences, evolution at both of these levels relies on the same, established mechanisms of evolutionary change." ("Evolution at different scales: micro to macro," Understanding Evolution, University of California, Berkeley)

>but when the heat is on Darwinism, the same critcs (Gould, Eldredge) appear to make a retreat to the extrapolationist view.

Indeed! The classic example was the late Stephen Jay Gould who from the 1970's had adopted "the critical stance that had made him famous-that gradualistic neo-Darwinism was incapable of accounting for the rarity of transitional fossils" yet in a 1989 private debate with Phillip E. Johnson, "Gould argued that there is plenty of scientific evidence in the fossil record for Darwinian evolution and cited a number of fossil series that allegedly supported the validity of step-by-step Darwinian macroevolution":

"Gould vs. Johnson: The Campion Debate Just fourteen months after the [1988] Berkeley colloquium, Phillip Johnson's plane began its descent into Logan Airport in Boston, carrying him on a collision course with Stephen Jay Gould. In a matter of hours Johnson would be meeting the prestigious Harvard evolutionist for the first time at a private gathering of experts called together to discuss the problem of `Science and Creationism in Public Schools.' ... What he did not quite expect was the ferocious attack and intense duel that would break out. Gould had already established his reputation as one of the twentieth century's most prolific masters of scientific prose and was undoubtedly America's most popular and widely read spokesperson for evolution. ... On Saturday morning as the participants were gathering for the second session, Johnson and Gould met briefly. Their chat was polite, but Gould signaled to Johnson that, having read the material shipped from Berkeley, his response to Johnson was going to be an urgent polemic. He told Johnson, `You're a creationist, and I've got to stop you.' As the morning session got underway, Johnson was first given an opportunity to summarize the gist of his Berkeley paper and the much shorter `Campion Summary.' For over an hour Johnson reviewed point after point of his thesis. Near the end of his presentation, paleontologist David Raup briefly interjected his own evaluation of Johnson's work. He said that he had read the Berkeley paper and had even distributed it and discussed it with his students in one of his graduate seminars at the University of Chicago. Raup said he and his students agreed that Johnson's scholarship was fully accurate in its scientific detail and contained a clear understanding of macroevolution's anomalies and empirical gaps. In fact, said Raup, the various lines of evidence for Darwinian macroevolution were not nearly as strong as one would hope. The key point was clear-Raup had briefly but unmistakably certified the empirical quality of Johnson's critique. At this point, Gould immediately seized the floor and `donned the mantle of Darwin.' Displaying agitation in voice and shaking bodily, he began to set the record straight. In what one observer described as an `obliteration attack,' Gould started pelting Johnson's thesis with vehement criticisms. Oddly, Gould argued that there is plenty of scientific evidence in the fossil record for Darwinian evolution and cited a number of fossil series that allegedly supported the validity of step-by-step Darwinian macroevolution. On this point, Gould was clearly backing away from the critical stance that had made him famous-that gradualistic neo-Darwinism was incapable of accounting for the rarity of transitional fossils. On the contrary Gould implied that the branches of evolutionary trees could be reasonably traced in the fossil record. Very early in the attack, Johnson stepped in with strong rebuttals of a number of Gould's points, and immediately the two were engaged in a furiously paced seesaw debate that lasted for nearly an hour before a spellbound audience. The rhetorical purpose of Gould was clear-to so bury Johnson's criticism in a torrent of contrary evidence that the net effect would be to illegitimize both the logos and ethos of Johnson's critique while defending classic neo-Darwinism. However ... many felt the emotional intensity of Gould's all-out attack clashed with the spirit of the meeting and somewhat undermined his credibility. ... In the final analysis, many who attended described the private debate as a draw." (Woodward, T.E., "Doubts about Darwin: A History of Intelligent Design," Baker: Grand Rapids MI, 2003, pp.79,82-83. Emphasis original)

>For example, when Gould answered Kristol in Discover magazine in his article called "Darwinism Defined" he spoke about microevolution as establishing evolution as a fact.

Agreed. Gould in that article, despite his earlier derision about "Orthodox neo-Darwinians" who "extrapolate these even and continuous changes to the most profound structural transitions in the history of life" so that "Macroevolution (major structural transition) is nothing more than microevolution (flies in bottles) extended", gave as his first line of evidence for "the fact of evolution" the "direct evidence of small-scale changes in controlled laboratory experiments ... on bacteria ... the fruit fly Drosophila ... or observed in nature ... color changes in moth wings" etc "or produced" by "human breeding and agriculture":

"Our confidence in the fact of evolution rests upon copious data that fall, roughly, into three great classes. First, we have the direct evidence of small-scale changes in controlled laboratory experiments of the past hundred years (on bacteria, on almost every measurable property of the fruit fly Drosophila), or observed in nature (color changes in moth wings, development of metal tolerance in plants growing near industrial waste heaps), or produced during a few thousand years of human breeding and agriculture. Creationists can scarcely ignore this evidence, so they respond by arguing that God permits limited modification within created types, but that you can never change a cat into a dog (who ever said that you could, or that nature did?)." (Gould, S.J., "Darwinism Defined: The Difference Between Fact and Theory," Discover, January 1987, pp.64-70, pp.65,68)

But then he admits that "Creationists" accept "this evidence" and argue that "God permits limited modification within created types". So how can that then be evidence for "the fact of evolution" if even creationists accept it?

>Am I reading Gould Correctly? Is he saying that this small changes add up to big ones?

Gould was deliberately ambiguous on this point. In one breath Gould claimed that microevolutionary "shortest-term studies are elegant and important" yet in the other he dismissed such "Evolutionary rates of a moment, as measured for guppies and lizards, are vastly too rapid to represent the general modes of change that build life's history through geological ages":

"These shortest-term studies are elegant and important, but they cannot represent the general mode for building patterns in the history of life. The reason strikes most people as deeply paradoxical, even funny-but the argument truly cannot be gainsaid. Evolutionary rates of a moment, as measured for guppies and lizards, are vastly too rapid to represent the general modes of change that build life's history through geological ages. ... These measured changes over years and decades are too fast by several orders of magnitude to build the history of life by simple cumulation. Reznick's guppy rates range from 3,700 to 45,000 darwins (a standard metric for evolution, expressed as change in units of standard deviation-a measure of variation around the mean value of a trait in a population-per million years). By contrast, rates for major trends in the fossil record generally range from 0.1 to 1.0 darwins. Reznick himself states that `the estimated rates [for guppies] are...four to seven orders of magnitude greater than those observed in the fossil record' (that is, ten thousand to ten million times faster!)." (Gould, S.J., "The Paradox of the Visibly Irrelevant," Natural History, December 1997/January 1998, Vol. 106, No. 11, pp.61-62,64)

But if "These shortest-term studies ... cannot represent the general mode for building patterns in the history of life" then in what sense are they "important"? Gould's own article title says that they are "Irrelevant"!

Then again, Gould did write at the outset of his 1987 Discover article that "evolution (as theory) is indeed `a conglomerate idea consisting of conflicting hypotheses" (my emphasis)!:

"Well, Mr. Kristol, evolution (as theory) is indeed `a conglomerate idea consisting of conflicting hypotheses,' and I and my colleagues teach it as such." (Gould, S.J., "Darwinism Defined: The Difference Between Fact and Theory," Discover, January 1987, pp.64-70, p., p.65).

His real problem is that despite his (and his fellow paleontologists) failure to find confirming evidence in the fossil record for the natural selection of random mutations being a major factor in macroevolution, in the end he had to admit that naturalistically he had nothing better to offer "than natural selection" of random mutations "to build structures of such eminently workable design":

"Since the ultras [ultra-Darwinists] are fundamentalists at heart, and since fundamentalists generally try to stigmatize their opponents by depicting them as apostates from the one true way, may I state for the record that I (along with all other Darwinian pluralists) do not deny either the existence and central importance of adaptation, or the production of adaptation by natural selection. Yes, eyes are for seeing and feet are for moving. And, yes again, I know of no scientific mechanism other than natural selection with the proven power to build structures of such eminently workable design." (Gould, S.J., "Darwinian Fundamentalism," The New York Review of Books, June 12, 1997. Parenthesis mine).

>Or is he merely knocking down a straw man by saying that creationists can't account for any kind of change. Thanks

I do indeed maintain that Gould is "knocking down a straw man by saying that creationists can't account for any kind of change." That is, in the sense that Gould's straw man is confusing "creationism" with those versions of creationism that reject Universal Common Ancestry (e.g. Young-Earth Creationism and the more popular version of Old-Earth Creationism and Progressive Creationism).

Indeed, as I will argue in a further part #2 and perhaps a part #3 of this post, Gould's second and third of his "three great classes" of evidence on which his "confidence in the fact of evolution rests," while they may count against those versions of creationism above that do not accept Universal Common Ancestry, they fail to uniquely establish evolution against those versions of creationism that do accept Universal Common Ancestry (as I do), e.g. my Progressive Mediate Creation position.

>AN

Stephen E. Jones, BSc. (Biology).


Exodus 8:16-19. 16Then the LORD said to Moses, "Tell Aaron, 'Stretch out your staff and strike the dust of the ground,' and throughout the land of Egypt the dust will become gnats." 17They did this, and when Aaron stretched out his hand with the staff and struck the dust of the ground, gnats came upon men and animals. All the dust throughout the land of Egypt became gnats. 18But when the magicians tried to produce gnats by their secret arts, they could not. And the gnats were on men and animals. 19The magicians said to Pharaoh, "This is the finger of God." But Pharaoh's heart was hard and he would not listen, just as the LORD had said.

2 comments:

Unguided said...

My understanding was that there are quite a few good examples of multiple microevolution changes adding up to create a change of species. From memory documented examples include mosquitoes and amoeba. Extrapolating to the fossil record something scientists have witnessed now is not an unreasonable position to take.

Also I think you are creating a bit of a straw man yourself. Scientists would reject microevolutiontiary changes leading to macro ones if there was evidence to show this was not the case. My understanding of ID and creationism is that there is no credible counter argument that provides evidence that microevolution cannot result in macro changes. Most ID proponents suggest that something could have evolved or it could have been designed. Most scientists then accept the evidence mentioned above that shows it is happening, than the "but it looks designed to me" approach to determine which theory they prefer.

Stephen E. Jones said...

Unguided

Thanks for reminding me that I have not completed this planned 3-part post!

>My understanding was that there are quite a few good examples of multiple microevolution changes adding up to create a change of species.

Since the classic definition of a "species" is "groups of actually or potentially interbreeding natural populations, which are reproductively isolated from other such groups":

"A practical species definition, and this is after all what the taxonomist wants for his work, will have to compromise by combining the criteria of several species concepts. I have recently (Mayr 1940a [Mayr, E., "Speciation phenomena in birds," American Naturalist, Vol. 74, May-June, 1940, pp.249-278]) proposed the following formulation: `A species consists of a group of populations which replace each other geographically or ecologically and of which the neighboring ones intergrade or interbreed wherever they are in contact or which are potentially capable of doing so (with one or more of the populations) in those cases where contact is prevented by geographical or ecological barriers.' Or shorter: `Species are groups of actually or potentially interbreeding natural populations, which are reproductively isolated from other such groups.'" (Mayr, E.W., "Systematics and the Origin of Species," [1942], Columbia University Press: New York NY, Reprinted, 1982, p.120).

two outwardly identical populations of fruitfly that have adapted to the different ripening times of different fruits (e.g. Rhagoletis pomonella):

"Organisms that remain within the same physical area may nevertheless become isolated through adaptations to fit slightly different ecological niches. This may be seen particularly in insects. The life-cycle of an insect is generally short and several generations can succeed one another within a single year. A change in the environment can thus produce rapid consequences. A North American fruit fly (Rhagoletis pomonella) has divided into two populations that depend on different trees in the same area. One lives on hawthorns and the other on apple trees, and the two populations do not cross-breed. How did this happen? Two centuries ago, there were only hawthorn flies. The females laid their eggs in August on the hawthorns and at the end of September the larvae fed on the red fruits. Later, apple trees were introduced into the area. There is enough genetic variability among fruit flies that the population gave rise to some individuals that reproduced a month early. These flies now found apple trees on which to lay their eggs, and the resulting larvae fed on apples, which ripen earlier than hawthorn fruit. A new population, dependent on the apple tree, thus became established. Because of the one-month difference in their mating schedules, the two flies do not mate in the wild. Since gene exchange no longer occurs, the two populations may eventually develop into separate species. Yet they look exactly alike and are still capable of mating in the laboratory." (Davis, P. & Kenyon, D.H., "Of Pandas and People: The Central Question of Biological Origins", Foundation for Thought and Ethics: Richardson TX, Second Edition, 1993, pp.17-18)

would be regarded as two different "species" (note "potentially" in Mayr's definition). And indeed, my genetics textbook gives Rhagoletis pomonella as "An example of incipient sympatric speciation":

"In sympatric speciation, reproductive speciation process isolation evolves while the incipient group is still in the vicinity of the parent population. An example of incipient sympatric speciation has been seen recently in host races of the apple maggot fly (Rhagoletis pomonella) in North America ... . This fly was found originally only on hawthorn plants. However, in the nineteenth century, it spread as a pest to newly introduced apple trees. In fact, races are now known on pear and cherry trees and on rose bushes. These races have developed genetic, behavioral, and ecological differences from the original hawthorn-dwelling parent. Evolutionary biologists view this as an opportunity to observe sympatric speciation as it occurs." (Tamarin, R.H., "Principles of Genetics," International Edition, [1996], McGraw-Hill: New York NY, Seventh Edition, 2002, p.593)

Therefore, with the bar of "species" set so low, presumably not even the strictest Young-Earth Creationist would deny that "multiple microevolution changes" could "add... up to create a change of species."

It is: 1) macroevolution, in the sense of change from one major taxonomic category to another, e.g. from reptiles (Class Reptilia) to birds (Class Aves); by 2) nothing but the Darwinian cumulative selection of random micromutations, that is at issue.

>From memory documented examples include mosquitoes and amoeba.

See above. Presumably this is just from "mosquitoes" to "mosquitoes" and "amoeba" to "amoeba"? Now if Darwinism could explain the transition from "amoeba" to "mosquitoes", by nothing but the cumulative selection of random micromutations, that would be interesting.

Indeed, Darwinists continuing to give such trivial examples, such as "mosquitoes" to "mosquitoes" and "amoeba" to "amoeba" shows that they have nothing better.

>Extrapolating to the fossil record something scientists have witnessed now is not an unreasonable position to take.

That might be so if "the fossil record" actually documented microevolutionary change accumulating into macroevolutionary change. But it doesn't. The paleontologist Steven Stanley in his book on macroevolution, points out that:

"The known fossil record fails to document a single example of phyletic evolution accomplishing a major morphologic transition and hence offers no evidence that the gradualistic model can be valid." (Stanley, S.M., "Macroevolution: Pattern and Process," [1979], The Johns Hopkins University Press: Baltimore MD, Reprinted, 1998, p.39)

>Also I think you are creating a bit of a straw man yourself. Scientists would reject microevolutiontiary changes leading to macro ones if there was evidence to show this was not the case.

They have - over a quarter of a century ago:

"The changes within a population have been termed microevolution, and they can indeed be accepted as a consequence of shifting gene frequencies. Changes above the species level-involving the origin of new species and the establishment of higher taxonomic patterns- are known as macroevolution. The central question of the Chicago conference was whether the mechanisms underlying microevolution can be extrapolated to explain the phenomena of macroevolution. At the risk of doing violence to the positions of some of the people at the meeting, the answer can be given as a clear, No." (Lewin, R., "Evolutionary- Theory Under Fire: An historic conference in Chicago challenges the four-decade long dominance of the Modern Synthesis," Science, Vol. 210, pp.883-887, 21 November 1980, p.883)

>My understanding of ID and creationism is that there is no credible counter argument that provides evidence that microevolution cannot result in macro changes.

First, "ID and creationism" are two very different things.

Second, if that is your "understanding," then you sound like you are a typical Internet evolutionist who knows very little about evolution, let alone creationism or ID. If so, then from over a decade of debating such individuals and getting absolutely nowhere, there is no point me wasting my time discussing it further with you.

>Most ID proponents suggest that something could have evolved or it could have been designed.

It all depends on one's definition of "evolved". If it is in the sense "the standard scientific theory [of evolution] that ... God [or an Intelligent Designer] had no part in this process" (my emphasis):

"Facing such a reality, perhaps we should not be surprised at the results of a 2001 Gallup poll confirming that 45 percent of Americans believe `God created human beings pretty much in their present form at one time within the last 10,000 years or so'; 37 percent prefer a blended belief that `human beings have developed over millions of years from less advanced forms of life, but God guided this process'; and a paltry 12 percent accept the standard scientific theory that `human beings have developed over millions of years from less advanced forms of life, but God had no part in this process.'" (Shermer, M.B., "The Gradual Illumination of the Mind," Scientific American, February 2002. My emphasis)

then by definition, if something "evolved" then "it could [not] have been designed."

>Most scientists then accept the evidence mentioned above that shows it is happening, than the "but it looks designed to me" approach to determine which theory they prefer.

This argumentum ad populum fallacy "most scientists ... accept ... [something about evolution]", is often asserted, but no one has ever done a scientific survey of what most scientists do in fact accept about evolution. Indeed, as I observed in a recent post:

"It would be very interesting to see the results of such a worldwide survey of all scientists. It might well turn out that most scientists do not "consider evolution to be a scientific fact," in the sense that "God" (or an Intelligent Designer) "had no part in this process."

Stephen E. Jones