Wednesday, December 9, 2009

Ardi Comes to Town!

Well, actually it was Tim White who came, to talk about Ardi. It was a pleasure to see his impressive pictures of the Awash Valley of Ethiopia, where the fossilized bones of Ardi and so many other species were found, as well as to hear his description of the truly painstaking work it was over 15 years to piece together the parts of the skeleton they have, and to catalog all the other fossils they found over many field seasons.

And it was fascinating to get a glimpse into the passion that drives White's life's work. As he pointed out, in The Descent of Man, in an often cited passage, Charles Darwin is frequently read as predicting that human progenitors originated in Africa.
In each great region of the world the living mammals are closely related to the extinct species of the same region. It is therefore probably that Africa was formerly inhabited by extinct apes closely allied to the gorilla and chimpanzee; and as these two species are now man’s nearest allies, it is somewhat more probable that our early progenitors lived on the African continent than elsewhere.
Though some scholars quibble with how prescient Darwin really was about human origins here, given the lack of fossil evidence at the time, White clearly seems to feel that he is a direct intellectual descendant of Darwin's, rising to the challenge Darwin laid down so long ago. The man of vision is there by his side as Tim scours the earth for our early ancestors in the Awash Valley.

White has a deep appreciation for his finds as important pieces of world heritage, as well as for their value as direct confirmation of Darwin's prediction. Of course, as he also said, we don't need the fossils to know that our closest ancestors lived in Africa and to know something about the time it has taken to make us from them; DNA sequence data have long ago settled that to within a reasonable approximation.

In his talk, Tim finished up by listing a number of ideas of Darwin's about human origins that have turned out to be true, supported by the fossil evidence (which he also discusses in an essay on the National Science Foundation website honoring the 150th anniversary of the publication of the Origin).

But Darwin's predictions about inheritance are much less au courant in molecular biology because he was so wrong about so much, and the field has come so far in 150 years (and in fact, Ken also has written an essay that appears on the NSF site, where he chips away a bit at the often rather uncritical Darwinian ancestor-worship). This is in no way to detract from Darwin, who set the research stage for the biologists who followed him, even where he was wrong, or making wild guesses (which he did quite a lot of).

Darwin recognized the importance of inheritance (as had some of his predecessors as well as Wallace), but his ideas were very wrong and much more conventional than the usual image of Darwin-the-pathfinder. We know a lot better today, and it's possible to recognize Darwin's fundamental insights -- common origin, life as history, and natural selection as a force (given the right conditions), and nothing yet discovered by biology contradicts these facts of life -- while also recognizing where he was wrong. It's important to do that, because otherwise the Origin of Species can morph into an equivalent of the Bible, and that would not be good for science.

Darwin is still treated by many molecular biologists as having the same kind of driving presence as Tim White the paleontologist seems to feel he has, however. But that is a rather careless view that rests on assumptions about natural selection as an all-powerful force, and the inference, without really reading him carefully or looking at data critically, that Darwin's was The Word.

That reservation aside, it was still nice to hear that as Tim trudges over the blistering sands of Ethopia, he feels Darwin watching over his shoulder.

12 comments:

Holly Dunsworth said...

Tim White and Alan Walker (dressed like Jedis) are watching over my shoulder when I'm scampering around Rusinga.

Ken Weiss said...
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Anne Buchanan said...

This is a great image, Holly -- and looking over Tim's and Alan's Jedi shoulders are Darwin and Wallace. Ken says Darwin may be only figuratively there because he was a non-believer, so I assume he's undressed, but Wallace turned to spiritualism later in life, so he may actually be there. Dressed as?

Holly Dunsworth said...

Wallace is dressed as Darwin. Ha!

Holly Dunsworth said...

And when I'm lurking around the shoulders of future paleontologists, I'll be dressed as Lara Croft.

Holly Dunsworth said...

or Laura Ingalls Wilder, depending.

Anne Buchanan said...

Ha, Holly! What inspiration! And, sadly, you're probably right about Wallace.

Ken Weiss said...

Now here's something interesting -- very interesting! In light of this rather Voodooish set of exchanges, I was looking closely at the Ardi bones and wondering....

And then I went to the few available pictures of Darwin and Wallace. The nose, the brow, the face. And the effects of walking stooped over for many years in tangled rainforest.

Yes, it's pretty clear: Ardi IS Wallace!

EllenQ said...

I want dead people to peer over my shoulder when I work! But seriously, I do think it is important to acknowledge what Darwin got wrong for just the reason Anne pointed out. If Origin turns into a Bible of sorts, then the anti-evolutionists (the Sith Lords if you will) can simply attack Origin instead of actually dealing with all of the modern evidence. This was, in part, the tactic used by Ray Comfort in distributing his distorted version last month.

Ken Weiss said...

Ellen,
This is a very important point and it's good that you made it. A few years ago I had a student, yes here at dear old Penn State, who came up to me after a class in which I had pointed out problems in Darwin, and thanked me profusely.

He was from a fundamentalist family and had thought that we, like they, went to our Received Word to answer questions in biology.

An important point is that the vast majority of biologists have never read Darwin, and that one need not do so to be a good biologist. That's for just the reason you point out: our effort was inspired 150 years ago by Darwin, but we live by the evidence, and it is no threat to Darwin's reputation that he was wrong here and now.

Even if some day you or some other very smart student (which means, of course, a Penn State student) comes along and shows that evolution as we know it was a misperception of how life works, we would still recognize Darwin's contribution to human history, much as we do Aristotle's or Newton's, despite their being wrong on lots of important points.

Mong H Tan, PhD said...

RE: What a scientific and critical reading of Darwinism!

Anne cautions above: Darwin recognized the importance of inheritance (as had some of his predecessors as well as Wallace), but his ideas were very wrong and much more conventional than the usual image of Darwin-the-pathfinder. We know a lot better today, and it's possible to recognize Darwin's fundamental insights -- common origin, life as history, and natural selection as a force (given the right conditions), and nothing yet discovered by biology contradicts these facts of life -- while also recognizing where he was wrong. It's important to do that, because otherwise the Origin of Species can morph into an equivalent of the Bible, and that would not be good for science.

Amazingly, I just revisited the accuracy and the predictive power of Darwinism here: “Matthew Cobb reviews two evolution books -- RE: Revisiting Darwin’s “tree of life” sketch-hypothesis!?” (WhyEvolusionIsTrueUSA; December 5). Clearly, Darwin’s prediction of Tim White’s, et al, fossil of “Ardi” was based on his “geogenic development” of ancestry of the “tree of life” theory, that he presented in his 1859 seminal book “The Origin of Species;” and not based on the “inheritance” or the misguided “pseudo-genetic centricity” as the world renowned neo-Darwinist-reductionist Richard Dawkins has had asserted in his 1976 book “The Selfish Gene.”

Furthermore, Anne concludes: Darwin is still treated by many molecular biologists as having the same kind of driving presence as Tim White the paleontologist seems to feel he has, however. But that is a rather careless view that rests on assumptions about natural selection as an all-powerful force, and the inference, without really reading him carefully or looking at data critically, that Darwin's was The Word.

And, that is exactly what the neo-Darwinists, reductionists, have had treated or attempted to dogmaticize the classical Darwinism of “natural selection” theory as The Word; or The Universal Acid, as the renowned neo-Darwinism reductionist-philosopher coined in his 1995 book “Darwin’s Dangerous Idea.”

Best wishes, Mong 12/9/9usct2:17p; practical science-philosophy critic; author "Decoding Scientism" and "Consciousness & the Subconscious" (works in progress since July 2007), Gods, Genes, Conscience (iUniverse; 2006) and Gods, Genes, Conscience: Global Dialogues Now (blogging avidly since 2006).

Mong H Tan, PhD said...

RE: An addendum to omission above!?

In a moment of haste, I left out Daniel Dennett as the named, renowned neo-Darwinism reductionist-philosopher whose 1995 book “Darwin’s Dangerous Idea” that I referenced above. Sorry for the omission-negligence!?

Best wishes, Mong 12/9/9usct4:28p; practical science-philosophy critic; author "Decoding Scientism" and "Consciousness & the Subconscious" (works in progress since July 2007), Gods, Genes, Conscience (iUniverse; 2006) and Gods, Genes, Conscience: Global Dialogues Now (blogging avidly since 2006).