Thursday, November 13, 2008

Evolution and the Moving Eye of the Flatfish

I am not a fan of the evolution/Creation debate. Aside from the frustrating fact that it never evolves beyond the same arguments, vitriol and narrow stereotyping, I am fundamentally embarrassed by some of the views espoused by the Creation side - and no argument is more embarrassing to me than the challenge, “That could not have evolved!”

This approach is as old as Darwin, and, indeed, he was stymied by a few cases from its class, such as, “The eye is so complex, it could not have evolved in successively functional steps.” It demands either a logical explanation for an evolutionary step, or, in the absence of such an explanation, it demands physical evidence that such an evolutionary step occurred.

But I don’t like or trust this approach.

One reason I don’t like this argument is that it rarely considers new evidence or arguments, relying instead on outdated literature. Every few years scientists discover another missing link, or develop another explanation for an unlikely evolutionary process, but the creationists never update their data to include, or refute, these findings. In response, evolutionists reject the creationist view as outdated – which, in this respect, it is.

A second reason I don’t like this argument is that it sets up an unfair logical playing field, demanding Reason from the evolutionist side but not from the creationist side. The evolutionist does not have a good theory and does not have all of the evidence to support his theory, and so the creationists are going to call him on his lack of evidence. But when the evolutionist calls the creationists on their own lack of evidence – ie where is Noah’s Ark? – then he is told to accept it on faith. If we can accept Creation on faith, the scientist must be able to accept a theory even in the absence of a complete constellation of evidence.

But the third and strongest reason I don’t like this approach is this: Evidence which is missing now may well be discovered later. Theories which are gapped today might be made whole with the passage of time. People who pin their hopes on today’s inadequate science are due for a surprise tomorrow.

Witness this ScienceDaily report from July (I meant to blog it ages ago, but never had the chance):
Flatfish Fossils Fill In Evolutionary Missing Link
Opponents of evolution have insisted that adult flatfishes, which have both eyes on one side of the head, could not have evolved gradually. A slightly asymmetrical skull offers no advantage. No such fish -- fossil or living -- had ever been discovered, until now.
All adult flatfishes--including the gastronomically familiar flounder, plaice, sole, turbot, and halibut--have asymmetrical skulls, with both eyes located on one side of the head. Because these fish lay on their sides at the ocean bottom, this arrangement enhances their vision, with both eyes constantly in play, peering up into the water…
But in the 10 July 2008 issue of Nature, Matt Friedman, graduate student in the Committee on Evolutionary Biology at the University of Chicago and a member of the Department of Geology at the Field Museum, draws attention to several examples of such transitional forms that he uncovered in museum collections of underwater fossilized creatures from the Eocene epoch--about 50 million years ago...
Friedman examined multiple adult fossil remains of two primitive flatfishes, Amphistium and a new genus that he named Heteronectes.
"Amphistium has been known for quite some time," he said. "The first specimen was described more than 200 years ago, but its placement in the fish evolutionary tree has been uncertain ever since. Close examination of these fossils yield clues that they are indeed early flatfishes."
The most primitive flatfishes known, both Amphistium and Heteronectes have many characteristics that are no longer found in modern flatfish. But the one that caught Friedman's attention was the partial displacement of one eye, evident even in the first Amphistium fossil discovered over two centuries ago.
"Most remarkably," he said, "orbital migration, the movement of one eye from one side of the skull to the other during the larval stage, was present but incomplete in both of these primitive flatfishes." For both sets of fossils, the eye had begun the journey but had not crossed the midline from one side of the fish to the other.
"What we found was an intermediate stage between living flatfishes and the arrangement found in other fishes," he said. These two fossil fishes "indicate that the evolution of the profound cranial asymmetry of extant flatfishes was gradual in nature."

I certainly believe that Gd created the universe, and I am no wiser than anyone else regarding the mechanism Gd used. But this I do know: Arguments predicated on " I found a gap in your theory" and "Where is your proof?" are doomed by the march of theoretical development and investigation.

4 comments:

  1. If the proponents of evolutionary theory were content to just put it forward as a mechanism and leave it at that, then the theory would probably not still generate as much controversy as it does; it would be like Copernicus' view of the solar system - something that was hotly disputed in its time, but which is generally accepted today even by the most literal-minded Orthodox Jews (and lehavdil, fundamentalist non-Jews).

    The problem is that evolution has been used as an argument that a Creator is not necessary to explain why our world looks as it does. This, unfortunately, is the public face of the evolutionary position.

    So your "unfair logical playing field, demanding Reason from the evolutionist side but not from the creationist side" is perhaps not so unfair. The creationist believes in an all-powerful G-d who can manipulate reality however He sees fit; what science declares impossible is all in a day's work for Him. Whereas for the evolutionist - at least the atheistic one - there exists nothing that is not (at least in principle) explainable by reason and amenable to scientific inquiry of its causes.

    That said, the problem with a creationist position that relies on "gaps" ("Intelligent Design," et al) is not only, as you mentioned, that it's prone to failure; the bigger problem is that it diminishes G-d by relegating His creative acts to a few "corner cases" and assuming that blind fate (dignified with names such as "stochastic process") is responsible for everything else.

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  2. I certainly agree that the politicizing of evolution has been the trigger for much strife, but I don't think the other point - about the fairness of the playing field - follows.

    Certainly, the evolutionist believes that all could be explained by reason. However, the absence of a current theory which can explain all cases is hardly proof that such a theory is impossible.

    Re: Your last point - I don't think they believe they are relegating Gd to those gaps. Rather, they take those gaps as proof that Gd is handling everything.

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  3. The basic problem is that evolution and creationism are answering completely different questions.

    Scientists exploring evolution are attempting to explain HOW the world we have has come about.

    Creationists are concerned with WHY the world is the way it is, and have made the mistake of thinking this has something to do with HOW. Thus they frequently look like irrational idiots.

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  4. Tzipporah-
    Oh, come now; both sides cross that logical line, I think.

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