Tuesday, September 21, 2010

Classic "Evidences" for Evolution

I am taking the opportunity to examine and discuss an older article by Carl Wieland for my own interest.

Niles Eldredge wrote a book called, The Triumph of Evolution, but Carl did not write concerning that book. Rather he looked at a review made by Jerry Coyne.

Coyne's coverage, while praising, expressed his opinion that Eldredge had short-changed his argument by not mentioning three classic and powerful arguments for evolution.

Those three are, according to Coyne.

Sightless Eyes
Yes, once again it seems that the evidence that eyes could arise through chance mutations and natural selection is that chance mutations and natural selection can destroy them.
I'm not sure why anyone (let alone a college professor) thinks that showing that something can be broken can prove that the same process which broke it is the same process that created it. There are, after all, a myriad of ways to break [insert whatever mechanism you like here] but I can guarantee you that none of those ways were used to build it in the first place. Nor can they.

Hairy Embryos
Whilst we were in our mother's womb, we were covered in hair. Lots of it. Embryonic recapitulation has a long and murky history but surely lanugo is a gift from the evolutionary gods to their devoted followers.
Well, not so much.
As Wieland points out, infants and the unborn are no more hairy than adults. We have the same number of follicles, it's just the type of hair that changes. Lanugo gives way to vellus hair on the body, while terminal hair is always found on the head. At puberty in men, vellus hair gives way to terminal hair over much of the body, while women don't experience quite as much change (or at least we hope they don't). Interestingly, baldness isn't the result of losing hair, but the result of follicles switching from terminal hair production to vellus hair.

Island Migrants
Here Coyne attacks a strawman belief that creationists believe that all extant species were created in their present locations, he uses the example of oceanic islands. Short answer. They don't.
As Wieland points out, the post-flood dispersion model does create an expectation that only organisms with a mechanism to reach those islands would be there. The ability to swim or fly would get them there, but those without those skills would have to hop a lift, either with a natural raft or perhaps with human explorers. Natural selection in their island home would allow for the speciation that produces the definitive island kinds.

Three classic and powerful arguments for evolution? If they are, then evolution is in trouble.

I have heard that, while in other countries, "professor" is a title that indicates an advanced degree in a subject, in the United States it merely means one allowed to lecture at a university. That does somewhat cheapen the title.

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