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Claims about "cooption"

EE's claim: Evolution via cooption can't really work.

Problems with claim:

EE almost acknowledges that "cooption" is a powerful evolutionary process. Cooption occurs when a given gene (or trait) acquires a new function, different from its original one. Genes can acquire new functions in several ways. Extra copies of genes are sometimes produced by DNA copying errors. These extra copies are free to mutate without disrupting the function of the original gene. Or, sometimes a mutation in a part of a gene can lead to the evolution of a new function in addition to the original one.1 (True JR, Carroll SB, 2003)

EE attempts to cast doubt on the power of cooption by making comments like this:

For one thing, the co-option hypothesis underestimates the problem of coordinating the necessary transformations. How does an undirected process incorporate the "borrowed" parts to form a new system -- without disrupting the old system? What natural process ensures that previously unrelated parts fit together well enough to form a new, functioning system? (EE p. 121)

The old system is not disrupted because a duplicate is modified, not the original. Gene duplication has been a standard part of evolutionary theory for decades.

EE's Claim: The scientist H. Allen Orr thinks cooption doesn't work.

Critics, including many neo-Darwinian biologists, contend that these questions remain unanswered, and are skeptical of the co-option hypothesis. As H. Allen Orr has said, "You may as well hope that half your car's transmission will suddenly help out in the airbag department."

What does Orr think about Behe's argument?

The first thing you need to understand about Behe's argument is that it's just plain wrong. It's not that he botched some stray fact about evolution, or that he doesn't know his biochemistry, but that his argument—as an argument—is fatally flawed.>
1 True JR, Carroll SB. Gene co-option in physiological and morphological evolution. Annu Rev Cell Dev Biol 2002;18:53–80.