Prominently featured on the home page is an article by Jonathan Wells.
Is Francis Collins Right about Evolution?Wells is referring to the evidence of shared pseudogenes and other genomic signatures of common descent. This won't do, according to Wells. Collins is not one of the good guys.
Francis Collins feels that intelligent design poses a serious problem to Christian belief because it rejects Darwinian evolution, which he feels is supported by overwhelming evidence. But the only evidence Collins cites for Darwin’s mechanism of variation and selection is microevolution—minor changes within existing species. And the principal evidence he cites for Darwin’s claim of common ancestry is DNA sequences that he says have no function—though genome researchers are discovering that many of them do have functions.
Collins’s defense of Darwinian theory turns out to be largely an argument from ignorance that must retreat as we learn more about the genome—in effect, a Darwin of the gaps.
I wonder if Jonathan Wells has read a book called The Edge of Evolution? It was published in 2007. The author is Michael Behe—a Senior Fellow at the Discovery Institute. Behe also describes the evidence from pseudogenes. Here's an excerpt from pages 70-71.
When two lineages share what appears to be an arbitrary genetic accident, the case for common descent becomes compelling, just as the case for plagiarism becomes overpowering when one writer makes the same unusual misspellings of another, within a copy of the same words. That sort of evidence is seen in the genomes of chimps and chimpanzees. For example, both humans and chimps have a broken copy of a gene that in other mammals helps make vitamin C. As a result, neither humans nor chimps can make their own vitamin C. If an ancestor of the two species originally sustained the mutation and then passed it to both descendant species, that would neatly explain the situation.Behe and Collins are on the same page. They both recognize the powerful genetic evidence of common descent (macroevolution).
More compelling evidence for the shared ancestry of humans and other primates comes from their hemoglobin—not just their working hemoglobin, but a broken hemoglobin gene, too. .... In the region between the two gamma genes and a gene that works after birth, human DNA contains a broken gene (called a "psedugoene") that closely resembles a working gene for a beta chain, but has features in its sequence that preclude it from coding successfully for a protein.
Chimp DNA has a very similar pseudogene at the same position. The beginning of the human pseudogene has two particular changes in two nucleotides that seem to deactivate the gene. The chimp pseudogene has the exact same changes. A bit further down in the human pseudogene is a deletion mutation, where one particular letter is missing. For technical reasons, the deletion irrevocably messes up the gene's coding. The very same letter is missing in the chimp gene. Toward the end of the human pseduogene another letter is missing. The chimp pseudogene is missing it, too.
The same mistakes in the same gene in the same positions of both human and chimp DNA. If a common ancestor first sustained the mutational mistakes and subsequently gave rise to those two modern species, that would very readily account for why both species have them now. It's hard to imagine how there could be stronger evidence for common ancestry of chimps and humans.
That strong evidence from the pseudogene points well beyond the ancestry of humans. Despite some remaining puzzles, there's no reason to doubt that Darwin had this point right, that all creatures on earth are biological relatives.
I wonder if Jonathan Wells and Michael Behe talk to each other? I'd love to be a fly on the wall.
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