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Re: Resetting the "molecular clock hypothesis"

Riv Biol. 2008 Jan-Apr;101(1):93-108.

Rivista di Biologia is a journal without peer-review that publishes creationist attempts to imitate the scientific process. It can be safely ignored on that basis alone.

There exists a remarkable correlation between genetic distance as measured by protein or DNA dissimilarity and time of species divergence as inferred from fossil records. This observation has provoked the molecular clock hypothesis. However, data inconsistent with the hypothesis have steadily accumulated in recent years from studies of extant organisms.

As usual, creationists are -- at best -- behind their times in their understanding of scientific knowledge. Even the ornithologists now understand that the molecular clock hypothesis holds only as a very, very crude approximation, that each clade, each gene, and lastly each base pair has its own speed of evolution.

Here the published DNA and protein sequences from ancient fossil specimens were examined to see if they would support the molecular clock hypothesis. The hypothesis predicts that ancient specimens cannot be genetically more distant to an outgroup than extant sister species are.

A very strict form of the molecular clock hypothesis would predict that. But why bother? We already know it is wrong. If I had been a reviewer on this manuscript, I'd have recommended rejection on the grounds that the author doesn't know what they're talking about. But, as mentioned, nobody was a reviewer.

Also, two distinct ancient specimens cannot be genetically more distant than their extant sister species are.

Does that mean anything?

The findings here do not conform to these predictions. Neanderthals are more distant to chimpanzees and gorillas than modern humans are. Dinosaurs are more distant to frogs than extant birds are. Mastodons are more distant to opossums than other placental mammals are.

More distant to opossums than _any other_ placental mammals are? Was the damage to the sequence counted as difference, or what?

The genetic distance between dinosaurs and mastodons is greater than that between extant birds and mammals. Therefore, while the molecular clock hypothesis is consistent with some data from extant organisms, it has yet to find support from ancient fossils.

Which extant birds and which mammals?

And what is this talk about distance anyway? Why not count apomorphies instead of differences? Oh, right, that's because...

Far more damaging to the hypothesis than data from extant organisms, which merely question the constancy of mutation rate, the study of ancient fossil organisms here challenges for the first time the fundamental premise of modern evolution theory that genetic distances had always increased with time in the past history of life on Earth.

Told you the author is a creationist: "Being ignorant, I believe that some unrealistic hypothesis is a fundamental premise of modern evolution theory, without which the theory would utterly collapse; this hypothesis is wrong (especially if my lack of understanding of the data is counted as evidence); therefore the theory of evolution is wrong; therefore the lack-of-theory of creationism is right; therefore Jesus. Praise the Lord!!!1!" (If you're bored, count the errors in the logic.)


Any discussion of this should be kept offlist, in order to avoid useless discussions of creationism (as required by http://www.lifesci.ucsb.edu/~mrowe/dinosaur/administrivia.php#no_nos). Please don't time me out just yet -- I'll be away from any computer from July 27th to August 9th anyway.