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Re: New Cretaceous bird and other papers




Well I certainly agree about the timing problem. Our ability to calibrate "molecular clocks" will eventually be more accurate, but at present they are crude estimates that should be taken with a grain of salt.
I too would bet these families split after K-T, sometime during the Paleocene. We have to be skeptical of such dating, as we are talking about molecules evolving, not something as predictable as the number of atoms decaying at a constant rate.
If these families did split later in the Paleocene, we certainly won't be confined to Antarctica for evidence, so we shouldn't let a molecular estimate like this dissuade us from searching for fossil evidence in places other than just Antarctica.
------ Cheers, Ken
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David Marjanovic wrote:
:-) I'll try -- I'll just question the reliability of molecular clock estimates that cross the times of mass extinctions. Also, when you take the lower end of the range, you might end up with Accipitridae and Falconidae separating just after the K-T -- as part of the Paleocene neornithine radiation. Well, who knows. Let's find a fossils. Unfortunately most will be in Antarctica respectively eroded off it by glaciers. :.-(





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