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Re: soggy "down" maladaptive?



At 04:47 PM 27/04/01 +0000, Ken Kinman wrote:

Another argument put forward by Feduccia and others is that downy feathers would be maladaptive as insulation (soggy feathers result in hypothermia at night?) unless it was only on the young and a parent could shield the young from getting its down wet.
How does one best argue against the "downy feathers get soggy and are thus maladaptive" argument?

For one thing, I do not see its relevance. Whatever else the structures on Sinosauropteryx, the new critter etc are, they are certainly not "down" in the neornithine sense - ie a plumulaceous puff arising from a common base. It may very well be true that a coat composed entirely of down might be a problem for an adult - but who is claiming that there ever was such a creature? In fact there seems (as far as I can see) no evidence that downy underfeathers were present in non-avian dinos or even in Archaeopteryx; they may have evolved at a later stage.



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Ronald I. Orenstein Phone: (905) 820-7886
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