Re: soggy "down" maladaptive?

[Ronald Orenstein <ornstn@home.com>]

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.


--
Ronald I. Orenstein                           Phone: (905) 820-7886
International Wildlife Coalition              Fax/Modem: (905) 569-0116
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