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Re: silly question



 From: Gary Vatnsdal <rrlgary@cc.umanitoba.ca>
 > 
 > But feathers are another thing. There are
 > some coasting mammals like flying squarrels, and some flying mammals like
 > the bat and some flying dinosaurs like archaeopteryx. But what strange force
 > of nature  started the development of these feathers? 

A good question, but a simple one to answer.

Feathers originally evolved for *warmth*.  That is, the primal,
ancestral, function of feathers was (and still is) insulation
(an important, nay vital, function in small endotherms).

The shift to use in flight was secondary - and only the tail
and wing feathers were significantly altered by that shift.
This sort of shift of a structure's use after it has evolved is
a common theme in evolution.

Now, just exactly what prompted the enlargement of the arm
feathers of the proto-bird into something large enough to be
at least a parachute is still controversial, and very unclear.

 > Is there fossil
 > record of this happening? Were Dino birds well developed when the K-T
 > event took place?

Birds were long established at the K-T boundary.  Archaeopteryx,
the oldest established bird, is from the Late Jurassic, about
70 million years prior to the K-T boundary.  There is a modest,
if very fragmentary, fossil record of birds from the Cretaceous,
showing a substantial variety of birds by the end of the Cretaceous.
[Even some relatively specialized forms, like ducks and cormorants,
had already evolved by then].

swf@elsegundoca.ncr.com         sarima@netcom.com

The peace of God be with you.