Re: help: reptile scale to bird feathers

["Mickey P. Rowe" <mrowe@xxxxxxxxxxx>]

Manfred Krautter <manfred.krautter@po.uni-stuttgart.de> asks:

> can anybody give me some hints how reptile scales developed into feathers

I think the best hint I can give you is that they probably didn't :-)
That's the story I've been getting from Alan Brush who's been studying
the biochemistry of feather and scale production.  His belief (going
back a few years now) is that feathers arose de novo.  Without getting
up you can search the dinosaur list archives
(http://www.cmnh.org/fun/dinosaur-archive/index.html) for some of his
writings on the subject.  In particular you might want to look at:

http://www.cmnh.org/fun/dinosaur-archive/1994Dec/0232.html

and you might want to write to Alan directly (the address listed in
that message is still current).

> and why?? Preparing a lecture, it would be great to get some information
> about this subject.

Well, if I were you I'd jump through hoops to make it clear that *why*
feathers evolved (initially) is largely unknown.  Most seem to think
thermoregulation was primary, but there are other ideas such as
providing aerodynamic drag and cushioning for falling arboreal
animals, or -- one of my favorites -- proposed by Jere Lipps and
Richard Cowan for display structures.  Richard's proposal has been
published in his book _History of Life_ (Blackwell, 2nd Ed. 1994).  He
also submitted it to the dinosaur list, so you can find it in the
archives -- sort Jan 1995 by author and read through the messages
written by cowen@geology.ucdavis.edu.

Hope people find this helpful.

--
Mickey Rowe     (mrowe@indiana.edu)