Re: Archaeopteryx

[Dinogeorge@aol.com]

In a message dated 6/16/03 2:36:22 PM Pacific Daylight Time, 
npharris@umich.edu writes:

<< I think Mike is right, though:  the manual digits of _Allosaurus_, 
 _Struthiomimus_, _Deinonychus_, or _Troodon_ are pretty clearly homologous 
to 
 those of birds.  It's basal forms like _Eoraptor_ or _Herrerasaurus_ that 
you 
 have to worry about. >>

There's not much left of the digits in modern birds (which is why there is a 
frame-shift problem in the first place). Early fossil birds with digits 1-2-3, 
however, may not be terribly closely related to modern birds; we haven't yet 
excluded the possibility that there were early birds with digits 2-3-4. Many 
of what we call theropod dinosaurs could just be the flightless descendants of 
1-2-3 birds.

Not that I think any of this is very likely, but the possibilities remain.