Re: solnhofen

["Tim Williams" <twilliams_alpha@hotmail.com>]

Dinogeorge@aol.com wrote:

> Nope. The predatory stroke was co-opted from the wingstroke. Where am I 
> >wrong?

Not wrong, so much.  It's just that BCF* has (at this moment in 
time)absolutely no support in the fossil record.  To my knowledge, there is 
no evidence of small, especially bird-like theropods in the Triassic.  Not 
even _Saltopus_, which George brought up earlier - is there any proof that 
_Saltopus_ is even a dinosaur?  The incompleteness of the fossil record 
aside, in this case the total absence of Triassic birds may be due to the 
fact that (quite simply) they didn't exist.


*To the uninitiated, BCF = Birds Came First.  A scenario proposed by George 
Olshevsky to explain the morphology and inferred behavior (such as the 
"predatory stroke" of the forelimb) of Jurassic and Cretaceous theropods.  
According to this view, the various groups of theropods we see in the 
Cretaceous, Jurassic (?and Triassic) are in reality secondarily flightless 
birds.  Birds, under the BCF scenario, evolved in the Triassic, and later 
theropods are their descendents.  IMHO, BCF may be true in a limited context 
(I'm prepared to believe that oviraptorosaurs might be secondarily 
flightless birds) - but ALL ground-dwelling theropods representing birds 
that lost the power of stroke!!!???

(To be honest, I actually hope George is correct.  It would make a LOT of 
sense.  Alas, this far, the available suggests otherwise.)


Tim


------------------------------------------------------------

Timothy J. Williams

USDA/ARS Researcher
Agronomy Hall
Iowa State University
Ames IA 50014

Phone: 515 294 9233
Fax:   515 294 3163

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