Re: feathers, hair and Compsognathus

["Tim Williams" <T.Williams@cclru.randwick.unsw.edu.au>]

Jeffrey Martz wrote:

> Since _Archaeopteryx_ lacks a beak, wouldn't this then imply that beaks
> developed covergently, possible several times, within the Dinosauria?  Or are
> we talking about a reversal?

We're talking about a trait that evolved independently in several 
dinosaur groups.  To my knowledge, the most primitive sauropodomorphs 
(thecodontosaurids), the most primitive theropods (herrerasaurs) and 
even the most primitive ornithischians (lesothosaurids?) were beak-
less.
 
> What would an theropod be doing with a beak AND teeth?

Good question.

> Predentatans apparently used the beaks to crop and the teeth to chew
> but theropods do not have chewing teeth.  Oviraptor and caegnathids
> did away with the teeth almost entirely, didn't they?

Except the so-called "palatal teeth" in _Oviraptor_.

> LN Jeff
> 0-