Re: climbing dromaeosaurs and friends

["Scott Hartman" <scott_hartman@hotmail.com>]

> > > Why bother having a retro hallux >for prey manipulation< when the 
> > > forelimbs were already well adapted for this purpose?<<<

    Because small early fliers would have to grasp their prey as they 
ransitioned from flight-pursuit to tackling their prey so they can properly 
attack it.  This pedal use is similar to falconiformes, i.e. prey grasping 
an maniputation, but the actual hunting style would be very different.  
Early birds are not, after all, falconiformes.  But regardless of the 
reason, that's what the data shows.

> > > Retro hallux first appears in ceratosaurs, which strongly suggests that 
> > > the common ancestor of ceratosaurs and birds was a fairly good flier that 
> > > had found having a grasping/perching foot highly adaptive: distally 
> > > positioned retro hallux occurs in all theropods at ceratosaur grade or 
> > > above.<<<

    Which certatosaurs are you refering to?  Certainly well reserved Ghost 
Ranch Coelophysis didn't have a retroverted hallux.  I believe the hallux is 
preserved in Eoraptor, did anyone notice its orientation?
    I should point out that my model is incompatible with the BCF theory.  
If further evidence supports BCF, then my model for the evolution of flight 
will be wrong, although Archeopteryx's pedal morphology will still be most 
consistent with prey manipulation.

Scott
_____________________________________________________________________________________
Get more from the Web.  FREE MSN Explorer download : http://explorer.msn.com