RE: semilunate carpal

[rbi <rbi@dana.ucc.nau.edu>]

>To me, the simple mechanical reasons
>for discarding the ground-up hypothesis are sufficient, so the birdlike
>nature of the common ancestor is the favored hypothesis over the
>velociraptorlike nature.

I thought Caple, Balda, and Willis on their paper on the physics of preflight 
pretty convincingly argued that the ground-up track was physically and 
mechanically possible, and that even small development of feather-like 
integument would aid a cursorial predator.  Also, another problem I have with 
BCF is that the most derived theropods look the most like birds, yet the more 
primitive theropods (like coelophysoids) are less like birds, even though in 
BCF they should be closer to a bird ancestry.  For example, coelophysoids lack 
a semilunate carpal (please excuse me George if you have already addressed 
this in the thread).

Regards,
Randall Irmis