Dinogeorge@aol.com wrote:
> But it's not a semilunate carpal. That came later in segnosaurs. Homologous, schmo-
> mologous.
Nonsense. The most basal known segnosaur _Falcarius_ has a semilunate carpal. Crikey, it's right there in the original description (Kirkland et al., 2005; Nature 435: 84-87)! _Falcarius_ is much more primitive than _Alxasaurus_, so the loss of the semilunate shape in the latter is probably secondary. Nevertheless, the wrist of _Alxasaurus_ did retain the trochleate articulation, which was integral to the maniraptoran 'swivel-wrist' (and retained in birds as part of the flight apparatus).
I confess to being bewildered by the "Homologous, schmo-mologous" statement. Oh well.
Cheers
Tim
Start your day with Yahoo! - make it your home page