[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
Re: polarity of bipedality in dinosaurs
On Mon, 23 Sep 1996 Dinogeorge@aol.com wrote:
> Loss of outer digits of the manus in theropods
No one has ever answered this question for me: are digits IV and V
clawed?? I know they are unclawed in some dinosaurs. If they are unclawed
in theropoda, then there is little reason to keep them since they are of
little use in walking (possibly why ornithopods retain them) and little
use in grasping. If these digits were unclawed, then this would seem to me
to be a more parsimonious explanation of their loss.
> Scarcity of pre-_Archaeopteryx_ "birds," and existence of all so-called "bird
> precursor" dinosaurs in strata >younger< than that of _Archaeopteryx_
Scarcity of pre-archaeopteryx birds is no more a weakness than
is scarcity of arboreal dinosaurs.