[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
Re: Thou Shalt Not Climb!
Jaime Headden wrote:
More than likely, the animals were in trees before the selective
for arboreality became apparent. Not even *Archaeopteryx* is _arboreal_,
it was certainly scansorial. All other basal birds, begining at least with
*Confuciusornis*, appear to be arboreal, with derived hindlimb for
branch-sitting (maybe not "perching" per se) and reduced forelimbs for
climbing, etc., while birds antecedent in anatomy seem to be a lot less
inclined to the trees.
Jaime, out of interest, could you (briefly) describe what anatomical
features in the hindlimb distinguish "branch-sitting" from "perching".
Nearly all the long-tailed Liaoning birds have ropbust
hindlimbs and the "scampering" forelimb structure, leading one to suspect a
form of four-legged tree-climbing habitus with equal measures on the
the rocks, or in the trees, without any selective advantage (yet) for one
Can you explain exactly what is meant by a "scampering forelimb"? In other
words, what characters in the forelimb suggest that it was used for
scampering? How are these forelimb characters different from characters
associated with (say) predation?
BTW, I don't disagree with the idea that _Archaeopteryx_ and other basal
avians could have (and did) climb up trees. I'm just intrigued as to how
the anatomy of _Archaeopteryx_ supports this interpretation.
Who's that on the Red Carpet? Play & win glamorous prizes.