[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
Re: bird arms
<< If the radius and ulna of these animals could not cross then surely the
birdlike posture with the arms tucked back is not possible. >>
Have a look at a chicken wing. It is not necessary to cross the radius and
ulna at all to fold the wing. The semilunate carpal evolved to allow this
flexion without mammalian style radius/ulna crossing.
Mark Orsen and I made much of this in our Dinofest 98 paper, but it seems
like the Symposium volume will never be published.
Thomas P. Hopp