[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
Re: questions about the Odontochelys study
Augusto Haro wrote:
All right, but it was just an example that turtles with a heavy
cuirass are relatively fast, and that I doubt that turtles with less
completely covering shells, as the snapping, can really be faster.
Just to say I do not know exactly to what is decreased coverage of the
bony shell in turtles related.
Is there a particular reason that you doubt a chelydrid could be
faster? In any case, the shell reduction, especially in the plastron,
might have more impact on aquatic locomotion than terrestrial
walking. For mata-matas, as least, the plastron reduction allows the
animals to take a somewhat more erect stance when punting along the
bottom, and appears to greatly increase effective stride and speed
(they're actually quite rapid movers when need be). This is all
unpublished, personal observation, however (albeit many years of
personal observ. for that particular taxon).
For pelagic aquaflyers, specifics of shell reduction or expansion
might be related to required forelimb excursions, as well as the
specific bracing important for mirrored stroke utilization (I
recommend taking a look at Stephen Godfrey's 1984 manuscript on
plesiosaur locomotion and aquaflying).
Michael Habib, M.S.
Center for Functional Anatomy and Evolution
Johns Hopkins School of Medicine
1830 E. Monument Street
Baltimore, MD 21205