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Re: spine tables
Unfortunately I don't know much about vertebral morphology. What
exactly would these neural spine tables do?
Were they there to support or anchor the osteoderms above them (did
thyreophorans have spine tables?)? And what would they do in those forms
which lacked osteoderms (muscle attachment sites?)?
Mickey Mortimer wrote:
I disagree. A spine table is a structure formed by the distal transverse
expansion of a neural spine. Note a few quotes from Makovicky's (1995)
thesis on coelurosaur vertebral morphology-
on Microvenator- "The spine is not expanded into a spine table distally,
on Avimimus- "The distal end does not expand into a spine table." on
Saurornitholestes- "The tip bears a moderately expanded spine table, which
is proportionally smaller than in Deinonychus." "Dorsally the cervical
neural spine is expanded into a spine table."
on Archaeopteryx- "Each one has a straight dorsal edge that is not expanded
into spine table."
on Ornitholestes- "The distal end is more expanded lateromedially than it
at midheight, but it does not form a true spine table."
Finally, a character from his phylogenetic analysis- 23. Distal end of
dorsal neural spines not transversely expanded = 0.
Distal part of neural spine expanded to form a "spine table" = 1 (Gauthier,
Rob Gay wrote-
But also present in phytosaurs and aetosaurs. How well developed are they
those two groups that you mentioned as opposed to known armour-bearing
I couldn't say, lacking any good references on crurotarsans. Deinonychus
does have better developed spine tables than Ceratosaurus though.
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