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Re: Carniadactylus paper and pterosaur ontogeny




On Aug 1, 2009, at 9:38 AM, Mike Habib wrote:


This is just nonsense. Isometric growth has been demonstrated for the forelimb-hindlimb ratio -- and that's it. Skulls most obviously didn't grow isometrically in pterosaurs; neither do they anywhere else.

You're standing by an unproven paradigm. Show me one juvenile and one associated adult to prove your statement.

None of the embryos discovered are geometrically similar to the adults.

Not true. Trace and reconstruct the bones. Then get back to me. We'll compare notes.

Furthermore, none of the animals you are suggesting as juveniles are geometrically similar to the adults, either, and if those animals are, in fact, some kind of tiny adult, then you don't have a sample to demonstrate isometry in the first place.

A little confused, Mike. The embryos and hatchlings are the only ones I'm suggesting are similar to the adults. Plus the little Pteranodon.

It's also worth noting that for pterosaurs to be flighted at small size and retain flight ability through growth, they cannot grow isometrically.

1. Only Unwin said they were flighted at hatching.

2.Your statement is not backed up by the literature. Please share.

Best,

David



Cheers,

--Mike


Michael Habib, M.S.
PhD. Candidate
Center for Functional Anatomy and Evolution
Johns Hopkins School of Medicine
1830 E. Monument Street
Baltimore, MD 21205
(443) 280-0181
habib@jhmi.edu