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Re: Relatively New Refs (long)
In a message dated 6/3/01 4:54:26 PM EST, david.marjanovic@gmx.at writes:
<< Pneumatic fossae and foramina are found on neural arches throughout
Archosauria, and maybe beyond. >>
Well, now, isn't this nice? In my dino/archo phylogeny, skeletal pneumaticity
is primitive to Dinosauria (not just "Saurischia"; secondarily lost in some
prosauropods and all ornithischians, supporting close relationship between
prosauropods and ornithischians) and is a feature consistent with the
lifestyles of small, arboreal reptiles. Since such animals include the common
ancestor of Archosauria, one would expect to find crocs with pneumaticized
skeletons somewhere in their early fossil record (pneumaticization would be
lost in aquatic lifestyles because it would make the skeleton too buoyant,
which is likely why it didn't occur in later crocs).