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RE: The Croc That Wanted to Be a Dinosaur
Jay <email@example.com> wrote:
Except that Chatterjee had already named Shuvosauridae in 1993.
Thanks for the correction - I'd forgotten about that one.
Jeff Hecht wrote:
What I find fascinating is that the suchians and the true dinosaurs evolved
in parallel with similar traits through the Triassic, much as the two lines
of birds did in the Cretaceous, looking quite similar except for bones in
the ankles and legs that distinguished them. There also are parallels in
extinction patterns. The end-Triassic extinctions wiped out the
dinosaur-like crocs; the end-
Cretaceous extinction wiped out the enantiornithes.
The non-crocodylomorph suchians certainly bit the dust at the end of the
Triassic. Some rather theropod-like crocs (as in 'crocodylomorphs')
persisted into the Middle Jurassic (like _Junggarsuchus_) and even the Late
Jurassic (_Hallopus_/_Macelognathus_). These 'sphenosuchians' were rather
small, gracile, and cursorial, with an erect dinosaur-like posture.
The poor Suchia were whittled away throughout the Mesozoic and Cenozoic,
with the various suchian groups disappearing over a very long period of
time: basal suchians (shuvosaurs, aetosaurs, etc), 'sphenosuchians',
protosuchians, thatalattosuchians, dyrosaurs, sebecosuchians... until only
one lineage was left: the crown-group crocodylians.