[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

re: Ichthyosaurus fossilised in mid-birth ??



re: fighting protoceratops/velociraptor: David Unwin once presented a
fascinating podium talk on this, and it is recorded as an abstract
(1995) in which, as I recall, the dune left exposed a left side limb or
two that disappeared, presumeably carted away by a non-digging
scavenger. Is that how others remember it?

re: ichythyosaurs, I'm on board with the mother dying, baby expulsion
post-mortem theory. I think the same thing happened in (and I know this
is old news redredged) pterosaurs.

Now that we know pterosaurs are lizards and not archosaurs, their
reproductive possibilities have changed. As archosaurs they would have
layed eggs at a very early stage in embryogenesis. As lizards a wider
spectrum of possibilities exists. They _could_ have retained the embryo
within the mother until the very latest stages of embryogenesis. Perhaps
this is why all three pterosaur eggs are a day away (or less) from
hatching, unlike most archosaur egg finds. They are also found as
singletons, not clutches. And it also might explain why I found so many
little softies near or emerging from mother cloacas or, in the case of
Longisquama, in the midst of the 'exploded' mid-section.

David Peters
St. Louis

Unwin, D.M., Perle, A. & Trueman, C. 1995. Protoceratops and
Velociraptor
preserved in association: evidence for predatory behavior in
dromaeosaurid
dinosaurs? JVP 15 (suppl. to 3): 57A.