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Re: Theory of Non-Avian Dino Extinction
On Wed, 26 Mar 1997, Paul Willis wrote:
> >Paul Willis wrote:
> >However, Is there not a large (foot long jaw) fossil of a Early Cret.
> >Labrinthodont Amphibian from this area as well.
> >Jim K.
> Perhaps Adam Yates would be better at answering this but the seaway tou
> refer to was quite a long way north (around 800km) and the exposed part of
> eastern Australia at that time resembled a reversed "L" with Dinosaur Cove
> on the bottom side of the horizontal and the seaway on the top side.
> I don't know about (and I am deeply suspicious about) ice being found in
> the sediments. There are indications that the temperature got down to
> around freezing point, so yes, it did still get pretty cold but appreciably
> warmer than similar latitudes today (80 degrees south).
> Similarly, as Jim points out, the presence of large labyrinthodonts and
> crocodiles in the site indicates that the climate was quite different from
> modern expectations.
There is indeed a temnospondyl from the Early Cretaceous of Victoria, it
is a chigutisaurid, quite similar to the Australian Jurrassic Siderops
kehli. There is a lot more than one jaw, we have several jaws (one almost
perfect) clavicles, vertebrae and fragments of pterygoid (a very
diagnostic bone amongst temnospondyls). BTW the paper describing this
material should have been out years ago unfortunately the Editor(s) of
the journal it was sent to have sat on the paper and have refused to
return the manuscript.
Most recently the back part of a skull was found, this is still being
prepared in the vert. palaeo. lab at Monash Uni. All the temno bones come
from one horizon in the Strezlecki Group, outcropping to the east of
Melbourne. The Strezlecki Group (Hauterivian) is older than the Dinosaur
Cove deposits (which belong to the Aptian, Otway Group) wich outcrop to
the west of Melbourne. No crocodiles are known from the
Stezlecki group conversely there are no temnos in the Otway Group where
crocs are found. Tom Rich thinks this may be an example of competative
replacement, I'm not so sure.
Hope this was of interest to someone.