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New refs
Well some more just came in:
From the latest Contributions to Geology, University of Wyoming,
volume 30, #2:
Cifelli, Richard L. 1994. Therian mammals of the Terlingua local fauna
(Judithian), Aguja Formation, Big bend of the Rio Grande, Texas.
pp. 117-136.
In the shadow of the dinos fauna - mammals from teeth of course -
some marsupials.
Also, a detailed taphonomic analysis of the Carnegie Quarry (Morrison):
Fiorillo, Anthony R. 1994. Time resolution at Carnegie Quarry (Morrison
Formation: Dinosaur National Monument, Utah): implications for
dinosaur paleoecology. pp. 149-156.
Suggests that a detailed analysis of the taphonomy of the quarry shows
an accumulation time of a few months to a few years and not that of
more typical bone rain deposits which can be over 1000+ years. This
suggests that you can actually talk about co-existence of taxa and
suggests also, on the basis of tooth-wear patterns in Camarasaurus
and Diplodocus that there was some resource partitioning of the food
resources between the two. No surprise - would be interesting, if it
works, to see if there is partitioning among age classes within taxa...
In a similar vein (jugular?) there is, as mentioned earlier by someone:
Varricchio, David J. 1995. Taphonomy of Jack's Birthday Site, a diverse
dinosaur bonebed from the Upper Cretaceous Two Medicine Formation of
Montana. Palaeo, Palaeo, Palaeo 114:297-323 (that's geography,
climatology & ecology to those who don't call it palaeo cubed)
Notes that it comes from a small, shallow floodplain lake with
a transition from lake through shoreline to marginal shoreline/
floodplain. 10 taxa of dinos and a variety of non-dino faunal
elements making it a nice faunal sample for the region during
Two Medicine Formation time (~74 ma). There's a time-averaged
allochthonous element (transported in) and the more interesting
associated local fauna which includes iguanodontids (3), Hypacrosaurus,
Prosaurolophus and Gryposaurus as well as Troodon. The remains of these
are clustered together. That is, taxa tend to be found more with other
remains of the same taxon that you would expect at random. It's also
the first described association of more than one Troodon (4 actually).
He then discusses some possible mechanisms for the association including
his favored drought or drought/disease (botulism) but they could also
be single events as well. Nice study from my first view.
Then there's:
Little, C.T.S. & M.J. Benton. 1995. Early Jurassic mass extinction:
a global long-term event. Geology 23(6):495-498.
Summary of the end-Pliensbachian event (187 ma) suggesting it decimated
lots of marine inverts worldwide. Wish the terrestrial deposits were
up to looking for it on land more.
That's it from within the beltway, Ralph Chapman, NMNH