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Thud, thud, thud, thud.
No that is not the sound of a tyrranosaur persuing it's prey, it is the
sound of me hastily backpedalling. My edition of Current Contents on
Diskette is oriented towards environmental biology and so appears not to
extract the major paleontological journals. So, I will post what I have. I
may rectify the oversight in the future.
The first two articles are not directly dinosaurian in nature but are very
related to their ecology, ie. temperature estimates and insect assemblages
for the Cretaceous.
Sellwood, B.W., Price, G.D., Valdes, P.J.,"Cooler estimates of cretaceous
temperatures. Nature, August 11, 1994. 370, 6489, 453-455.
"The Cretaceous period is thought to have been warmer than the present, with
higher concentrations of atmospheric greenhouse gases such as carbon
dioxide. It has therefore been suggested that this time period could be used
by modellers as an analogue for future climate change. But the Cretaceous
Equator-to-Pole temperature gradient was flatter than today's, leading some
to suggest that Cretaceous climate arose from a combination of factors, with
higher atmospheric carbon dioxide concentrations leading to general warming,
and other factors, such as increased ocean heat transport, leading to
flattening of the latitudinal temperature gradient. Here we report new
records of ocean palaeotemperature for Cenomanian sites in the Atlantic and
Pacific oceans which, together with a re-evaluation of published data, cast
doubt on the idea that the Cretaceous period was generally warmer. These
data confirm that the latitudinal temperature gradient was flatter, but
suggest that the global mean temperature, was much cooler than previously
believed, with minimum mean equatorial temperatures close to present values
and polar temperatures close to 0 degrees C. In the light of these findings,
the climatic role of atmospheric carbon dioxide in determining Cretaceous
climate is unclear, suggesting that the Cretaceous cannot be used as an
analogue for future climate change."
Pike, E.M.."Historical Changes in Insect Community Structure as Indicated by
Hexapods of Upper Cretaceous Alberta (Grassy Lake) Amber", Canadian
Entomologist, May-June 1994.126, 3, 695-702.
"Species richness and relative abundance of arthropod taxa from an Upper
Cretaceous (Campanian: 75 Mya) amber deposit in Alberta are described. About
130 hexapod species have been recognized to date from this deposit, making
it the most diverse Cretaceous insect assemblage so far known. Taxa present,
in order of abundance, are Hemiptera (66 specimens per kg), Diptera (28),
Acari (21), Hymenoptera (13), Aranaea (12), Psocoptera (4), Coleoptera (2),
Blattodea (1), Thysanoptera (1), and Trichoptera (0.6). Representatives of
Lepidoptera, Collembola, Dermaptera, Mantodea, Phasmatodea, and
Ephemeropteraare are also present. In the total of 65 identified families,
15 are extinct. Only one of about 77 genera identified in this deposit is
extant. All recognized species are extinct. In comparison, virtually all
families reported from Baltic and Dominican Republic ambers are extant, as
are the majority of the genera. Morphology and feeding structures are well
within the variation seen in modem insects. It is hypothesized that the
taxonomic structure of modem insect communities was well established before
the end of the Cretaceous and that the structure and interrelationships of
insect guilds were also very similar to those of today."
Unwin, D.M., Bakhurina, N.N.,"Sordes pilosus and the nature of the pterosaur
flight apparatus". Nature, September 1, 1994. 371, 6492, 62-64.
"It is now generally accepted that pterosaurs, Mesozoic reptiles, were true
fliers, but the nature of their flight apparatus is still much disputed.
Evidence has been presented in favour of bird-like reconstructions with
narrow, stiff wings free of the legs and bat-like reconstructions with
extensive wings incorporating both fore and hind limbs, but the Solnhofen
Limestone pterosaurs, upon which these models are based, are not
sufficiently well preserved to resolve these conflicting interpretations.
Here we present a new model, founded on Sordes pilosus from the Jurassic of
middle Asia, in which exceptionally well preserved wing membranes show that
the hind limbs of pterosaurs were intimately involved in the flight
apparatus; connected externally to the main wing membrane and internally by
a uropatagium, controlled by the fifth toe. Sordes also reveals that,
uniquely among flying vertebrates, pterosaurs had a structurally
non-homogenous flight surface with a stiffened outer half and a softer, more
extensible inner region."