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-----Original
Message----- >Hello, I
have a question involving the types of enviroments that Therapsids could live
in. I have seen several illustrations by Bakker that showed woolly Therapsids
in snowy, wintery type enviroments. Is it know whether their were any of these
enviroments around when Gorgonopsians and such lived, or any fossil evidence of
them living in such a enviroment? > During the
early Permian, the gondwanan parts of the world experienced a massive
glaciation, so snowy environments definately existed as the therapsids were
evolving, but i'm not sure when gorgonopsians specifically appeared, and wether
they're before or after the widespread glaciation (i have a feeling they came
after it - of course that doesn't mean that 'wintery' environments weren't
around in high latitude areas (perhaps periodically rather than year-round).
There's a good book on therapsids at the University of Melbourne Biomed library
whose title i can't remember - i think it might be "Ecology
and Evolution of the Mammal-like Reptiles", or some similar title.
Anyway, it has a paper or two on Permian climate. I'm sorry i can't recall the
exact title (or the name of the paper), but i'll have a look next time i'm at
uni.)<< As far as
I can tell, there are no Early Permian theraspids (except for Tetraceratops, and I think that’s been moved back to
pelycosaurs, but I am be wrong). The article your refereeing to is Parrish, J.
M., Parrish, J. T,.and Ziegler, A. M., 191986, Permian-Triassic Paleogeography and
Paleoclimatology and implications for therapsid distribution: In: The ecology
and biology of mammal-like reptiles, edited by Hotton III, N,. MacLEan, P. D.,
Roth, J. J,. and Roth, E. C., Smithsonian Institution Press, p. 109-131. (It
just so happens to be on my bookshelf right behind me) After looking at the article I don’t know where Bakker got the idea of
theraspids in snow. Maybe there’s been more recent work?
Tracy L. Ford P. O. Box 1171 Poway Ca 92074 |