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Re: Welcome, Zhuchengceratops!



> So in a way, Sarah Palin was right. :-)

I wouldn't quite put it that way... :-) but there is indeed no tectonic feature at all that lines up with the Bering Strait. The Bering Strait is an epicontinental sea that falls dry every ice age. The plate boundary between North America and Eurasia is the Lena valley. The Lena delta is the rotation point; north of it, NA and Eurasia drift apart (widening the Atlantic and Arctic Oceans), south of it they drift together (creating the Verkhoyansk mountains.

OK, let's make it more complicated. The North American craton (the solid, Precambrian continent; the granite slab) doesn't reach all the way west, it ends at the Rocky Mountains. The space between there and the Lena consists of accreted terranes. IIRC, the boundary between two of these runs through the Bering Strait -- _at a right angle_, east-west instead of north-south.

 As someone interested in paleobiogeography, I'm really, really eager
 for more discoveries from this region. I'd been predicting that
 derived ceratopsians would be found in Asia since about 11 or 12
 years ago (as perhaps a fair few others have). Of course, it's the
 ecological *differences* that are truly illuminating, I think, even
 if the similarities serve to better underscore them.

It has long been suspected that the difference isn't geographic but ecological -- the "Asian" fauna of the Late Cretaceous is the dry-upland fauna in this view, and the "North American" one the wet-lowland fauna. This is supported by the Turonian of Uzbekistan -- wet lowland at the shore of the Turgay Sea -- which has yielded mammals similar to contemporaneous North American ones... and... *Turanoceratops*. There just was little evidence to really test this.