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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.