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re:extinction events in Mesozoic
To underscore Thomas Holtz's comments:
I'm not sure that sauropods readdy we(try really went) extinct in the Maastricht
Ve noted before, there are a slew (slough?) of sauropod remains
in the Maastrichtian of West Texas, and I'm not convinced that they re-emnigrate
re-emigrated from S. America. The same taxa are common in N. Mexico and
to a lesser extent in Wyoming. Thus sauropod extinction is greatly
There was apparently a major late Triassic event among a wide variety
of tetrapods, but I'm not the one to tabulate taxa involved there. As
I see the record, nothing else noteworthy occurred during the Mesozoic
except, of course, the K/T thoing. Indeed, the *lack* of a significant
mass extinction event post end-Triassic and prior to the K/T is
noteworthy, since that contains ca 180 Million years of tranquility.
In fact, to beat sauropods to death, they have a funny way of being
around with few body fossils. For example, in the Late Cretaceoius
of eastern US we have a single set of caudal veretbrae from North Carolina
(_Hypsibema crassicaudata_), and a single, isolated caudal from NJ. Period.
Are we to assume a single critter wandered or swam over from Texas or
New Mexico? More likjely thie (awful typos today:() their habitat
was somehow cryptic: perhaps piedmont of Appalachioans or something
of the sort. Ditto for the Paluxy beds: tracks mean trackmakers,
and there was clewarly a big population.
How do 10+tonne animals disappeart so easily from the record?