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Re: Temp in Cretaceous



In a message dated 95-10-13 11:40:35 EDT, Thomas_R_HOLTZ@umail.umd.edu (th81)
writes:

>The shallow seas were probably the major factor in keeping more stable, less
>vairable continental temps. during the later Mesozoic.  The middle
>Cretaceous is one of the greatest oceanic highstands in the last 500 million
>years, and even the Late Cretaceous was fairly flooded.
>
>

So it puzzles me why the Bering Strait is said to have opened and closed so
often to let all those dinosaurs cross over from Asia to North America and
vice versa, if the sea level was so high. I think the Bering land bridge was
mostly unavailable during the Late Cretaceous because of the high sea level,
which means the Mongolian and North American dinos of that time were not as
closely related as we might think. Same families, yes; same genera, very
doubtful, even in the case of _Saurolophus osborni_ and _?Saurolophus
angustirostris_. Do you know of any references documenting geological
evidence that the Bering land bridge was open (i.e., above sea level) during
the Mesozoic after the Campanian?

G.O.