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RE: Geographic Distribution of Maniraptora

> Some things to note:
> * Better to use shorter time slices than whole
> Periods. After all, the
> Cretaceous is far longer than the entire Cenozoic
> Era.
> * Paleoreconstructions are just hypotheses, and so
> are subject to change and
> uncertainty.

A good thing to add would be marking the extent of
uncertainty due to glacial/interglacial cycles, which
planetary mechanics will enforce no matter if the
atmospheric composition says greenhouse or icehouse.

Even during the Cretaceous, the evidence supposts the
notion of brief (some Ma) cold spells during which
there was significant mountain, North Pole, interior
Antarctic glaciation. For biogeography, say for the
Turgai region the European archipelago, the associated
sea level changes have significant consequences.

But generally, with a good background knowledge you
can at least mentally map a lot. Physical geography is
probably more useful than geology here.



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