Re: Geographic Distribution of Deinonychosauria

[tholtz@geol.umd.edu]

>>  True, but the stages don't last so long that one cannot infer
>>  distributions of nonvolant taxa fairly well from knowledge of the
>>  topographical layout (particularly if taking into account
>>  phylogeny).
>
> Maastrichtian: 5 Ma, Campanian: 13 Ma...
>
> Many stages in the Jurassic are estimated to be about 4 Ma long, which
> is also the confidence interval on their start and end dates.

Myr, not Ma. Ma is for dates, not durations.

>>  Apart from that, one can assume that open seas/oceans are a barrier
>>  to dispersal until proven otherwise, and simply deal with the major
>>  land areas (i.e. as isolated by open sea and high mountains).
>
> That's where uncertainties in paleogeographic reconstructions come in.
> How much connection was there between South America and Antarctica and
> between Antarctica and India in the Cretaceous? For how long? What about
> Antarctica and Australia or Madagascar and India? Or India and Africa?
> Etc., blah, blah.

Or the patchwork quilt of terranes that is the Asian-North American
corridor...