Re: Nemegtian tyrannosaurs

["Jaime A. Headden" <qilongia@yahoo.com>]

Tim Donovan (uwrk@yahoo.com) wrote:

<The more heavily forested Hell Creek was probably more conducive to the
survival of tyrannosaur juveniles, which tended to overheat more quickly
due to their lesser body mass.>

  I think this interpretation is error, based on the nature of the Hell
Creek sedimentology, focusing on highland and savannah-type regions, with
low tree density. However, the "bayou"-like environments of the Nemegt and
Dinosaur Park/Judith River Formations are much more heavily wooded, not
the other way around. The Nemegt was not at all a "desert-like"
environment 75mya, but very, very wet. The idea that it was drier than the
Hell Creek is ridiculous, no matter the posture of rigor in *T. bataar*
specimens found there, which would be expected in any _warm_ environment,
not just a dry one (not the presence of rigor-stricken birds in
Lagerstätten).

  Incidentally, the Two Medicince is almost certainly the same formation
as the Judith River Formation, separated almost entirely by the Montana
state line.

  Cheers,

=====
Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)

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