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Re: "Oxygen Helped Mammals Grow, Study Finds"

"    Hengst and others (1993, 1996) demonstrated that a large long necked
sauropod suchas the Tithonian

and/or Kimmeridgian...

_Apatosaurus_ required an oxygen content in
the atmosphere of about 35% to function at any level above a very slow walk,
slower than the rates deducted from trackways.

Hengst et al. showed nothing except their capability for impressive oversight. They assumed a lizard-style lung or something. They didn't even mention the possibility of a bird-type lung! I'm sure even a crocodilian lung (cross-current gas exchange, ventilation by moving the liver) would have given less reality-free results (if we ignore for a minute the absence of gastralia and pubic mobility in sauropods).

Our measured levels of [B]arremian and Aptian oxygen are 28%
and 29% respectively. It thus is not very surprising that our only
surviving Aptian sauropods are both small, and short-necked, clearly
adaptations to these low Early Cretaceous oxygen levels.

Long live *Sauroposeidon*...


Was there such a thing...?


Hengst has shown that Dinosaurs could not venilate their lungs as easily
as Birds or Mammals (Hengst et al '93, '96).

By means of at least spiral reasoning, yes.

*    Mammals and Birds only require 7 breaths to completely
replace the air in their lungs.

I'd bet money that birds require fewer than mammals! Birds have smaller lungs and larger tidal volume.

   Barremian                                130 mya             28%
   Aptian                                     115 mya             29%
   Cenomanian                               95 mya             35%
   Turonian                                    88 mya             33%
   Judith River Formation                  75 mya             35%
   Basal Hell Creek                           70 mya             35%
   Hell Creek (Maastrictian)               68 mya             35%
   Top-most Hell Creek                    65.2 mya          31%

AFTER K/T Boundary 65 mya 29%

Is there so much Cretaceous and Paleocene amber???

Interesting how the authors use "secular" -- apparently for "long-term".

Latin saeculum = "century" or "era". The religious sense is derived from the meaning "not eternal".