Re: sauropod nostrils

[Betty Cunningham <bettyc@flyinggoat.com>]

heh 
if dinosaurs 'sneezed' to rid excess salts like some reptiles and birds
do now
....and some sauropods had nostrils on the top side of the head...
how would sauropods with nostrils-on-top have kept the snot from going
back in?
Or from smearing snot all over their heads, for that matter? 

-Betty Cunningham
(humming that old Johnny Mathis tune, SNOT GETS IN YOUR EYES)

"k. clay" wrote:
> 2) For nasal respiration to occur, oxygen would have to diffuse through
> specialized respiratory epithelium in the nose.  This would have to be
> very thin, very moist, and very vascular. Human alveoli are less than
> 0.2 microns in diameter; frogs (which can get about half their needed
> gas exchange through their highly vascularized skin) have an epidermis
> only 5 to 8 cell layers thick.  The problem for sauropod nostrils would
> be drying out.  Oxygen is only utilized by biological forms when
> dissolved.  Lung alveoli are coated with a small layer of water, and are
> kept warm (warm air holds more moisture than cold air) and placed
> internally to prevent evaporation.  Frogs are either restricted to moist
> microhabitats or have behavioral adaptaions (burrowing underground) to
> avoid dessication. Nostrils on the top of the head with vascular, moist
> epithilium would be at great risk for dehydration.


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Flying Goat Graphics
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