[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

RE: sauropod lung collapse



W. F. Zimmerman (wfz@wfzimmerman.com) wrote:

<This doesn't clinch the case, does it?   Plenty of large animals like
hippopotamuses and, yes, whales manage to spend quite a bit of time deep under
water without having collapsed lungs and do their breathing when they're safely
above water.>

  As well as crocs, sirenians, etc.

  A decent test may be to study the morphology of the ribs for continuous
submersers like aquatic species like sirenians and dolphins versus those of
temporary submersers like hippos and crocs, and rare submersers like horses,
etc., and determine the variabilities. The presence of dense bone to counteract
bouyancy, rounded ribs to counter external pressure, a round thoracic cavity
rather than "slab-sided" for equalization of pressure around the rib case, etc.


  Since we are having difficulty reconstructing the actual breathing system in
sauropods due to some interesting consdiderations of the involvement of the
pneumatic system of the vertebrae from the sacrum up to the anterior neck, we
may have to use only the skeletal features present and their capacity to infer
soft-tissue, and compare these to sauropods. But as Alexander noted, the limb
system of sauropods appears to be terrestrial based, and is adapted to bearing
heavy loads vertically, rather than semi-sprawled, such as one might expect if
the animal were walking around with its full weight on its feet, also perhaps
without any mitigating effects like bouyancy in water, etc.

  Cheers,

Jaime A. Headden

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

__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com