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re: Tanystropheus neck posture



At 07.44 24/10/02 -0500, you wrote:
Maybe Tanystropheus wasn't marine.

I just took a look at Wild 1973 and note that in exemplar q,

err.. in Wild 1973 exemplar q is an isolated skull and neck, thus you probably refer to another specimen, but which one? exemplar m looks like having a crack just there, exemplar k show anterior dorsals but to my eyes the angle is between the last cervical and the first dorsal, exemplar a, the one figured also in the site shows a some angle between anterior dorsals.


  To my eye there is no neck contraction, but rather it
appears to have a camarasaur-like setup.
I can check it on the cast of specimen a...

Just a wild hypothesis, but what if Tanystropheus fed on arboreal
diapsids, like longisquamids and basal pterosaurs, by standing at the
base of trees and searching the boughs for prey?  The clincher is the
giant penile bones would make great bases for a tripodal posture.

Mmm... the Gerenuk (if I remember the correct name) is an antelope with a long neck that adopts bipedal stance to browse high foliage, keeping steady by grappling trees with forelimbs. The posture is a bit awkward but apparently it works. However the main difference is that foliage doesn't rush away when the head come close it is much simpler to pick up also in a static position. a small swift animal is much harder to be catched in that way, I suspect. Foliage is abundant and you have not to move from a tree to another too often, thus this feeding strategy is rewarding for the antelope. A predator should move much more frequently, especially if catching a small prey it puts all the neighbours in alarm and they flee away. And foliage, small branches etc. may be a serious obstacle to catch those preys. Much better to be small or sneaky for this task.
And don't forget, apparently the clincher or whatever they are, are present only in half of larger known specimens...

All the best,

                                Silvio






_ "When they hear of the Way, The highest minds hurry up to practice it; The average minds think about it They sometimes feel it real and sometimes not; The lowest minds laugh at it. If they did not laugh at it, It would not be the Way."

                                (Lao Tzu)


Silvio Renesto

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