neck length of dinosaur ancestor -Forwarded

[JNorton@xxxxxxxxxxxxxxx]

** Reply Requested by 2/7/2106 (Sunday) **

        Date:  11/03/1995   3:43 pm  (Friday)  
        From:  James Norton
          To:  Vertebrate Paleontology Group
     Subject:  neck length of dinosaur ancestor


A question from an amateur:

Is it possible that the relatively long neck present in the earliest bipedal
dinosaur ancestor developed in conjunction with the bipedalism?  My
concept is that a bipedal predator would have a better chance of
grabbing prey during pursuit if the two grasping limbs and the neck and
head could combine to cover a full 360 degree circle, viewing the animal
head-on.  The forelimbs of early theropods seem to be able to reach the
ground, and the necks seem at least as long as the forelimbs
themselves.  If each of the three covered one-third of the circle, the
creature would be able to snag a fleeing prey regardless of the direction
in which it moved.  In a running animal, the ability to grasp a prey with
"hands" or mouth within a certain radius would define a "cylinder" within
which predation would be effective.

I'm trying to assess the survival value of the relatively long necks
of predatory dinosaurs, and whether a commitment to a long neck early
in dinosaur development required other forms of commitment with the
ventilatory/respiratory system.

Any thoughts, comments, references would be appreciated.

James M. Norton, Ph.D.
University of New England
Biddeford, ME  04005
phone: (207)283-0171
fax: (207)283-3249
email: jnorton@mailbox.une.edu