Re: Gallery and Commentary for Copenhagen Mamenchisaurus

[DinoBoyGraphics@aol.com]

Nick said:

>>>Just playing Devil's advocate here (snip), but the vast majority of grazers 
>>>today are mammals, with big, heavy jaws, teeth, and brains that sauropods 
>>>didn't have to deal with.<<<

Despite this, giraffes have long necks, so apparently mammals can evolve them 
under the proper selection regime.  Also, many dinosaur groups (ornithopods, 
ceratopsians) which were certainly grazers or low browsers follow the same rule 
on neck length, and while ceratopsians have big heads, not all ornithopods do.

Also, Mike Taylor said:

>>>my impression with _Camarasaurus_ is that it is widely perceived as being 
>>>shorter-necked than it really is due to the preponderance of sub-adult 
>>>specimens<<<

I can't speak to the publics impression of camarasaur neck length, but we have 
two at the Wyoming Dinosaur Center, and the neck is not much longer than is 
needed to reach the ground (especially with the difficulty in lowering the neck 
with the upward oriented cervico-dorsal region...).  Not that the anatomy 
supports (in this case) grazing, but the energetics wouldn'tbe too unfavorable.

>>>positive allometry on neck length would be evidence supporting a sexual 
>>>display interpretation of the neck, but I am pretty determined to resist 
>>>that as it's such a pathetic cop-out :-)<<<

I agree, though at least it is energetically plausible.


Scott Hartman
Zoology & Physiology
University of Wyoming
Laramie, WY 82070

(307) 742-3799