Re: Sauropoda Necks

["Matthew Bonnan" <mbonnan@hotmail.com>]

Hi all and Happy New Year 2002!

Dan Varner writes:

   "Speaking of sauropod neck postures... If you haven't seen it yet,
check out Matt Bonnan's Camarasaurus reconstruction at:

       http://www.wiu.edu/users/mfb100/research.html

       It's quite different from what you're used to. Made me scrap a
painting that was nearly finished. DV"

While I am flattered that my sketch of the Camarasaurus skeleton is the 
source of excitement and discussion on the DinoList, I must stress that my 
dissertation research was on sauropod locomotion.  As such, that drawing was 
mainly meant to show, to the best of my artistic abilities, ideas expressed 
in my dissertation about locomotion in Camarasaurus.  The neck portion of 
that drawing is derived from ideas and pictures of both the Osborn and Mook 
1921 monograph and Parrish and Stevens's recent (1998) discussion at the SVP 
on the possibility of a more horizontal-necked Camarasaurus based on 
preliminary data.  I must emphasize that the neck was not drawn from primary 
osteological data, and was just an attempt to present a somewhat different 
view of Camarasaurus based on very preliminary data.  In other words, the 
neck position is speculative and should not be intepreted as an actual 
scientific restoration.  The restoration itself is based on a variety of 
sources, and should be taken as a sketch, not a scientific work.  I am glad 
people like it, however, and I very much appreciate the advertisement of my 
WIU website. =)  I think the jury is out right now on exactly what is going 
on with the Camarasaurus neck, anyway, I would take all restorations of such 
with appropriate caution.  Seeing as mine is speculative, it may very well 
be wrong.

Seeing as there has been another thread on sauropod neck posture, I will 
throw in a few brief comments.  First, Parrish, Stevens, and myself have 
begun a new collaboration to expand and improve the initial DinoMorph 
studies of the neck incoporating data from the shoulder girdles and 
forelimb.  We will be looking at a larger range of sauropod taxa, and 
Parrish has begun to look in more detail at the necks of Okapis, camels,  
etc., to strengthen the comparative nature of the new study.  My role will 
be more tied with forelimb functional morphology and how shoulder position 
effects the starting height of the cervical (neck) vertebral series.  I am 
very excited to be part of this research, and I hope we find some neat and 
unexpected things to report on.

I tend to agree with Tracy Ford that sauropod rearing may be, for the most 
part, a myth.  Perhaps some sauropods did rear bipedally, but the mechanics 
behind doing this have actually never been seriously investigator or broken 
down biomechanically.  Various researchers have pointed to certain 
anatomical structures as evidence of rearing (i.e., tall neural spines over 
the pelvis), but no one has ever demonstrated that such osteological 
features are correlated with rearing in extant animals that do.  Elephant 
rearing is very serious business for the elephant, and it is done very 
slowly and meticulously.  Elephants do not have a long beam-like neck that 
sticks out several meters from their body, they have a completely different 
pelvic and femoral arrangement, and they kind of squat back on their haunces 
when rearing.  If sauropods did rear, it must have been something very 
different, but again, we enter the realm of the speculative here.  Ray 
Wilhite is actually working on this problem now in his dissertation research 
at Louisiana State University, and his work may reveal some interesting 
results.  I am also interested in pursuing some of this, but my current 
focus is still related to the forelimb of sauropods which I feel is more 
interesting evolutionarily.

Well, happy new year everyone.  Great to see that sauropods can still hold 
their own on the DinoList against the theropods.  It seems the 
ornithischians, especially stegosaurs, get short shrift here, so I always 
feel sorry for 'em. =)

Thanks,

Matthew F. Bonnan, Ph.D.
Department of Biological Sciences
Western Illinois University
Macomb, IL 61455
(309) 298-2155
mbonnan@hotmail.com
MF-Bonnan@wiu.edu

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