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

Re: Baja-ing Dinosaurs



>> Haven't Triceratops' elbows been shown to  stick out not nearly as far
>> previously thought (or at all if you ask Uncle Bob)?  I still don't get t=
he
>> idea of dune-buggy suspension; I guess I'd have to take a better look at =
a
>> dune-buggy...
>
>     It has been shown recently that ceratopsian forelimbs really did=20
>sprawl.  I think the reason was that if you=20
>give the forelimbs an upright posture like Bakker did, you are seperating=
 the=20
>scaplula-corocoids instead of them being in contact with each other like=20
>they are supposed to be.  If I'm not getting my studies crossed, it was=20
>done playing around with Torosaurus bones.  I can't remember who was=20
>involved.  DId Ostrom have something to do with it? =20
>

Yes.  In 1990, Rolf Johnson and Ostrom did this study with a fiberglass=
 replica of their Torosaurus forlimb and shoulder bones.  After installing=
 flexible elastic to simulate muscles, they placed the forlimb in each=
 possible position: sprawling, semi-erect, and fully erect.  From this=
 manipulation, they have shown that the forlimb simply couldn't function=
 smoothly if it was fully erect.  They found that a semi-erect to sprawling=
 posture is most effective.

As far as the trackway data; Bruce Erickson (vert paleo for Science Museum=
 of Minnesota) has reconstructed the trackway that their sprawling=
 Triceratops would've left.  Suprisingly, the dimensions of this trackway=
 match those described in Lockley & Hunt (Nino); so sprawling posture in=
 ceratopians is still a viable possibility.

Rob

***
The pun is the lowest form of humor
     --Unless you thought of it first!!!