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


On Wed, 27 Mar 1996 GSP1954@aol.com wrote:
> 3 - It is difficult to see why the sled chevrons of diplodocids were involved
> in supporting the tail when they are on the underside of the tail. The
> primary support strutures should be dorsally located where they work under
> tension, not ventrally where they are under compression. Nor does tail
> support explain the presence of sled chevrons in stump tailed ground slothes.
> A better explanation for sled chevrons in sauropods and slothes is as
> protection for the underside of the tail during habitual rearing. 

        I'm having doubts after I took a close look at a couple of your 
illustrations the other night. On Shunosaurus, the forked chevrons go all
the way out to the tip, where they wouldn't be of a lot of use- there 
wouldn't be much pressure on the tail out there during rearing. On 
Kentrosaurus, they go all the way up to the first chevron, too far 
forward to be in contact with the ground. They are absent in 
Stegosaurus, who was also presumably a tripod-feeder. On Euoplocephalus 
they are present on the distal portion. Looking in the local museum, they 
are also present on the skeleton of some african critter called a "moon 
rat". I don't know what a moon-rat is or what the heck it uses its tail 
for, if anything. 

        nick L.