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


Besides, Coombs did not explain why the anterior caudal 
>ribs are so elongated if not for muscles to swing the tail from side to 
>side. There is nothing in the anatomy that precludes the animal 
>crouching with its butt in the air to swing the club. The amount of 
>movement between each vertebrae does not have to be great, but the 
>effects will be cumulative down the tail to the club handle (fused 
>caudals). As for the idea of mimicry, only in Euoplocephalus is the 
>club spherical - i.e., skull like. In most other ankylosaurids, the 
>club is elongated and low in profile, and sometimes wide; these 
>certainly do not look remotely like a skull (or head). The idea of 
>Tony's was interesting and I thought it worth suggesting - afterall 
>that is how science grows.
>Kenneth Carpenter

Actually this suggests that I may have been partly wrong in my contribution
to this debate the last time round, by suggesting that the chief problem
with the mimicry hypothesis was that it was untestable.  If I understand Dr.
Carpenter correctly, the mimicry theory should predict greater vertical
flexibility in the tail-trunk system (or at least a greater ability to hoist
the club in the air even if that meant tilting the whole vertebral column by
lowering the front end) than horizontal.  It would seem that this prediction
is not borne out., which makes the mimicry idea a failed theory but (despite
my earlier argument) a good hypothesis.

A question; would the degree of horizontal vs vertical movement suggest that
an ankylosaur would have been aiming mainly at an attacker's legs (with, I
suppose, the aim of throwing it off balance) rather than generally flailing
away at it (in which case rotation in three dimensions would be more useful)?
Ronald I. Orenstein                           Phone: (905) 820-7886 (home)
International Wildlife Coalition              Fax/Modem: (905) 569-0116 (home)
Home: 1825 Shady Creek Court                  Messages: (416) 368-4661
Mississauga, Ontario, Canada L5L 3W2          Internet: ornstn@inforamp.net
Office: 130 Adelaide Street W., Suite 1940    
Toronto, Ontario Canada M5H 3P5