RE: Evolution of tyrannosauroid bite power

[ptnorton <ptnorton@suscom-maine.net>]

Tom Holtz wrote on Thu, 20 Dec 2007 08:25:19 -0500

> Well, of course, and I think everyone working on this would agree exactly
> with that scenario.
>
> But a biomechanical analysis must needs focus on one particular part of the
> organism, and later be integrated into other comparable systems.

That is the traditional approach, but methods for analyzing the motion of 
complex (i.e., multi-part) mechanical *systems* are being developed that 
show a lot of promise for analyzing biomechanical systems. The 
methodological problem in analyzing each part of an animal separately is 
that the parts are not independent of one another.  Analyzing them as a 
complex biomechanical system with multiple dependent parts is an effort to 
get away from that problem. For an example from mechanics, see Hong and 
Cipra's 2003 paper illustrating a method to analyze the motion of complex 
cable-pulley systems, which can be found on-line at 
http://www.me.vt.edu/romela/RoMeLa/Publications_files/JMD2003_CablePulley.pdf. 
It's probably not the best example, but it's useful for illustrating the 
distinction I was trying to make. It seems to me that the relationship 
between arm size and bite power, or arm strength and hip strength, offer 
some real potential for using this type of systems analysis.

PTJN


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