Fwd: Re: Theropod traps

[tidwell@ix.netcom.com (Virginia Tidwell)]

Neil wrote:
I love this idea.  Has anyone attempted to sex the bones of 
carnivores in a mass kill?  If it is a family group, some  
carnivores tend to have large female:male ratios.  Males are also 
frequently solitary and the females group together.  

Neil

One of the examples in question was the coelophysis quarry at Ghost 
Ranch, NM.  Here a very large number or specimens of coelophysis are 
found in both articulated and disarticulated states.  Individuals of 
all ages and sizes are represented.  There does seem to be some 
dimorphism exhibited by the adults - usually thought to be related to 
sex.  There is a more robust version and a gracile version of the same 
species of coelophysis. I don't know of any study to compare the ratio 
of robust to gracile forms - perhaps because much of the material that 
was original quarried has not been fully prepared as yet.  It is spread 
out all over the country in huge blocks, being worked on by several 
different institutions.  So we don't know if coelos lived in harems or 
some other form of group.  The Ghost Ranch mass death site has not been 
adequetly explained as far as I am aware.  An excellent reference book 
is Colberts Dinosaurs of Ghost Ranch.
         Hope this helped
            Virginia Tidwell