Re: marginal differences

["Jordan Mallon" <j_mallon@hotmail.com>]

> From: zone65 <zone65@telstra.com>

> How do the two species of Triceratops differ? Again, it's not just a matter 
> of splitting hairs?

Forster (1996) characterized _Triceratops horridus_ as having a longer 
rostrum, open postfrontal fontanelle, and relatively long supraorbital 
horncores.  She also characterized _T. prosus_ as having a short rostrum, 
closed postfrontal fontanelle, and relatively short supraorbital horncores.  
Lehman (1998) disagrees with Forster's 2 species conclusion, however, as he 
finds the differing morphs tend to fall within a "gradational spectrum of 
variation."

Jordan Mallon

Undergraduate Student, Carleton University
Vertebrate Paleontology & Paleoecology

Paleoart website: http://www.geocities.com/paleoportfolio/
AIM: jslice mallon

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