Re: Horn of plenty

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

> From: Pluto77189@aol.com

> styracosaurus's spiky frill is actually in a better place for intraspecific 
> fighting than the nose horn.  I do >not think they had necks as flexible as 
> modern herd animals necessary to use them as such.  Look at >ibex, oryx and 
> other gazelle-looking ungulates, their horns point backwards too.  When 
> locking horns, >the animals lower their heads and the spike point towards 
> each other, and the fight ensues.

I'm not so sure about that.  The _Styracosaurus_ skull that I'm thinking 
about (the type), at least, has it's parietosquamosal spikes oriented in a 
dorsolateral way (moreso so lateral than dorsal).  As such, if the head was 
pointed downward, the spikes would in turn project almost vertically, and I 
don't think they could lock with another set of spikes with any ease 
whatsoever.

> As far as I know, there have been NO triceratops discovered with a 
> significant difference in horn size >indicative of sexual dimorphisim.

Indeed, horn size varies a lot within ceratopsian species and does not 
necessarily seems to indicate sexual dimorphism.  The angles those horns 
make with respect to the skull, on the other hand, >may< help to distinguish 
the sexes.

Jordan Mallon

Undergraduate Student, Carleton University
Vertebrate Paleontology & Paleoecology

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

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