Re: Orbital bars

[Waylon Rowley <whte_rbt_obj@yahoo.com>]

Jordan Mallon wrote:

> The topic of orbital bars has recently come up on a
> message board I frequent.  I understand _T. rex_ had
> them, as did_Carnotaurus_, and maybe a few others 
> that I'm not aware of.

I probably don't have a complete list either, but I
know that _Acrocanthosaurus_, _Carcharodontosaurus_,
_Giganotosaurus_, _Abelisaurus_, _Majungatholus_, and
_Albertosaurus_ can be added. In fact, I remember
seeing a specimen of _Albertosaurus_ where it looked
like the suborbital bar had been shifted far ventrally
and contacted the base of the lacrimal. Pretty
extreme.    

> But what's the significance of these structures?  
> Have any suggestions been put forth as to why they 
> might have arisen?

I believe someone once suggested that they helped
support the eyeball. The suborbital ligaments also
attach there. Hope I've been of help.

Cheers,
Waylon Rowley

"My train of thought has become a runaway caboose."
   

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