RE: Young rex, triceratops...

["Jaime A. Headden" <qilongia@yahoo.com>]

Tom Holtz (tholtz@geol.umd.edu) wrote:

<Although Horner didn't state it as such, I noted at the talk that several of
the features (especially concerning development of the nasal horn and
orientation of the postorbital horns) that distinguished subadult from adult
_Triceratops_ are ALSO traits used to distinguish _Diceratops_ from
_Triceratops_. So regardless of whether _Diceratops_ is its own genus (or
species of _Triceratops_) or not, the type was likely not fully grown.>

  It is also possible that *Diceratops* is a paedomorphic form of
*Triceratops*, retaining the juvenile horn orientation of the larger species.
Something similar to the juvenile teeth of tyrannosaurines versus the
incrassate adult teeth of adult albertosaurines/*Albertosaurus* (sensu Carr et
al.) and other non-tyrannosaurines.

  Cheers,

Jaime A. Headden

"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)


                
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