Re: Revising Hou et al, 96 (woo-o-o-o-o-o-o doggy!)

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

David Marjanovic (david.marjanovic@gmx.at) wrote:

<Oh, let me continue: Entelodonts! :-)>

  Okay, yes, there are juvenile archaeotheriids (*Archaeotherium*) that
have yet to be described that also have serrations on parts of their
canines, but these are quickly worn away. More research to come on these
beauties, can't believe I forgot about them ... Darren and I were drooling
over these a year and a half ago.... Both are neomorphic, and appear to be
responses to predation. This is not typical of mammals, as it is for
theropods and archosaurs in general, and it is considerable that their
appearance in mammals is functionally linked to canines modified with a
cutting edge. The retained cutting edge and arboreal specialization of
many maniraptorans takes this out of context. I think the basal condition
of maniraptoran teeth is serrated (*Ornitholestes*, *Protarchaeopteryx*,
Segnosauria, Dromaeosauridae, Troodontidae [not including
*Byronosaurus*?]), plus it's outgroups. Teeth morphotypes may transform
from a basal constriction in some maniraptorans to broad-based teeth, as
supported by recent analysis, as the only broad-based--toothed
maniraptorans are dromaeosaurids, but the presence of serrations as a
theropod plesiomorphy seems less shakable. Not sure.

  Cheers,

=====
Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

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