Re: gastroliths (was Re:Giant carnivorous geese)

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

Steve Brusatte (dinoland@lycos.com) wrote:

<Certainly.  I wish I knew a) what _Proteles_ potential ancestors were, b)
their feeding style, and c) if they possessed gastroliths.  It would
certainly be interesting if _Proteles_ had a bone-crushing ancestor and
co-opted gastroliths to crush chitinous insect exoskeletons.>

  *Proteles* is a basal hyaenid, a proteline; for something concise and
recent, you can read Joeckel, 1998.

  Joeckel, R.M. 1998. Unique frontal sinuses in fossil and living
Hyaenidae (Mammalia, Carnivora): Description and interpretation. _Journal
of Vertebrate Paleontology_ 18 (3): 627-639.

  There were likely more toothy protelines, but these would have resembled
primitive hyaenids, as well. Hyaenid phylogeny has received some recent
work including in _American Museum Novitates_ but currently there are some
distinct hyaenines, a proteline, and a bunch of indistinct hyaenids that
look like hyaenines generally. *Proteles* is very specialized cranial, and
generally feeds in the manner of aardvarks, by digging in to termite
mounds and "snuffling" around for insects and using its narrow snout and
long tongue to procur them. Reduction of dentition broadens the palatal
area, as well as posterior extension of the plate behind the last molar,
are conclusive to a palatal-crushing mechanisms. The exoskeletons are
consumed and are crushed by gastroliths, which is a feature seen in other
insect feeders, mainly birds, or those animals with superior gizzard-like
organs, as in anteaters. However, primary processing is in the mouth,
unlike other formicivorous animals sans birds, and this is the primary
reason for preteline uniqueness.

  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.

__________________________________________________
Do You Yahoo!?
Yahoo! Finance - Get real-time stock quotes
http://finance.yahoo.com