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Re: Three New Neoceratopsians (Bagaceratopsidae Described)



Having just read the description of *Magnirostris* (thanks again, Marco), I need
to revise some details of my earlier discussion on the matter.

  First, I described the condition of the incipient horn cores as occuring on
the prefrontals; however, this occurs at the junction of the frontals and
postorbitals, which are fused, and expanded dorsolaterally, indicating
"horn-like" protuberances. Secondly, the authors described *Magnirostris* as a
member of Protoceratopsidae, including *Bagaceratops* in this group, implicating
their following of Sereno (2000) in synonymy of *Breviceratops* with
*Bagaceratops.* Presumably, You and Dong (2003) were not aware of these studies,
and it would appear that, while You and Dong do consider *Magnirostris*
particularly close to *Bagaceratops* as discussed in my other post,
Bagaceratopidae may actually be a junior synonym of Protoceratopsidae. If so,
then it seems likely that *Protoceratops* may be the outgroup to a clade
consisting of *Bagaceratops,* *Magnirostris,* and the two new Barun Goyot taxa.

  This set of relationships has other implications, including rapid variation in
a close-knit group: Bayan Mandahu is one of the Djadokhta-like localities, and
contains *Protoceratops* and *Magnirostris,* a "bagaceratopid." *Protoceratops*
is known from the Djadokhta and Barun Goyot, and most bagaceratopids from the
Barun Goyot, suggesting as relatively short period of time in which variation
among so-called "genera" came about. This also suggests that the main features
which distingish taxa, being in the shapes of the snout, nasal, and post-frontal
region and jugal, are directly implicated as feeding (snout) and
display/agonistic regions of the skull (cheek, nose, and frill), which in modern
animals show remarkable variation among closely-related species, as in the bok
and gazelle tribes of antelope. This has a lot of effect in regarding the
specializations of feeding for competition of niches, whereas display may have
been selected for for different reasons.

  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.

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