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AVIMIMIDS & MANIRAPTORA SENSU HOLTZ



AVIMIMIDS

If the hindlimb of _Avimimus_ really is that of another theropod, whether
avialian or not, where does that leave other avimimus-like material? The
_Kakuru_ metatarsal has been compared to that of _Avimimus_ (by Ralph Molnar I
think), well if the whole of A's hindlimb might be from an elmisaur or an
avialian, where does that leave _Kakuru_? Might it be (very ambiguous) evidence
of a Cretaceous ozzie flightless bird? I have read of more avimimus-like
material coming from both China and Canada. Was any of this more material from
_Avimimus portentosus_, or are more species involved? Or is the stuff indet?

MANIRAPTORA SENSU HOLTZ

Gauthier originally defined maniraptorans as 'all coelurosaurs closer to birds
than to ornithomimosaurs'. This was because he envisioned ornithomimosaurs
diverging first right? The subsequent lineage, crowned by avialians, would
therefore be the Maniraptora. Right? But Dr. Holtz' more recent analysis sees
the dromaeosaurid + avialian clade diverging before the lineage including the
ornithomimosaurs. This now means that all post - drom + avialian coelurosaurs
are closer to ornithomimosaurs - it would therefore create a paraphyletic
Maniraptora if we retained Gauthier's allocations. The Holtz solution to this
was to redefine Maniraptora as the node shared by the drom + avialian clade and
the clade including ornithomimosaurs (therefore ornithomimosaurs and
tyrannosaurs are maniraptorans). Right? This effectively changes the definition
of the maniraptorans entirely and, as revealed in a recent posting, Dr. Holtz
now plans to amend this (Maniraptora would be the clade including droms and
avialians, the node at which maniraptorans and later coelurosaurs diverged would
now require a new name). BUT, in that definitive study, the new definition and
allocation of the Maniraptora is stated clearly. Why must this be changed? Would
people rather prefer Gauthier's original meaning of Maniraptora? Can someone
tell me (sorry to be such a pain Dr. Holtz).

DARREN "fluidity" NAISH