Re: Sapeornis chaoyangensis [gen. et] sp. nov.

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

David Marjanovic (david.marjanovic@gmx.at) wrote, in reply to Gerrit
Hanenburg (G.Hanenburg@inter.NL.net):

Gerrit:
<<It shares several primitive features with Archaeopteryx and
dromaeosaurs, such as a short and nonstrut-like coracoid, well developed
manual digit I, a fibula reaching the distal end of the tarsal joint,>>

David:
<Unlike Avimimus, apparently Yandangornis and Pygostylia. Teaches one to
be careful when assuming synapomorphies instead of convergences (Holtz
mantra number...).>

  *Avimimus* most certainly can be present shown from the published PIN
specimens to have both a "normal" coracoid, with an everted ventral
margin, but not strut-like, and with a fibula that descends to the tarsus,
based on the presence of a fused distal fibular shaft fused to both
calcaneum and tibia. Such fusion is seen in mammals whose lower limbs
undergo more typical stress than normal "walkers" or "joggers". Most
mammals have such ankles, but this is considered an advanced running,
i.e., hypercursorial adaptation. Hmmmm...

=====
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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