Re: FEET OF EARLY BIRDS

["Larry Febo" <larryf@capital.net>]

-----Original Message-----
From: Thomas R. Holtz, Jr. <th81@umail.umd.edu>
To: larryf@capital.net <larryf@capital.net>
Cc: dinosaur@usc.edu <dinosaur@usc.edu>
Date: Tuesday, September 15, 1998 2:03 PM
Subject: Re: FEET OF EARLY BIRDS


>At 06:14 AM 9/15/98 -0400, Larry Febo wrote:
>
>>     So, I assume that the original statement,.. that the
>arctometatarsalian condition is " reversed " in archaeopteryx, and
>enantiornithine (sp),.. dosen`t imply that it is in the process of being
>undone, but that the condition, unlike the arctometatarsalian, has the
bones
>fused principally at the proximal end. The Ornithurae would, as implied by
>Feduccia, have the arctometatarsalian condition, and therefore shouldn`t be
>grouped with the other two.
>>
>
>NONE of these birds shows the arctometatarsalian condition, which doesn't
>have anything to do with fusion of the bones.
>
>In the arctometatarsalian condition, the central metatarsal (III) is
>wedge-shaped distally, and becomes a thing solid splint proximally.  The
>sides of the wedge meet buttressing surfaces of metatarsals II and IV.
>
>Now a few theropods with arctometatarsi DO have fusion (proximal -
>Elmisaurus and Avimimus), but so do some theropods without an
>arctometatarsus (Syntarsus, for example).
>
>In the case of birds, there is actual fusion of the bones, but not an
>arctometatarsus.
>
>Hope this helps.
>
>Thomas R. Holtz, Jr.
>Vertebrate Paleontologist     Webpage: http://www.geol.umd.edu
>Dept. of Geology              Email:tholtz@geol.umd.edu
>University of Maryland        Phone:301-405-4084
>College Park, MD  20742       Fax:  301-314-9661
>

     OOps again! Sorry for putting words into Feduccias mouth, actually he
never mentions the term "arctometatarsal" at all. I suspected when I wrote
that post that there might not be a direct link between that term and actual
fusion of the bones, but figured someone would correct me if wrong.
Actually, I should have looked into "Encyclopedia of Dinosaurs" (which I
previously lauded) first. There I would certainly have found a quite
thorough description of the term by a quite competent authority on the
subject! PS, It really is a good book ,...if one bothers to open the cover!