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Re: BIRD CHARACTERISITICS



At 09:10 AM 12/20/97 PST, Matt Troutman wrote:

>     Fedducia and Martin both claim that the Maxberg specimen ( sadly it 
>was stolen a few years ago) had its metatarsals fused in a 
>proximo-distal pattern like enantiornithines ( or their "Sauriurae" ) 
>and in contrast to the disto-proximal pattern seen in Ornithurae birds. 
>I do not know that this claim can be proven.

Archie does have the proximal part of the metatarsus fused, as in Avimimus,
Elmisaurus, enantiornithines, etc.

>>        Now, add polarity back in. If archie's metatarsus is more 
>silimlar
>>to that of the Enantiornithes, how does it compare to that of a 
>suitable
>>outgroup (e.g. Troodontidae, Dromaeosauridae, etc.).

Neither troodontids nor dromaeosaurids as currently know have fused
metatarsi.  Basally, birds seem to fuse from the top down and reverse it
further up the tree.

>      Honestly I cannot make an imformed opinion on this subject other 
>than the metatarsus of dromaeosaurids is quite similiar to than of 
>Archaeopteryx and that I think Tom said somewhere that the metatarsus of 
>Hulsanpes is fused.

But I never said that Hulsanpes was a dromaeosaurid... :-)

>What pattern; proximal- distal or disto-proximal, is 
>not stated. ( Have any insights Tom?) 

The top is fused, the bottom unfused, if memory serves.

>     While we are on the subject , Iberomesornis, what is it? 
>Enatiornithine, ornithothoracine, something else?

Basal ornithothoracine, according to Chiappe and Sanz.

Thomas R. Holtz, Jr.
Vertebrate Paleontologist     Webpage: http://www.geol.umd.edu
Dept. of Geology              Email:th81@umail.umd.edu
University of Maryland        Phone:301-405-4084
College Park, MD  20742       Fax:  301-314-9661