RE: Just what is the correct digital formula for birds and other theropods, anyway?

["Thomas R. Holtz, Jr." <tholtz@geol.umd.edu>]

> From: owner-DINOSAUR@usc.edu [mailto:owner-DINOSAUR@usc.edu]On Behalf Of
> Roberto Takata
>
> On 8/24/06, Thomas R. Holtz, Jr. <tholtz@geol.umd.edu> wrote:
> > Actually, the bigger issue with this is that one has to move away from 
> > Owenian 19th
> > Century, or even embryological 20th Century, style definitions of homology. 
> > Our growing
> > knowledge of the genetic, phylogenetic, embryological, and related 
> > processes by which
> > organisms are built are now showing that the same physical part of an 
> > organism (in this
> > case, the autopodium) can  go through several different "identity" 
> > assignments (identity
> > as an autopodium; identity as serially arranged digits; identity as 
> > particular
> > morphological structures; etc.).
>
> Say, like the antennapedia mutation? (Is it homologous to antenna or to leg?)
>

Good example. It is in the position of the antenna, but it clearly has the 
morphology of a leg. So is it a misplaced leg? Or a
misformed antenna? Or (probably closer to the "true" answer) is it both?

                Thomas R. Holtz, Jr.
        Senior Lecturer, Vertebrate Paleontology
Department of Geology           Director, Earth, Life & Time Program
University of Maryland          College Park Scholars
        Mailing Address:
                Building 237, Room 1117
                College Park, MD  20742

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