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Dinosaur Genera List corrections #67

Dinogeorge writes:
>Novas classifies _Patagonykus_ in Alvarezsauridae and in turn classifies
>Alvarezsauridae in Avialae as a "metornithine" bird higher up the cladogram
>than _Archaeopteryx_. Unfortunately, his character matrix contains so many
>reversals and unknowns as to make the analysis dubious. But based on his
        This is nonsensical.  If the character matrix supported
classifcation of mony as an arctomet (just for example), it would *still*
contain a similar number of unknowns (actually, probably more), and a whole
nother lot of reversals and other homoplasies.  (Not that the matrix does
not contain reversals, the phylogenetic hypothesis generated from the matrix
does.)  In fact, it should contain *more* homoplasies, as the hypothesis
generated in the paper assumes a *minimal ammount of homoplasies* (because
it is a cladistic analysis).  Thus, any other tree should include a
*greater* number of homoplasies.  So what you're saying is nonsense.
        Also, I should really like to see you take that character matrix and
eliminate some of the unknowns.  You can't.  Why?  Because we just don't
know them.  We have to do science based on *evidence*.  This is what Novas
has done.

>description, I would agree that _Mononykus_ and _Patagonykus_ are related
>(they're just not particularly closely related to _Alvarezsaurus_) though I
>don't see the relationship as being particularly close.
        Not relevant.  What *is* relevant is whether or not they are more
closley related to other taxa in the study.

>In their statement, the authors of the paper effectively inform us that
>unless someone else creates a more detailed cladogram that shows a different
>set of relationships among the taxa, their cladogram must stand.
        John Hutchinson has nipped this in the bud.  Let me add, where is
*your* analysis, George?  :)

>Thus, it is
>up to the functional analysts to explain how, for example, _Mononykus_
>redeveloped a dinosaur-like tail with elongate haemal arches from an avialan
>tail like that of _Archaeopteryx_, 
        Yes, "up to the functional analysts", *not* the taxonomists.

| Jonathan R. Wagner                    "You can clade if you want to,     |
| Department of Geosciences              You can leave your friends behind |
| Texas Tech University                  Because your friends don't clade  |
| Lubbock, TX 79409                               and if they don't clade, |
|       *** wagner@ttu.edu ***           Then they're no friends of mine." |
|           Web Page:  http://faraday.clas.virginia.edu/~jrw6f             |