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Re: Coeluridae as a Wastebasket for Coelurosaurs



>      As for wastebaskets, Mike Keesey splits his up into a series of
> separate "incertae sedis" wastebaskets, while I prefer to combine several
of
> them into one larger organized paraphyletic "wastebasket" (Coeluridae).  I
> still think there is more than one way to skin a cat, and Mike's is just
> different (not necessarily better).  Since I don't recognize as many
formal
> taxa, I have fewer wastebaskets, but I clearly mark them as paraphyletic.

What I have meant by wastebasket are things like Thecodontia in the 1960s --
assemblages of basal taxa of which no one knows how they're related to each
other and related groups. (Remember how often it was suggested that
sauropods might have been descended from Rauisuchia because both were
quadrupedal and had vertical legs -- urgh...)

Your Coeluridae is somewhat different, because you do give an idea on how
the cladogram that lies in it might look like. However, the evidence for
this -- or practically any other -- cladogram of basal coelurosaurs is so
weak that -- don't take it personal -- I'll continue to call your Coeluridae
a wastebasket like good old Thecodontia.

> On the other hand, Lophotrochozoa is such a wastebasket that I won't
> recognize it even informally, and yet it is being passed off as a
> holophyletic clade and uncritically accepted as such by most biologists

Like others on this list and the PhyloCode mailing list, I'd be very
interested to see evidence for that (on- or, perhaps preferably, offlist).

> (which I think is far more damaging than any well-organized paraphyletic
> assemblage such as Coeleuridae).

As I said above, I think your Coeluridae is better organized than is
actually possible.

> Keeping them as two separate
> orders gives me more flexibility just in case Saurischiformes is
> paraphyletic rather than holophyletic.

Saurischia has a definition, and everyone uses it now -- how can it possibly
be paraphyletic? (Even without definition, HP Jaime A. Headden has cited
lots of good evidence that it is holophyletic.)

> Remember that Sereno

and the rest of the world, well, nearly :-)

> had quite a nice list of
> synapomorphies for Ornithodira, and yet the idea of this as an exclusive
> clade for pterosaurs, dinosauromorphs, and Scleromochlus, is being rapidly
> abandoned as Dave Peters viewpoint is being overwhelmingly accepted.

I still can't -- how can the air sac system evolve twice?

> This
> is definitely one of the major reasons I oppose cladistically finely
split,
> intermediate taxa like Ornithodira.

Are broadly lumped, formal families like Coeluridae... :-/ I personally
would, if I'd use the Linnean or your system, never have made up such a
family, rather several smaller ones like Dryptosauridae, Ornitholestidae,
Compsognathidae etc., plus lots of "plesia". (Cladists who reject monotypic
taxa are exactly doing the latter.)

> For more on that I would suggest reading
> again Michael Benton's article in Biological Reviews last November, which
> has been selectively criticized while ignoring the more important valid
> points that it makes.

When I look at
http://www.cmnh.org/fun/dinosaur-archive/2001Feb/msg00526.html (and IIRC the
discussions on the PhyloCode mailing list), and IIRC what I have remembered
from reading it online, then I wonder what that more important valid point
is...