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re: bat/ptero wings



DP wrote:

Peters 2000 includes a cladistic analysis that included all pertinent
prior cladistic analyses.

TW wrote:
Your analysis cannot have included the recent discovery of
well-preserved pterosaur ankles, which appear to align pterosaurs with
the Ornithodira.
I'm not saying that ankle characters should trump all other characters
that you claim link pterosaurs to protorosaurs; but the suite of
characters
present in the pterosaur ankle must be relevant to working out the
origins of this group.

Reference:


Kellner, A.W. (2004). The ankle structure of two pterodactyloid
pterosaurs from the Santana Formation (Lower Cretaceous), Brazil.
Bulletin AMNH
285: 25-35.

DP wrote:

No, you're right. My 2000 paper did not include Kellner's 2004 paper.
More importantly, Kellner's 2004 paper did not reference my 2000 paper,
which spent a fair amount of print on the tarsals of higher
protorosaurs. Looking at the tarsals, they are identical to
dinosauromorphs. Phylogenetically they are not. That's why one of the
"distal tarsals" of pterosaurs is really a centrale.

On a similar note, Unwin, Frey, Martill, Clarke and Riess (1996)
attempted to figure out what the heck a pteroid was in pterosaurs. They
discovered that it was indeed a bone, but they could never figure out
which one. Of course they ignored the possibility of pterosaurs being
protorosaurian in descent. Had they done so, they would have trumped my
2002 paper that identified the homology of the preaxial carpal and
pteroid as migrating centralia.

Tim, you really do need to see and think about both sides of an argument
before promoting one side over the other. To do so puts you in the realm
of science. With all due respect, to not do so puts you outside of
science, perhaps somewhere between politics, statistics and religion.


DP wrote:

         Peters 2002 is the account of the advent of the wing in
pterosaurs. Neither has been argued or trashed using cladistics or
         photographic evidence, both of which remain "the only games in
town."

TW wrote:
Without knowing what incipiently flighted pterosaurs actually looked
like, an "account of the advent of the wing in pterosaurs" is pure
speculation.
We have no _Archaeopteryx_ for pterosaurs - unless you are casting
_Longisquama_ or _Sharovipteryx_ in this role, which in either case is a
huge
stretch.

DP:
Ahhh, but we do have the Archaeopteryx for pterosaurs. And both of the
taxa you mention are the best candidates known to date. There has never
been a cladistic analysis that knocks either out of the ring. And if you
don't like these two, you can fall back to Cosesaurus and even
Langobardisaurus. Any of these four will beat anything offered up by the
archosaur guys.

But, that being said, I'd love to see a competing analysis. In four
years no one has even tried. Somehow it stopped being a "hot topic".  I
wonder why?

Read the papers and get back to me.

More later,
and Happy Holidays,

David Peters