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Re: Lü and Li 2006, a review
On Jun 6, 2006, at 4:14 PM, Jaime A. Headden wrote:
David Peters (firstname.lastname@example.org) wrote:
<1. Well, the choice of the outgroup taxa dooms the base of this
study from the
start. Pterosaurs are lizards, not archosaurs as shown by a
2 to 14 times larger and more inclusive than any prior attempt at
I doubt whether the outgroup would have influenced the deeper
pterosaurs much at all, though it might shift the base around a
So, Jaime, why make a red herring negatory comment if you are in
tacit agreement with my statement? It makes you look bad, my friend.
Argumentative, just for the sake of being so.
<2. 34,000 most parsimonious trees were found and that's because
the limit of
the Max Tree was set at 34,000. Wow. That should be a huge red flag
something is rotten in this tree and more work needs to be done.>
If I got to 34,000 max trees on my result, I'd realize that
result in fewer trees unless I started un-zeroing entries, which in
authors' cases would mean pretending that some specimens were
clearer or more
complete than they really are.
You're guessing and you're guessing wrongly, speaking as one who has
done the work. I would be more convinced that these workers had done
their work if I had seen labeled tracings and reconstructions.
Roadkills are devilishly mysterious, until the CSI guys dissect the
scene. Adding characters and taxa would solve their massive MPT
problem. The data is available. They just took the easy path by
adopting Kellner's work.
<3. As usual, the highly derived pterosaur, Rhamphorhynchus, is
shown to be the
sister group to the classic 'Pterodactyloidea' when anyone with an
would be hard-pressed to find a synopomorphy or two uniting the
two. In an
unpublished cladistic analysis of greater breadth, Rhamporhynchus
is a highly
derived dead end leaving no progeny and the pterodactyloid grade
times by convergence from dorygnathids twice and via basal
It's a "highly derived dead end" in EVERY cladistic analysis to
which comes from the nature of it's peculiar cranial anatomy.
Not so here, my friend. Show me one study that has Rhamphorhynchus as
a dead end without sister progeny. It's always the last bus before
Less confusing, I
am sure, is the more plesiomorphic postcrania.
"I am sure" is a well-known weasel phrase for "I have room for for
doubt but don't want to express it." Better to leave out this phrase.
And the postcrania is not as plesiomorphic as you might assume. In my
study, there isn't just one Rhamphorhynchus, but a whole bush leading
from Campylognathoides alone, with lots of variation in every part of
Then again, pterosaurs like
*Dorygnathus* and *Sordes* has very similar jaws and skull structure,
And for good reason. Sordes is a short-tooted type of Dorygnathus, as
are all subsequent pteros. Not the other way around, which is how Lü
and Li portray them.
doubt Rhamphorhynchidae is very incoherent in the current pterosaur
??? You've phrased that incoherently.
As for the polyphyletic treatment of some clades, one must wait
for testable, available results to consider claims of such oddity,
such would exist.
<5. No tiny pterosaurs (typically known from numbers rather than
included, which also screws up the results royally. Tracings of
eggs show that their proportions do not differ greatly from their
any so-called assignments of short-rostrum 'juveniles' to long-
are false and misleading.>
These specimens are not included for what, it seems to me, is a
reason: they are considered juveniles by just about every pterosaur
That's tradition and paradigm. Test them. No one has yet. Don't be
afraid to. It's not that much work.
Not because they assume it to be true, but because a good deal of work
has gone into considering them and relegating them as juveniles,
taxonomic assignment can be shaky (which it may be).
Not so, small size was assumed to represent juvenile status and long-
winded explanations were devised to promote the idea despite changes
in bone, tooth and proportion that could just as easily, and it turns
out, more readily, to have been phylogenetic. If I were wrong, I
should be the one with 34,000 MPTs. Right? Right? No I have one tree,
and all the sister taxa blend, like Mr. Darwin said they would.
Only one person it seems
considers them adults, and for reasons that it would appear NO ONE
him on (that no one referring to pterosaur workers or anyone who's
Many discoveries, from continental drift to a heliocentric solar
system, were made by mad men working alone with various sorts
pointing fingers and calling names. And you, Jaime, are one of the
sticks in the mud, as you'll discover someday.
Finding proof these aren't juveniles would be considerable, but
so far, no data demonstrating this has been published.
Not for lack of trying. The strategy now is to publish and finished
revision of the Amniota, then work to the branches.
The paper Dave published
on a few juveniles found inside eggshells are just that, juveniles
At the time, you'll remember, the specimen inside the eggshell was
the size of a typical adult anurognathid. It's still an anurognathid.
Only a juvenile of a much larger one, only one of which is known in
the adult form. This is called making an honest mistake, which I was
glad to announce at the discovery of the second and third pterosaur
eggs. Altogether this is called progress. Or science.
Additionally, "ephemera" (that which disappears with a second look)
do not prove the adulthood of an adjacant specimen.
I submit to you, Jaime, that the bits and pieces of the entire baby
pterosaur are present and visible inside of each egg. Actually, the
bones are 'packaged' rather nicely in their original containers. I
have traced them. All the bones connect as they should. The work has
been widely available for years.
So, there is good reason
not to include these specimens in a matrix.
Yes, put your head in the sand and avoid testing when it would be so
easy to do so. And so rewarding. I encourage you to put any tiny
ptero in a matrix and see where it falls. A dozen would reveal more
If anything, this inclusion is what
I suspect is resulting in the rather topsy-turvy result of
and non pterodactyloid pterosaurs in Dave's own analyses (testing
to this idea
would require REMOVING THEM to see the results).
Removing the tiny pteros does indeed bounce the cladogram back to a
ladder -- but then you have to deal with sister taxa that do not
blend as Darwin said they should.
There is something deliciously wonderful about lifting the veil of
ignorance and seeing unexpected truth after years of work. There is
also something devilishly charming about certain folk who play their
part so well and create unnecessary drama about such trivia.
Back to you.
Jaime A. Headden
"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)
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