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Re: Sharovipteryx an ornithodiran??



Go get the opposing evidence: My evidence is on the website: pterosaurinfo.com.
and it shows up, or will show up in Prehistoric Times. [...]


So much bs Jaime. Quit pontificating and start laying out the prosecution.

Then why have you never commented http://dml.cmnh.org/2005Aug/msg00123.html?

Similarly, arguing about "pterosauromorphs" being crocs from an abstract is
not the same as examining the material, or at least reading the dissertation
itself, which I highly recommend.

I can take apart the evidence written in the abstract point by point and I have
done so in correpsondence with the author.

Why not just W4tP?

It's been five years since that Macrocnemus > pterosaurs theory hit the presses.
No one has dented it yet. No one has called it into question.

Compiling a phylogenetic analysis the size of yours takes a lot of time. Someone will do it sooner or later. Don't get impatient. :-)


If there is anything wrong with the
macrocnemus hypothesis, someone would have pointed out a flaw by now.

I happen to know of a paper that was accepted for publication a few months ago and will be actually published _NEXT_ January. I've also heard of similar horror stories involving other journals than this particular one. The speed of science is limited...


Or if PAUP had found a better match, someone would have alerted us by now.

_If_ anyone had done an amniote phylogeny.

More bs. The skull is complete.

http://www.pterosaurinfo.com/sharovipteryx_skull.html does not provide any evidence for this claim (or the presence of the pineal foramen, for example). The resolution to tell simply isn't there. BTW, the right "insect" looks more like an ostracod, while the left one is delimited by breaks. This is very easy to see by comparing the tracing with the photo -- try finding the insect on the photo, and you'll find a couple of nice breaks.


The pec girdles are there.

Yes, but a) split RIGHT THROUGH THE BONES (apparently there are two slabs -- oh yes, there are two, you say it on the main *Sharovipteryx* page) and b) not prepared.
The right preacetabular process you identify is a piece of rock on top of where the process should be, assuming it really is that long. I can't see the right postacetabular and the left preacetabular processes. I conclude that they simply aren't there, except maybe if deeper inside the slab or the counterslab. BTW, you ignored the wall of the right acetabulum. It is there, and it is visibly bone rather than matrix, yet you didn't trace it.


The problem may be in
the amount of skin still present obscuring certain features. And, of course the
big cracks in the matrix.

And of course the splitting of the slab has split the fossil. The area where the forelimbs should be in http://www.pterosaurinfo.com/sharovipteryx_insitu.html isn't "filled with some sort of filler". As you can clearly see it is _below_ the fossil. In this area the fossil has entirely gone with the slab, leaving empty matrix on the counterslab. The "filler" is the next layer of sediment. This is really obvious. Except maybe if bumping up the contrast takes all the 3D away.


The arms are incomplete,

More bs. And I'm not the only one who has seen the arms now. Two others I know of
in separate hemispheres.

http://www.pterosaurinfo.com/sharovwinglets.html
Face on Mars. You just traced anything that seemed to continue any bone shape you found, no matter if it's black or white.
Just about the only feature that I can see is the tip of the "right" 4th finger. Please note that you seem to have put the boundary between the ungual and the penultimate phalanx in a place where the rock is almost completely smooth (AS FAR AS I CAN TELL FROM THIS BAD PICTURE!). You ignored several places that are darker than this supposed boundary between phalanges. All of them would completely ruin the shape of the "phalanges".
I can, however, see the legs and hindwings and partial vertebral column (not traced). The "right 3rd claw" could easily be part of a vertebra.


Consequently I reject the "bs" hypothesis.

and I do not agree with Dave's interpretation of long
arms, given the remains are also partially disarticulated and thus,
untrustworthy regarding consistency of form.

More bs. The remains are completely articulated. Just crushed.

No trace of them is visible. If they are there at all, they are still deep (!) in the matrix.


But basing a nesting on a few key features is dangerous.

This is obvious.

Take 150 to 225 characters and then feel safe about a nesting.

If you are sufficiently sure that there aren't any characters in there that are correlated to each other or ontogeny, if you are sure that you have ordered them correctly, _and_ if you are sure that there is phylogenetic signal in them; _and_ if you don't have so many taxa that you'd need such a number of characters just to POTENTIALLY produce a fully resolved tree; _then_ yes. (The presence of phylogenetic signal can be tested by three or so clicks in Mesquite once you have your matrix and a tree in there. http://mesquiteproject.org)