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Re: wing ungual and digit V sightings
Release the hounds!
Well, if you ask for it... :->
First of all, sorry that I didn't trace anything today. I forgot. I'll try
to trace those photos and the above over the next 1 or 2 days. (I have
enough time for it -- I've almost finished entering the available
ornithischians into the database; most of the saurischians are still
http://www.pterosaurinfo.com/dimor_finger5.html: This _*IS*_ the Face On
Mars. It has the same resolution, the same blurriness, and even the color is
similar. If you can really cheat yourself _so hard_, I mean if you really
believe this kind of photo could ever contain _any_ information, you should
better look out you don't _accidentally_ shift around any mountains near you
(...OK, so there's not much danger in St. Louis). Well:
- The light comes from the left, it appears. This means that "mc V" is a
_depression_. A place where a chunk has broken out of the _matrix_ (there's
a _step_ in the matrix -- farther away from the bones it was prepared away
more deeply to expose eventual additional bones, closer to the bones it was
left there to prevent damage). The break surface continues a little into the
bone which looks as if something had gnawed it.
- The "claw" does not lie on the step, as the rest of the "finger" does. Not
only is the whole thing inside-out, it's also "preserved" in _two different
planes_! The line between the "claw" and the "penultimate phalanx" is the
edge of the step.
- As commonly, perhaps always, occurs with the photos you use, I can see
_several_ (in this case 3) possibilities for the precise shape of the claw.
Will take a long time to trace everything I want, I fear...
- All in all, it resembles less a digit + metapodial than a TRITYLODONTID
LOWER JAW. My tracing will look more convincing than yours! Look, the
"finger" forms a V-shape with a _second_ such string of raised features.
Clearly a tritylodontid lower jaw is a more parsimonious explanation than a
polydactyl pterodactyl! Since it is bas-relief instead of haut-relief, could
it be the bite mark of a tritylodontid? This would also neatly explain why
the region behind the tooth rows is missing. -- Er, yes, I am kidding, of
course. But of course I'll trace it anyway.
- Besides... when a digit gets reduced (what happened to tyrannosaurid arms
is not "reduction"), the first thing that shrinks and then disappears is the
ungual, because it is most expensive to build and maintain and most useless.
About half of this "finger" consists of the "claw". This would be strongly
selected against. Look at the average claw on the 2nd finger of a chicken.
_That_ is reduced.
http://www.pterosaurinfo.com/haopterus_finger5.html: This, too, is
bas-relief; as you can see _clearly_ in all photos, all shadows are on the
right. A break, still partly filled with matrix, leads into mc IV (a
_completely flat_ bone -- it was hollow, and it had tens of Ma worth of rock
lying atop it). You interpret its tip as a finger even though it's lower,
not higher, than its surroundings.
http://www.pterosaurinfo.com/noripterus_finger5.html: This is a continuous
ridge on mc IV. It has a pretty sharp edge. On its left there's a fossa for
muscle attachment or (considering the round black hole) the entry of an air
sac. Note that the ridge continues beyond the tip of the "claw" and loops
around the distal end of the fossa! The separation line between the "ungual"
and the "penultimate phalanx" is a break that goes through the entire mc IV.
There are no such lines between the "other phalanges", instead you
interpreted the bright spots as the joint ends. But such spots occur all
over the bone. You just wanted to see 3 phalanges and a metacarpal. (Note
the totally different proportions from "that" of *Dimorphodon*. What for?
The claw is still impressively large 100 Ma later.
http://www.pterosaurinfo.com/sordes_wing_ungual.html: Are you aware how
gihugrongous that "claw" would be? It would surpass the proportions of the
2nd manual claw of *Drepanosaurus* by far. The large curved dark triangle
above it is _the entire wing tip_, _with_ the wing membrane!!! No wonder
that the claw itself looks so much like an artifact of resolution. Its
totally straight left border is a row of dark pixels. Means, an artifact of
the _ridiculously_ low resolution. Most of it is the border of an irregular
dark patch, probably a dendrite (you have experience with low-res photos of
dendrites!). Its right border -- which only corresponds to the _lower half_
of the right border; when I try hard enough, I can see the tip of the claw,
but not the upper half of the right claw margin -- is probably the right
border of one branch of the dendrite.
http://www.pterosaurinfo.com/cycno_wing_ungual.html: This is obvious. The
"claw" is the area where they prepared around the wing tip. Ever wondered
why the finger claws of the Berlin *Archaeopteryx* have such white circles
(downward-pointing cones) around them? That's it. They continued into the
slab because the splitting surface didn't precisely follow the surface of
the fossil, so the preparator followed the claws downwards.
Left two pics: The left "claw" has the same explanation as above, with the
addition that the preparation caused parts of the upper layer to break away.
This produced the "tip" of the "claw impression". For the life of me I can't
see the right claw -- but I guess that's because the right wing finger is
(on my screen) _a cm farther right and above_! See that brown streak that
cuts off the top right corner? This is bone.
Lower right pic: Two wing finger tips surrounded by plenty of dendrites. In
http://www.pterosaurinfo.com/arthur_wing_ungual.html: Took me a minute of
trying hard to see the tracing in the photo. I'd bet reasonable amounts of
money that there's simply nothing there. A reddish circle identical to the
one on the "end of phalanx 4-4" (the "ligament depression") occurs in 2 to
10 other places on the left inset (depending how strict you are about the
color), including _on the bone_, the real bone, I mean. BTW... why is the
claw so deformed if it's a claw??? It must have been as soft as my sister's
nose when she was a baby (her nose and ears were quite slow to chondrify,
and are still softer than mine now that she's almost 13).
http://www.pterosaurinfo.com/mpum6009_wing_ungual.html: :-o Huh??? What's
this? A jpeg of a Hubble Deep Field compressed down to 0.3 %? I can't see a
claw in there. Or _anything_. I can't. BTW, if the thick, pointed bone in
the 2nd pic (from the top) is a phalanx 4-4, it has a nice and neatly
prepared pointed tip. It doesn't "fade into the matrix". (As if it ever
could -- it's not the same material, hey.)
Or wait -- actually I can see something in there: a bottle. The
shape of a good old-fashioned Coca Cola glass bottle. If I treat it as a
Rorschach test, that is. Gaze at the estimated 500 pixels for a minute or
two, and stimulus deprivation will kick in. The bottle is dark. Underlying
the claw that I still can't see. Wait! Now I can see it. Honestly. I'm not
one of those snickering types like HPs Tim Williams or Mike Taylor.
And precisely why shouldn't the wing claws be articulated? Why do
they have to have drifted to precisely that plane in which they can be seen?
Summary: Please don't get me wrong. I don't feel offended. Instead, I think
that you are trying _hard_ to insult _yourself_, your _own_ intelligence,
deeply. You're pulling both of your legs to flamingo proportions -- and you
don't even notice that it hurts. This is chutzpa -- again, to nobody but
yourself. I don't get it how anyone could treat one's own self in this way.
See you later when I'll upload the tracings.