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RE: How was that about Jaime and proof?

I'll just hit the highlights:

D. Marjanovic wrote:

<Instead, people have looked at the bone histology. [with regard to tiny pterosaurs] >

No bone histology studies exist regarding tiny pterosaurs, to my knowledge. If so, please provide refs.
And regardless of their histology, as embryos in eggs demonstrate, the morphology changes little from juvie to adult, so either can be used as evidence. David, you need to show one case, and one case only, of a juvenile that does not look like an adult of the same genus or larger clade - and doesn't resemble some other adult taxa that it is totally unrelated to. If you can, and if you do, then we can fight like rats in a cage about the details and evidence. Until then you have no evidence and your arguments are based on rhetoric and examples from other unrelated clades. Stick to pterosaurs.

< When anything gets adult, it stops having a juvenile or even subadult growth
rate and switches to a much slower rate or stops entirely. If you know one
exception to this, please do speak up. >

Not germane to the argument at hand but: 13-year-old-humans sometimes have babies. Otherwise, again, no bone studies on tiny pteros. And again, not germane if babies resemble adults and can fly shortly after hatching.

< It follows that your earlier suggestion that entirely juvenile- looking >

'juvenile-looking' by whose a-priori standards? No, they a short rostrum because they are related to short-rostrum rhamph-grade pteros.

< pterosaurs might be adults that had become sexually mature long before any
slowing of growth >

Again, the bone histology has not been studied in tiny pteros.

> If they are juvies, then why do they bunch together only at the five or
> six major morphological transitions?

<What (...if anything) is a major morphological transition?>

Oh, nice dodge, but let's not be coy... in prior work, the 'rhamph' - grade to the 'pterodac' -grade is what I'm talking about. And you know it.

> And why in gradually increasing or decreasing series?

<Because parsimony arranges everything in such series the best it can. It's
absolutely inevitable (once you get them not to cluster with their parents,
which is known to be easy).>

So, does this mean you no longer _believe_ or _have faith_ or _can trust_ parsimony?
'Absolutely inevitable?' That sounds like a scientific statement of fact. Can you provide an example or reference for this? You might have stepped over the line here. You can step back if you want to.
Above you state that I was able to 'get them not to cluster with their parents'. Okay, that implies that you know who the parents are. Please let me know so that I can reunite them with their kids.

> And for that matter: why not consider all anurognathids juveniles (big
> eyes, short tail, short rostra)? In fact, that's a great parallel!!
> Let's talk about that!

<I just said it: bone histology. I've told you several times. What's up? Am I on
your blacklist -- have I been there for most of the last year???>

To stay on subject: are there some anurognathids that are juvies? And some that are adults? If so which ones?
And once again, I know of no histological studies on anurognathids. If they exist, please provide refs. You seem to be the only source for such material. Don't let me down, David. With one fell swoop you can win this argument.

> I am telling you that it doesn't matter a whit if any pterosaur you > point to is a juvies or adult. It just doesn't matter.

< I am telling you it matters a whole lot. Putting juveniles and adults in the
same matrix without carefully coding the juveniles as "?" for every
ontogeny-affected character

David, can you list the ontogeny-affected characters in pterosaurs? From what I can tell of embryos in eggs. There are few to none. Again, you are my only source.

<is like putting the adults in twice, once
systematically exchanging apomorphies for plesiomorphies.>

And if so, then shouldn't they pair up? If not, what is attracting them to these dark corners of the cladogram where major morphological transformations are happening? And what of the tiny pterosaurs, the true babies, that are associated with parents, as in Pterodaustro? Why don't they move to these dark corners and join the others? Every specimen has to be looked at individually and coded 'as is'.

< (And that's not even mentioning the problem of size-related characters.) >

Can you make a short list of size-related characters in pterosaurs? I know of several size-independent characters, such as bone fusion in the proximal first wing phalanx of large Cretaceous pterosaurs. Not much else.

< Really. I'm dead serious about this. I've handled maybe 20 slabs with
*Lycoptera* on them by now -- there are lots of half-millimeter-high features
that you see or don't see depending on the lighting (which means, when the sun
shines, turn the slab by 180 degrees...).>

And I have handled Cosesaurus. The humerus disappears at certain angles. I'm aware of such things.

< Face it: you are kidding yourself, and because you like the results so much,
you don't notice that you are kidding yourself. >

No. The results speak for themselves. All you have to do is take my results and smash them using facts. So far you have been using rhetoric. If you want to be a scientist, and a hero to the DML, you'll take the challenge. I know it won't take long because you seem to have the facts at hand. What ever you do, don't shrink from exposing the charlatan, as Dr. Unwin did in his recent tome.

> And any data you might think to request has always been available.

< Only if you travel around the world and look at _the thing_ from several angles
under all manner of lighting. In 3D, you know. >

If you have a question about whether or not a certain claw or toe is visible in a fossil, ask and I will show you. And that's always been my policy. Your generalized rhetoric is not appropriate.

> If you simply label them juvies, as you do, you do so on faith
> that 'small' means 'young.'

< This is untrue, and by know you should really have noticed. >

This would help: 1. Which is the smallest adult pterosaur you know of?

> If you believe that juvies don't have similar proportions

<The other way around. The normal state of affairs -- the plesiomorphy -- for
vertebrates is that growth is allometric. That's the null hypothesis. The
extraordinary claim (such as sauropods having isometric limb growth -- not the
skull for example, mind you) is any deviation from this allometry, and this is
what requires extraordinary evidence (which has in the example been
forthcoming). >

I have ordinary evidence. Embryos in eggs. Tracings to the contrary have not been forthcoming.

< Oh, and, BTW, please utter some kind of comment on my tracings I did last
summer. You still haven't done that. Remember, if my tracings (the coke bottle
included! ;-) ) are anywhere near correct, they disprove yours of the same
photos. >

Sorry. I don't recall what you're talking about, including the Coke bottle (?). Please send again.
And, for the record, I appreciate the fact (?) (as you stated above) that tracings on photographs can be used as proof and disproof.

David Peters
St. Louis