How was that about Jaime and proof?

[David Marjanovic <david.marjanovic@gmx.at>]

First I should mention that today I saw a poster on a, like, half-complete 
titanosaur from the LK (Allen Fm, Maastrichtian or a bit earlier) of South 
America. Good to see that not everything is a short caudal series!

So, here goes:

> > David Peters (davidrpeters@earthlink.net) wrote:
> >
> > > And yet, twenty years from now, after everyone accepts tiny pteros
> > > as adults, your children will have no problem understanding this
> > > form of evolution.>
>
> Jaime wrote:
>
> > There is no "this form of evolution" without proof, and one cannot
> > point to these juveniles and embryos and simply label them "adults"
> > without further proof. What the future will see is the argument from
> > nothing, that someone has asked people to suspend their disbelief and
> > just "accept" these are adults, without any primary data (none has
> > been forthcoming). This is a matter of faith and religion, and for
> > most reasonable people, is kept well separate from science which does
> > not tamper in faith.>
>
> Well hold on, partner! Just 'cause they're small and cute doesn't mean
> they're juvies.

Indeed not.

The thing is, nobody has ever claimed it were.

Instead, people have looked at the bone histology.

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.

> How did they get that way? Did someone say paedomorphosis?

Body size decrease by paedomorphosis includes a shortening of the juvenile 
phase of fast growth.

Just like how body size increase by peramorphosis includes an extension of that 
phase, as beautifully shown for *Deinosuchus* which kept juvenile growth rates 
till age 50 at least.

It follows that your earlier suggestion that entirely juvenile-looking 
pterosaurs might be adults that had become sexually mature long before any 
slowing of growth is _very_ special pleading. Doesn't mean it's unscientific -- 
find me an egg/baby inside any of these pterosaurs, and I'll have to reconsider 
my stance.

> 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?

> 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).

> 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???

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

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

> (And no B.S. about 'not being forthcoming' . My evidence was on the
> Internet in RGB for years.

Face. And. Pyramids. On. Mars.

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...).

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

> 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 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.

> 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).

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.
-- 


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