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Re: Hanson 2006, Mortimer, Baeker response
> > Unresolved points, by definition, raise the number of trees above "1". So,
> > you speculate in error. The number of unresolved points is zero.
> Now it starts to get funny: You say that it is not surprising that
> your ptero cladogram is perfectly resolved and that the situation in
> dinosaurs is similar. I argue that it is not and suddenly we are back
> to "My cladogram is right because it produces only 1 MPT"? *You* were
> the one claiming that dinosaur cladograms are well-resolved, not me.
Martin, I limit my argument to my cladogram of pterosaurs. I say nothing about
anyone else's cladogram of dinos. You said: "if we look at a cladogram
as many species as your probably does, the number of unresolved points is
guess you meant in _any_ cladogram with many species there are many unresolved
points. I meant, despite the large number of species in _my_ cladogram the
of unresolved points is zero.
> To be honest, I am not much in pterosaurs and I couldn't care less how
> their tree will be resolved. I do not argue against certain cladogram,
> but against what seems to me bad science, and that's were I get
I appreciate your candor. If I were to suspect bad science in a cladogram, I
as I was able to do with Hanson's cladogram dissect it piece by piece. If I
not dissect it at face value, I would have asked for the data in order to try to
understand the patterns and perhaps come to a new appreciation of a new way of
looking at things. I note that you have not attempted to dissect my cladogram
by piece. I'm not sure that you have even seen my cladogram. And if not, you are
railing against what?
> No, but IMHO the evidence for 2+2=4 is slightly better than that for
> all those tiny pteros.
And yet, twenty years from now, after everyone accepts tiny pteros as adults,
children will have no problem understanding this form of evolution. After all it
falls into a well known pattern: tiny cynodonts became mammals. Tiny dinosaurs
became birds. Tiny amphibians became reptiles. Tiny archosaurs became
happens all the time.
> > > Not that it is impossible, but too many
> > > times in the past those all-explaining theories were just wrong.
> > Too many times? Can you name two times?
> I can name as many as you like: Astrology, mesmerism, shamanism,
> vodoo, UFOs, ..
> All these pseudosciences claim to explain it all (And most of them
> claim to be scienctifically provable). So if you find a theory that
> does likewise, make sure that you don't enter pseudoscience.
Ahh, I was limiting my thinking to the eu-sciences, like plate-tectonics,
universe, evolution. Interesting.
> > > Ending with a 1-MPT cladogram does *not* prove you right, no matter
> > > how nice it looks. (It does not prove you wrong, either.)
> > Thank you for that. Again, proof is impossible in a cladogram. It's not the
> > goal.
> But, surprisingly, you argue all of the time that your cladogram is
> better than others because it has a better resolution (1 MPT). (See
> statement above: "My cladogram solves more problems than any other" -
> may be true, but does not make it right.) I'll just repeat it one
> final time and then I'll rest my case: The *outcome* of a
> cladogram cannot prove it valid or invalid, it is the *input* that has
> to be scrutinized.
I'll say once again, when you repeat the word "prove" it sounds like you're not
listening. At all costs, avoid the word "prove." And taxon exclusion leads to
problems in cladistic analysis, as I can "demonstrate" over and over in many
clades, from bat ancestry to turtle ancestry. You're trying to exclude taxa.
> As my philosophy teacher told us (one of the few useful things I got
> from there): From a wrong premise, you can conclude anything, even a
And as history will tell you, attitudes and prejudices color thinking. Consider
widely accepted stoning, slavery and tail dragging were. You've simply been
indoctrinated. You need to open your mind just a wee bit.
> No, no, and no again. To prove it a juvenile, look at the bone structure.
> > > But to find out whether it is a juvenile or not, you cannot look at
> > > cladograms - look at the proposed juvenile's bones and check whether
> > > they are fully ossified, remodeled, whether sutures have closed etc.
> > I have and they're adult-like.
> Wow - I did not know that anyone so far was able to section these
> bones. Are they fibrolamellar? How large is the osteon density?
So there we are: you just told me that the bone structure has not been
So, why do you say No. 9 is a juvenile based on bone structure?
> > But with neotony, and considering their
> > absolute size, is it impossible for tiny pteros to have shorter lifespans
> > and
> > to be having sex and laying eggs prior to complete ossificiation? I'll not
> > bring up humans here, because we all know that story.
> Impossible is nothing (Adidas), but highly improbable. ;-)
> So, they are *not* fully ossified in direct contradiction to your
> statement in the previous paragraph?
I'm saying fully ossified or not, tiny pteros can have sex with each other and
> And yes, it is *very* improbable that they are nor fully
> ossified. Wing bones in animals are selected for stiffness, mainly
> (and toughness, next). Stiffness is governed by mineral content. An
> unossified flyer would have lots of trouble with torsion and bending
> in the wings - can't see how selection would not manage to ossify
> earlier in individual history in this case.
And yet, some baby birds fly immediately upon hatching. And Dr. Unwin suggests
same for pterosaurs. So your argument has been falsified.
> > > But it was *your* argument stating that these tiny pteros would fit
> > > because there are tiny birds nowadays, so this is something beyond a
> > > cladogram. And this argument I reject - just because nowadays (with
> > > mammals and birds) niche-partitioning is done species-wise doesn't
> > > mean it was so always.
> > In many batches of offspring, some are larger and some are smaller than
> > others. Natural selection works its wonders, sometimes in a series of size
> > squeezes or size balloonings, which is exactly what I see in the cladogram.
> > A
> > series of gradual increases and decreases.
> So again you use your cladogram to prove your cladogram...
And again, you use the word "prove". You really must not let that word reenter
conversation when talking about hypothetical relationships. Martin, in
we look for patterns. It is the patterns that provide insight. We can argue and
should argue about characters and taxa, but one of the rules of this game is
we never say the word "prove."
My best to you and your studies.
I think we've beaten this horse to death.
> Priv.-Doz. Dr. Martin BÃ?ker
> Institut fÃ*r Werkstoffe
> Langer Kamp 8
> 38106 Braunschweig
> Tel.: 00-49-531-391-3073
> Fax 00-49-531-391-3058
> e-mail <firstname.lastname@example.org>