RE: a closer look at Hanson 2006, Mortimer response

[Martin Baeker <martin.baeker@tu-bs.de>]

> A metaphor for what you are saying is: "Don't cross the street. You might get
> hit by a car." Many referees do the same thing to everyone's frustration.
> Without saying so specifically they throw out such general red herrings and
> orange cones by saying essentially: "It's possible that what you are doing is
> in some unspecified way dangerous."

No, I think what Mickey said is "The number of MPTs you get in the end
is not a measure of the quality of the analysis". If knowledge of the
fossil record is incomplete, you would expect a large number of MPTs.

Your argument looks like a classical logical fallacy:

"The correct, perfect analysis should have only one MPT. 
My analysis produces only one MPT.
Therefore, my analysis is correct."

> My single MPT is chronologically accurate, avoids untenable reversals, puts
> derived characters at the tips of branches and bottom line: you can  line up
> the taxa in a visual spectral blend like rhipidistians emerging from the
> swamps and morphing into humans lurching over computers.

Shouldn't that make you suspicious? It would be the first cladogram I
ever heard of that contains nothing like ghost lineages, things
disordered wrt time, reversals (shouldn't we *expect* reversals?
Evolution is not directed, after all.) etc.  It would mean that our
knowledge of pterosaurs is complete and perfect.


> It passes any test
> you can put upon it.

This is really a dangerous statement to make. Did you think of and try
all possible tests?  As Feynman said: "The easiest person to fool is
yourself."


>Anyone who claims No. 9 is a baby Pterodactylus and not a minute
>variation of Scaphognathus will have to do so scientifically, perhaps with a 
>cladogram.

How could a cladogram prove such a thing? It can only sort beasts
based on characters, but it cannot find out the meaning of those
characters. To see whether something is adult or not, look at bone
sutures, or, even better, bone microstructure (see the Europasaurus
paper for an example of this). 

> The smallest known pterosaurs, I remind you, are no smaller, nor in any
> parallel universe different than the smallest known adult birds and bats. They
> are volant from the time they leave the egg.

True, but we are not talking mammals or birds here. If you look at the
growth rate of, say, a t rex, you can (with some reasonable assumption
on mortality) easily calculate that the *biomass* of small rexes (less
than 1 ton) was probably larger than that of adult rexes. Meaning,
juveniles filled a different ecological niche, and probably filled it
very well. If the same held for pterosaurs, then there were lots of
tiny pterosaurs filling the small-size ecological niche - just not of
a different species.

> I also remind you that the smallest adult lizards can fit comfortably on a
> dime.

For pterosaur adults, this would mean they would eitehr have to give
up homoiothermy or they would need an incredible amount of food (like
an etruscean screw, for instance). Not impossible, but it's a stretch, I think.

Martin.

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