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RE: a closer look at Hanson 2006, Mortimer response
<<David Peters wrote-
Above I have listed many 'bumps' in your 'blend'. If your
results produce a hundredth of 34,000+, then your results produced
340 trees. Right? That's still too many, and more than one, which is
the number you are competing against.
A comment regarding an impression I get from you, David- the number
of most parsimonious trees found by PAUP is not indicative of the
accuracy of the results. A large number of most parsimonious trees
merely means the analysis lacks the characters needed to place
several taxa unambiguously. It's possible to make a single MPT that's
grossly inaccurate due to not including conflicting characters, not
ordering characters, ignoring ontogeny, etc.
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
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. It passes any test you can put upon it. Add
as many characters as you wish. Add as many taxa as you wish. Order
what you want. But remove the little ones and you're sunk. So you
must ignore ontogeny in this case. And for good reason.
Also, you should know that a cladogram of this size is extremely
robust. You would have to show that dozens to hundreds of characters
were coded incorrectly -- and not only that, but the the corrections
ALL would tend to push the tree into a different direction. That's
because if an error is found, it might (50/50) actually strengthen
Now from you, I need an example of how ignoring ontogeny destroys
trees. AND I need you to show me one example of a baby pterosaur that
does not look like its parent (you need to come up with two
specimens) -- and this baby pterosaur cannot look more like some
other pterosaur. That's the challenge. 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.
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.
I also remind you that the smallest adult lizards can fit comfortably
on a dime.