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Re: =?unknown?b?TPw=?= and Li 2006, a review
David Peters wrote-
2. 34,000 most parsimonious trees were found and that's because the limit
the Max Tree was set at 34,000. Wow. That should be a huge red flag that
something is rotten in this tree and more work needs to be done.>
I'd agree here. It means the matrix doesn't have the ability to sort some
of the taxa. You can't always just add taxa to a matrix and expect them to
fall into one position.
Another problem with this paper is that the authors excluded three taxa
(Peteinosaurus, Nyctosaurus bonneri and "Ornithocheirus" compressirostris)
for no good reason. The authors simply defended this as being "because this
research focuses mainly of the relationships of Liaoning pterosaurs." But
why were these taxa chosen instead of other non-Liaoning pterosaurs? I bet
they caused more MPT's, but it would be nice for the authors to have stated
such instead of using the published excuse.
Jaime Headden wrote-
If I got to 34,000 max trees on my result, I'd realize that little would
result in fewer trees unless I started un-zeroing entries, which in the
authors' cases would mean pretending that some specimens were clearer or
complete than they really are.
Actually, PAUP often finds a more parsimonious set of trees, even after
34,000 is reached. Which would set the total number of MPT's back to 1
again. So Dave's right in that using a 34,000 max number of trees is a bad
A final problem is that the characters were ran unordered, when many are
clearly meant to be ordered. I wonder what running it with the characters
correctly ordered would do?
But in general, it was a good idea for a paper, and (like the other Korean
volume papers) was extremely up to date.