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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 of
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 more
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 choice.


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.

Mickey Mortimer