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RE: Erketu ellisoni online free access



Ken Carpenter wrote-

Nevertheless, the results pretend that we know something about the
question marks (as if they weren't there). The fact that the cladogram
matches a known cladogram is all the more reason to be skeptical since
it supports a preconceived idea. There is nothing wrong in science to
say "I don't know" than to pretend that we do.

I agree with Jaime here. This is what I was talking about in my Juravenator post regarding common misconceptions about cladistic analyses - taxa or characters with high amounts of unknown codings aren't necessarily detrimental. People should read Wiens' papers. They're online for free here-
http://life.bio.sunysb.edu/ee/wienslab/publicationpage.html
Some applicable ones to this issue are-
Wiens, J. J. 2006. Missing data and the design of phylogenetic analyses. Journal of Biomedical Informatics 39:34?42.
Wiens, J. J. 2005. Can incomplete taxa rescue phylogenetic analyses from long-branch attraction? Systematic Biology 54:731?742.


Paleontologists _constantly_ use phylogenetic frameworks to "pretend" they know something about unknown states. For instance, we infer Juravenator had a stomach, or that Erketu had a non-sigmoid femur. Paleontology's about using the limited data we have to find the hypothesis it supports best. If we're willing to say "I don't know - let's not bother trying" whenever a taxon is known from less than it probably takes to determine its phylogenetic relationships correctly, then we might as well throw all Mesozoic dinosaur phylogeny out the window. Even complete, living specimens aren't always enough to determine phylogeny 'correctly' at the level of detail our analyses currently involve - just look at extant lizards, mammals or birds. But I, for one, prefer having a working hypothesis when it comes to a taxon's relationships, even though I know it's not absolutely certain. I'm a scientist after all, and thus my reality is composed of uncertain, yet best-supported (for now), hypotheses. Those papers saying "I don't know" are merely an invitation for me to say "let me try".

Mickey Mortimer