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Re: Afrotheria revisited
I've looked at the Tabuce et al. article and there is something
methodologically eyecatching about it (attention Micky Mortimer).
(I'm afraid the methodology is the only connection this letter has to
There are two cladograms described as the strict consensus trees
on the basis of 52 character traits. One is said to be the consensus
of 105 equally parsimonious trees, of length 225, and is pretty much
phylogenetic grass. On the same page there is another tree, the
strict consensus of 4 equally parsimonious trees of length 214: a
remarkable improvement, since it is almost totally resolved (3
trichotomies, as opposed to the "16-otomy" in the first). No comment
is made about the difference between the two, and it took a minute of
looking-- and counting the taxa covered in the two analyses-- to
figure out what the difference was: the 52 traits gave grass for 23
taxa, but almost perfect resolution for 22.
The procedure may well be legitimate (the taxon dropped is
Arsinotherium, and I can imagine it being autapomorphic enough to
confuse an analysis of the others), but it FEELS like throwing out
inconvenient data and I'd have preferred some discussion.
DISCLAIMER: This isn't really my area of expertise, I'm an
amateur, and if people who really know about how to do phylogenetic
analyses tell me it's o.k. I'll just have to believe them.
University of Melbourne