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Re: EUROTAMANDUA & KIN
Darren Naish (firstname.lastname@example.org) wrote:
<What's this? The only bibymalagasian I know of is _Plesiorycteropus_.>
Bah, I meant *Plesiorycteropus*; me and my unholy non-memory
<While MacPhee described this taxon in great depth, and compared it with
all placental groups, he didn't ally it with any other group. I don't
think anyone has incorporated bibymalagasians into any phylogenetic study,
but at least a few workers have said that they think that they might be
allied to (or part of) the aardvarks after all.>
Curious. What was the justification for erection of a whole new "Order"
in the first place?
<The phylogenetic position of _Eurotamandua_ has been discussed at length
Szalay and Schrenk showed that _Eurotamandua_ lacks xenarthrous
articulations and thus is not even a xenarthran (and it only appears
superficially similar to _Eomanis waldi_ [which probably is a true
pangolin: _Eomanis krebsi_ is a juvenile of _Eurotamandua_]) and they also
excluded close affinities with pangolins (contra Shoshani et al. 1997) and
palaeanodonts (contra McKenna 1987). They conclude that it is
representative of a distinct lineage, the Afredentata, which has an
otherwise unknown fossil record. In their phylogram however they posit
lose relations with palaeanodonts and xenarthrans.>
Curious ... edentates and xenarthrans suck all into their bifurcation
burrows.... There can be no escape.
<Szalay's philosophical position on this is important: he applies
cladistics but argues for a 'Darwinian approach' in which the validity of
all characters are assessed (i.e., shown to be of phylogenetic 'value')
and parsimony tests are regarded as less than ideal because they
incorporate loads of junk characters. You can decided for yourself whether
any of this is more subjective than any other method. Szalay calls the
application of (computer-assisted) parsimony the 'consensus management
method'. No doubt his views are way more complex than indicated here, but
he can be thought of as a 'non-numerical cladist'.>
Sounds like a more philosophical version of myself. That is, where
theory is higher than the component equality of theory and math, given the
nature of the fossil record and phylogeny. I consider them tools to an
otherwise unknowable condition. Anyway...
Jaime A. Headden
Little steps are often the hardest to take. We are too used to making leaps
in the face of adversity, that a simple skip is so hard to do. We should all
learn to walk soft, walk small, see the world around us rather than zoom by it.
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