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EUROTAMANDUA & KIN



Jaime wrote...

> As for *Pseudorycteropus* ("order" Bibymalagasia)

What's this? The only bibymalagasian I know of is 
_Plesiorycteropus_. 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.

> I have no knowledge of
> it's phylogenetics. Same for *Eurotamandua*, etc....

The phylogenetic position of _Eurotamandua_ has been 
discussed at length in...

Szalay, F. S. & Schrenk, F. 1998. The Middle Eocene 
_Eurotamandua_ and a Darwinian phylogenetic analysis of 
?edentates?. _Kaupia_ 7, 97-186.

Delsuc, F., Catzeflis, F. M., Stanhope, M. J. & Douzery, E. 
J. P. 2001. The evolution of armadillos, anteaters and sloths 
depicted by nuclear and mitochondrial phylogenies: 
implications for the status of the enigmatic fossil 
Eurotamandua. _Proceedings of the Royal Society of 
London B_ 268, 1605-1615.

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. 

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'.

-- 
Darren Naish
School of Earth & Environmental Sciences
University of Portsmouth UK, PO1 3QL

email: darren.naish@port.ac.uk
tel: 023 92846045