Re: Phylogeny of South American Late Cretaceous mammals

[David Marjanovic <david.marjanovic@gmx.at>]

Or rather, their phylogenetic position!

I'd never have guessed that they're "symmetrodonts".

> a parsimony analysis of 137  morphological characters among 44 taxa.

*sigh* I don't doubt for a second that this analysis is bigger and 
better than any other on this topic before it. But. 137 is juuuust 
barely above 3 times 44. Experience strongly suggests that lots more 
parsimony-informative characters remain to be discovered, and that the 
number of characters is not even necessarily high enough to exclude 
problems from accidental sampling bias.

> Meridiolestida survived until  the early Paleocene (Peligrotherium)
> and early Miocene (Necrolestes) in South America, and their
> extinction is probably linked to the increasing competition with
> metatherian and eutherian tribosphenic mammals.

It's really hard to imagine such competition taking 45 million years or 
more. I still don't understand why people keep putting such vague 
speculations into their abstracts.

> The clade Meridiolestida plus  Spalacotheriidae is the sister taxon to
> Cladotheria and forms a new clade Alethinotheria.

True beasties? Like Alethinophidia?

(Therion is the diminutive of ther = "generic wild beast".)