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Re: Phylogeny of South American Late Cretaceous mammals
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".)