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Re: Reduced Consensus (Was: Afrotheria revisited)
Mike Taylor wrote-
>> Would it be possible to get a DIFFERENT well-resolved tree by
>> excluding one of the other taxa (this is something that time and
>> computer power could check!)?
> Yes it would.
Just to be clear -- you're talking here about _a priori_ exclusion,
Yup. Just like the authors excluded Arsinoitherium a priori.
You're asking for a whole phylogeny of placentals in that case. For
example, if you include carnivoramorphs, then you have to include
'creodonts'... and so on.
Of course. Tambuci et al. want their analysis to meaningfully support
Afrotheria, but how can they expect that when they have a whopping 2
boreoeutherians (3 assuming mesonychids are...)? And they're not even basal
members of the clade. Indeed, they're members of boreoeutherian clades that
are most convergent with paenungulates.
Is this partly the consequence of low taxon sampling? Would adding more
taxa for certain clades help 'firm up' the bootstrap support for some of
the clades? In the analysis above, some very speciose clades (like
Proboscidea, Perissodactyla, or Artiodactyla) are each represented by only
one (fairly basal) taxon.
Very much so. Imagine a theropod analysis of tyrannosauroids that threw in
an abelisaurid and a carcharodontosaurid without bothering with basal
ceratosaurs or carnosaurs. Then add in Megalosaurus as the outgroup because
it's a fairly plesiomorphic "Carnosauria" incertae sedis. And analyze the
mix with 10 characters, but only from the maxilla and femur. That
approaches the futility of Tambuci et al.'s matrix. It's great somebody's
finally trying to figure out where everything goes, but it needs a TON of
I have a hard time imagining how mammalogists don't go insane with so many
major groups of mammals that have utterly unknown relationships. That never
happens with dinosaurs. At worst we have grades of taxa with uncertain
branching order ('hypsilophodonts', 'compsognathids/coelurids',
'prosauropods'), unresolved trichtomies (Troodontidae vs. Dromaeosauridae
vs. birds) or multiple well-supported conflicting topologies
(Alvarezsauridae). But mammalogists have asioryctitheres, leptictids,
anagaloids, zhelestids, dinoceratans, xenungulates, astrapotheres,
litopterns, notungulates, arctostylopids, etc. etc.. Madness.