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*Henosferus* and mammal...imorph phylogeny
-------- Original-Nachricht --------
Datum: Tue, 05 Jun 2007 09:37:01 -0600 (MDT)
Von: "Richard W. Travsky" <email@example.com>
Betreff: Introducing Asfaltomylos's sister
Thanks for the link, I just finished reading the paper. The authors try both
ordering some characters and keeping all unordered. The ordered analysis finds
three MPTs; their strict consensus "collapse[s] the eutherians into an
unresolved tetrachotomy and also collapse[s] *Kielantherium* and *Aegialodon*
in a position basal to Theria. The unordered analysis resulted in a single most
parsimonious tree [...] that resolved the eutherian clade, the relationships of
*Kielantherium* and *Aegialodon* (grouping them in a monophyletic sister-group
to therians), and, most surprisingly, moved *Haramiyavia* from a sister-group
relationship to tritylodontids [...] to a position basal to Multituberculata".
Sometimes, then, having more MPTs is better.
That said, including more eutherians would probably have helped -- there are
only four in the analysis: *Montanalestes* (AFAIK an isolated tooth),
*Asioryctes*, *Erinaceus* (the extant hedgehog), and *Prokennalestes*.
The content of the mammalian crown-group is much smaller in this analysis than
`--+--*Haldanodon* (*Castorocauda* is not in the matrix)
`--+--*Priacodon* + *Trioracodon*
`--+--*Gobiconodon* + *Amphilestes*
Within the crown-group, *Deltatheridium* is outside of (*Pappotherium* +
Theria). That may be because *Eomaia* and *Sinodelphys* are missing. If *D.*
moves, the trichotomy the (*D.* + (*P.* + Theria)) clade forms with
*Aegialodon* and *Kielantherium* might be resolved.
*Fruitafossor* is missing, too...
Then the authors argue for a reinterpretation of the tooth cusp homologies of
Australosphenida, modify the matrix accordingly, and run it again, with the
same characters ordered as before. The multituberculates jump into the
crown-group -- "inside Australosphenida as the sister-group of Monotremata, a
result also obtained during the standard runs under certain conditions." :-o
OK, that's it. I retract all claims of certainty about basal mammal phylogeny.
Running the modified matrix with all characters unordered produces 33 MPTs and
a poorly resolved majority-rule consensus. "This area of the tree [around the
base of the crown-group and within Australosphenida] is obviously very labile
and susceptible to drastic topological collapses, probably due to the lack of
cranial, postcranial, and upper dental information for most of the
While I am at it, the name *Henosferus molus* has a few problems.
Firstly, a "holotype" is designated for the genus instead of a "type species".
The intent is obvious and unambiguous, so I don't think anyone will bother, but
the letter of the Code is violated. -- This may be connected to the fact that
the paper is chock full of typos (mostly trivial, but including "*Henosfenos*").
Secondly, henos is explained as Greek "old", and ferus as Latin "animal" -- but
it means "wild", not "animal"! We have thus an uneasy concatenation of two
Most importantly, molus is explained as "From the Latin _mola_, meaning
millstone [...]". But there are no transgender millstones. _mola_ is a noun in
apposition, not an adjective, so the correct name is *Henosferus mola* --
unless a literalist insists that no type species has been designated, that is.
Psssst! Schon vom neuen GMX MultiMessenger gehört?
Der kanns mit allen: http://www.gmx.net/de/go/multimessenger