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David Marjanovic wrote-
Oviraptorids don't have fused nasals,
Sure?
Yep. ZPAL MgD-I/95 (Osmolska, 1976), Citipati
sp. and Conchoraptor (Barsbold et al., 1990) all show unfused nasals.
Jaime says there is a Conchoraptor that does have them though... things are
never simple.
What about epipophyses on the cervicals, normally
present, absent in Calamosaurus, ornithomimosaurs and troodontids and
apparently not described for compsognathids? (Dirty little problem -- I don't
even know what an epipophysis is. :-] )
Knowing what a character is is important if you
want to code it. Epipophyses are processes on the dorsal surface of the
postzygopophyses. They are usually confined to cervicals, but some taxa
have them on anterior dorsals as well. Some taxa (eg. Ceratosaurus) have
very large epipophyses while others (eg. Gallimimus) have them reduced to
nothing in most vertebrae. It seems to be correlated with neck length and
head size. Ornithomimids have epipophyses on cervicals 2-4 and dorsals
1-3, and they are present in troodontids too from the axis to posterior
cervicals (Makovicky, 1995). The cervicals of Compsognathus are too broken
to determine the epipophyseal morphology (Ostrom, 1978). Calamosaurus does
appear to lack them in the preserved cervical, but who knows about the rest of
the vertebrae.
But these diagnosing characters are used to
find the clades, no? So I'd expect changes in the topology?
ACCTRAN and DELTRAN only affect those characters
with ambiguous distributions. Given a certain topology, it makes a
character diagnose a larger (ACCTRAN) or smaller (DELTRAN) clade, as long as
each is equally parsimonious. It's more complex than that, but no, it
doesn't change topology.
I've never found [...]. Microraptor and Rahonavis sometimes form a clade, with or without
Archaeopteryx.
Didn't you have that clade next to Troodontidae
when you left out the flight-related characters? Or was that somebody
else?
Oh, well maybe a no-flight-related analysis, but I
don't count those as they leave out [potentially useful characters a
priori.
Mickey Mortimer
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