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Re: Enantiornithines and Iberomesornis



Mickey Mortimer (Mickey_Mortimer111@msn.com) wrote:

<Well, you've presented no evidence that Ibermesornis is more basal than
"classic enants", and have not refuted Sereno's objections to Sanz's and
Chiappe's pre-2001 characters suggesting such. An "Enantiornithiformes"
has never been described from a cladistic analysis. Have you looked at the
literature? ;-)>

  I was being quite serious when I asked about bootstraps. It was a
concern of mine as I do not have the lit in this detail. Problematically
however, I do not actually need to prove an alternate theory of
relationship. What I saw and what I showed was that there is not a single
autapomorphy use to link *Iberomesornis* and to "prove" its referal apart
from alternate topologies. the features used to support its referal are
found "mosaically" throughout basal Aves up through basal carinatans. This
should immediately cast doubt on the support of a phylogeny, however ample
the characters at that particular node, to be anything like "more likely
than not" because it was the most parsimonious tree recovered. basal bird
systematics has repeatedly failed to find cohesive phylogenies over time
as a result of the lack of a truly robust database until Clarke and
Norell, and this matrix was briefer on included taxa than may be
desireable, and did not include *Iberomesornis*. Included taxa for enants
(aside from *Concornis*) have all been shown to be not only in the
Enantiornithiformes, but in the Avisauridae, which has been found in
various, if not cladistic, excercises, as the only stable as there are in
fact, among the Avisauridae and Enantiornithidae, few other cohesive
topologies. *Concornis* and *Sinornis* (or *Cathayornis* and *Sinornis*)
are more basal, and show up in polytomies with no real resolution, and no
friggin' wonder. Mosaic birds. What few features that tie them to
avisaurids and enantiornithids have been shown to be of questionable
validity by some workers, including Clarke, in criticism of Enantiornithes
as the current topologies appear to be using it as a form of junkyard for
basal birds. Many of these features appear to occur in basal birds all
over the place, and the vague similarities of the shoulder in
*Protopteryx* do nothing to aid its case as other features are missing
that are indicative of a relationship to enants; and this with several
complete skeletons. And this says what? That enant phylogeny is robust? Or
that the one apparent incontrivertible piece of evidence (hypapophyses as
reported) is sidelined by numerous features foudn through basal birds, and
show us _nothing_ but that *Iberomesornis*, as has been said for close to
6 years, may or may not be related to the basal radiation of enants.

  I need not prove anything. Just disprove. I have shown, or tried to,
that the character support is not only weak, but shaky at best and left to
one well-supported and apparently non-moasic character. This out of
complete postcranial skeletons. As for hypapophyses, these increase in
size in birds with longer necks, versus shorter, and attach long cervical
ventroflexors, and get bigger with size, also. I have been keeping my eye
out for a possible analysis of scaling effects of cervical/pectoral
vertebral features. This might be an interesting project for anyone with
time and grant money to burn.

  Cheers,

=====
Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)

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