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Non-Neoteny in the Palaeognath Palate



S.W.S. Gussekloo and R.G. Bout. 2002. Non-neotenous origin of the
palaeognathous (Aves) pterygoid?palate complex. _Canadian Journal of
Zoology -- Revue Canadienne de Zoologique_ 80 (9): 1491-1497.

Abstract:

  "Recent studies on the phylogeny of modern birds have indicated that the
Palaeognathae may not be the most basal group in modern birds, but are
derived within the group. This resulted in the revival of the theory that
the Palaeognathae have evolved through neoteny from a flying ancestor.
Neoteny was also suggested by other authors after finding palaeognath-like
characters in neognathous birds after experimentally induced neoteny
(neonatal thyroidectomy). In this study, we test whether the most
important palaeognathous character, the palaeognathous pterygoid?palate
complex (PPC), has indeed evolved through neoteny. We used a numerical
method to compare the morphology of the PPC of adult palaeognathous
species with the PPC of several stages of development of a neognathous
species. The results show that the morphology of the palaeognathous PPC
is, in general, very different from ontogenetic stages of the neognathous
species, indicating a non-neotenous origin of the palaeognathous PPC."

  I do not have access to the paper, but the abstract is hopefully clear
enough; it essentially supports what we already knew: palaeognaths
developed from flying less advanced ancestors. I mean, duh ...
lithornithids and tinamous, every body.... However, this study in very
intriguing to me, and as I do not get this journal anywhere nearby, anyone
out there have this able to send me a copy? I would love you forever....

  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.

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