[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

RE: Longisquama's "feather-like" appendages in new study



Well, we now have four papers on Longisquama's parafeathers published in the 
last twelve years.  Surely it's about time somebody redescribe its osteology, 
since it is such a controversial taxon.

Mickey Mortimer

----------------------------------------
> Date: Mon, 5 Mar 2012 10:02:09 -0800
> From: bcreisler@gmail.com
> To: dinosaur@usc.edu
> Subject: Longisquama's "feather-like" appendages in new study
>
> From: Ben Creisler
> bcreisler@gmail.com
>
>
> A new online paper:
>
> Michael Buchwitz and Sebastian Voigt (2012)
> The dorsal appendages of the Triassic reptile Longisquama insignis:
> reconsideration of a controversial integument type.
> Paläontologische Zeitschrift (advance online publication)
> DOI: 10.1007/s12542-012-0135-3
> http://www.springerlink.com/content/c25022htl3663053/
>
>
> Elongated skin projections of the reptile Longisquama insignis from
> the Triassic of Kyrgyzstan are preserved as imprints on the only
> skeletal specimen and on seven additional pairs of fossil slabs and
> counter-slabs from the same locality and horizon. The integumentary
> structures became a matter of debate when they were assessed as
> “non-avian feathers” homologous to avian feathers. Conflicting
> interpretations of their morphology and relationship to other
> appendage types arose from the ambiguity of the fossil skin
> impressions. On the basis of comparative description of the individual
> morphology of all yet known Longisquama specimens we address aspects
> of taphonomy, development, and function and define to what extent
> Longisquama’s appendages share characteristics of avian vaned
> feathers. We explain the existing feather similarity by their
> development from a filamentous primordium and a complex sequence of
> individual processes, some of which are reminiscent of processes
> observed in feather development. Such an interpretation is in
> agreement with a set of homologous mechanisms of appendage
> morphogenesis in an archosauromorph clade including Longisquama and
> feather-bearing archosaurs but does not necessarily require that the
> appendages of Longisquama themselves are feathers or high-level
> feather homologues.