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Stratigraphic Symbols (was RE: Viva Neornithine Birds!)
> And basalmost loons still seem to make good candidates
> for C/P survival. Though they would probably be more
> like a neoavian version of _Gansus_.
>
Carboniferous-Permian survival? In birds?!?!
Okay, I know that you meant "Cretaceous-Paleogene". However, stratigraphy has
formal symbols just like chemistry or astronomy. And
in stratigraphy, C = Carboniferous, and P = Permian.
For the record, here are the standard symbols using the current ISC Periods:
Neogene = Ng
Paleogene = Pg
Cretaceous = K
Jurassic = J
Triassic = Tr (technically a capital T with small capital R attached to the
vertical part of the T. However, that isn't exactly a
standard ASCII symbol...)
Permian = P
Carboniferous = C
[For those interested in the subperiods of the Carboniferous,
Pennsylvannian is |P (a P with a vertical line to its left: again, a
non ASCII symbol) and Mississippian is M]
Devonian = D
Silurian = S
Orodovian = O or a capital Phi
Cambrian = C- (a C with a line through the middle, sometimes called "C bar").
While some editors and peer-reviewers (almost certainly of a more zoological
than geological bent) will let sloppiness over the use
of the symbols through, it doesn't make it correct. It is comparable to those
reviewers who let "Ornithomimosauridae" (or now, in
L&Z's paper, _Ornithomimosaurus_!!!) slip through.
Thomas R. Holtz, Jr.
Senior Lecturer, Vertebrate Paleontology
Department of Geology Director, Earth, Life & Time Program
University of Maryland College Park Scholars
Mailing Address:
Building 237, Room 1117
College Park, MD 20742
http://www.geol.umd.edu/~tholtz/
http://www.geol.umd.edu/~jmerck/eltsite
Phone: 301-405-4084 Email: tholtz@geol.umd.edu
Fax (Geol): 301-314-9661 Fax (CPS-ELT): 301-405-0796
> -----Original Message-----
> From: owner-DINOSAUR@usc.edu [mailto:owner-DINOSAUR@usc.edu]On Behalf Of
> evelyn sobielski
> Sent: Sunday, February 04, 2007 5:25 PM
> To: dinosaur@usc.edu
> Subject: Re: Viva Neornithine Birds!
>
>
>
> --- David Marjanovic <david.marjanovic@gmx.at>
> schrieb:
>
> > >>That is yet another question. Molecular dating
> > argues against the idea
> > >>that
> > >>*Polarornis* and *Neogaeornis* were loons --
> > >
> > > Does it? Ericson et al. (2004) seems to at first
> > glance, until you
> > > realize
> > > they only included Tertiary taxa to calibrate
> > their divergence dates. If
> > > you ignore the Cretaceous neornithine fossils, of
> > course the divergence
> > > dates will come out as too late to incorporate
> > them.
> >
> > No, no, I'm talking about van Tuinen & Hedges
> > (2004): when *Polarornis* and
> > *Neogaeornis* are assumed to be either crown gaviids
> > or stem gaviiforms and
> > as such used to calibrate molecular dating, the
> > results are patently absurd.
> >
> > http://dml.cmnh.org/2004Dec/msg00048.html (scroll
> > down to "Calibration with
> > Cretaceous loons").
>
> FWIW, the Waimanu paper *strongly* indicates that
> something like that should have existed then and
> there, and that it was not loons, but very likely
> close.
>
> Eike
>
>
>
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