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Tyrannosaurid teeth carinae

From: Ben Creisler

A new paper that has not been mentioned on the DML yet:

Miriam Reichel (2012)
The variation of angles between anterior and posterior carinae of
tyrannosaurid teeth.
Canadian Journal of Earth Sciences (advance online publication)
doi: 10.1139/e11-068

Tyrannosaurid tooth measurements have been shown to be a powerful tool
for systematic analyses, as well as for studies on function and
evolution of theropod dentition. In this analysis, a variable not
previously addressed in depth is added to the tyrannosaurid data set.
The angle between the anterior and posterior carinae can be difficult
to measure consistently and a method is hereby proposed through the
use of a digitizer. Five tyrannosaurid genera were analyzed:
Tyrannosaurus, Tarbosaurus, Albertosaurus, Daspletosaurus, and
Gorgosaurus. Only in situ data were used, and therefore some of the
taxa had a limited amount of information available for this analysis.
The measurements were analyzed through multivariate analyses using
Paleontological Statistics (PAST), version 2.06. The analyses included
principal component analyses (PCAs), discriminant analyses (DAs), and
canonical variates analyses (CVAs). The results of these analyses
revealed that the angle between carinae contributes significantly to
the variation in the tyrannosaurid tooth data set. Additionally, this
variable showed a strong correlation to tooth function (and,
consequently, to tooth families), rather than tooth size. The
variation observed between taxa at this stage seems insufficient for
systematic purposes, however additional in situ data would help
improve the effectiveness of this tool.