Dear MARMAM subscribers,
We are pleased to announce
the publication of the following paper in the current issue of Zoomorphology:
Dental anomalies in pinnipeds (Carnivora: Otariidae and Phocidae):
occurrence and evolutionary implications
César Drehmer,
Daniela Sanfelice and Carolina Loch
Zoomorphology, Volume 134, Issue 2, Pages 325-338
Abstract
Dental anomalies comprise
variations in number, shape, size, position and occlusion of teeth, mainly
caused by genetic mechanisms. This study aimed to investigate the nature and prevalence
of dental anomalies in a large sample of pinnipeds (Otariidae and Phocidae) and
to discuss potential evolutionary and ecological implications. Thirty-four
species in twenty genera were sampled. The dentition of the specimens examined
was compared with the normal dental formula for the species, and supernumerary
and congenitally missing teeth were identified and recorded. Agenesis was
observed in 0.93 % of the specimens analyzed (n = 10),
being more frequent in otariids. The posteriormost upper postcanines were the
teeth absent most frequently. Supernumerary teeth were observed in
1.8 % of the specimens (n = 19), more commonly in
phocids. Supernumerary teeth can be interpreted as either atavistic
manifestations (particularly for the posteriormost postcanines in Otariidae) or
cases of disturbances in dental morphogenesis leading to the formation of extra
teeth when they occur in other positions of the tooth row. Morphological dental
variants such as ectopic and geminated teeth were also recorded. Cases of
dental anomalies should have a limited effect on the functional morphology of
the feeding apparatus in pinnipeds, with little influence on the fitness and
performance of the animals. Nevertheless, understanding patterns of dental
variation should contribute to future studies aiming to elucidate aspects of
dental evolution and the phylogenetic relationships of pinnipeds.
Full text is available at:
http://link.springer.com/article/10.1007%2Fs00435-015-0255-x
Or alternatively, a pdf can
be requested at: carolina.loch@otago.ac.nz
Best regards,
________________________________________
Carolina Loch Silva, PhD
Postdoctoral Research Fellow
Sir John Walsh Research Institute
Faculty of Dentistry, University of Otago
Dunedin 9054, New Zealand
Phone: +(64) 03 479-5667
&
Research Collaborator
Geology Department, University of Otago
and
Laboratório de Mamíferos Aquáticos UFSC
Florianópolis, SC - Brasil
http://www.otago.ac.nz/geology/people/students/loch/index.html