Age determination on teeth of Otariidae and Phocidae (Carnivora), alternative techniques.

The periodic depositing of layers of cement and dentine on the mammal?s teeth it is very useful to determine the absolute age. The different events produced during the life cycle as moult, sexual maturity, nursing and feeding are reflected on the amount and type of cement and dentine deposits on the...

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Bibliographic Details
Published in:Revista del Museo de La Plata
Main Authors: Loza, C. M., Soibelzon, Leopoldo H., Tarnawski, B. A., del Corrro, M. E., Negrete, Javier, Ciancio, Martín
Format: Article in Journal/Newspaper
Language:Spanish
Published: Facultad de Ciencias Naturales y Museo - Universidad Nacional de La Plata 2016
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Online Access:https://publicaciones.fcnym.unlp.edu.ar/rmlp/article/view/5
https://doi.org/10.24215/25456377e005
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Summary:The periodic depositing of layers of cement and dentine on the mammal?s teeth it is very useful to determine the absolute age. The different events produced during the life cycle as moult, sexual maturity, nursing and feeding are reflected on the amount and type of cement and dentine deposits on the teeth. The aim of this contribution is to determine through the application of different techniques the age of specimens of Phocidae and Otariidae (Mammalia) housed on different collections in Argentina; in order to compare the results obtained with the use of different techniques and to incorporate a crucial datum to each studied specimen. The different techniques were tested, improved and then were performed on 335 specimens of Arctocephalus gazella, Arctocephalus australis, Otaria byronia, Mirounga leonina, Leptonychotes weddellii, Lobodon carcinophagus e Hydrurga leptonyx. The techniques used were: root external rings counting, dentine and cement line counting, both undecalsified as decalsified. Our results showed that not all techniques are effective for all species and for all teeth, effectiveness depends i.e. on the teeth size, on the way on the cement is deposited. Finally, we recommend which techniques are more effective for each species. The external ring and dentine line counting techniques with and without decalsification are more suitable for Arctocephalus, the dentine line counting by decalsification is recommendable for O. byronia, while in focids is better to used the line cements counting with previuos decalcificaction in postcanines. La depositación periódica de capas de esmalte, cemento y dentina en los dientes de los mamíferos es de gran utilidad para la determinación de edades absolutas. Los diferentes sucesos que se producen durante la vida del animal como la muda, la madurez sexual, período de lactancia y de alimentación, se reflejan muchas veces en la cantidad y tipo de depósito de dentina en las piezas dentarias. Los objetivos de este trabajo son: determinar, con diferentes técnicas ...