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A comparative review of condylobasal lengths and other craniometric characters in 30 species of pinniped

Published online by Cambridge University Press:  27 October 2009

E. Cruwys
Affiliation:
Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ
A.E. Friday
Affiliation:
Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ

Abstract

The condylobasal length (CBL) of skulls from 999 sexually mature seal, sealion, and fur seals of 30 different species was measured. Additional data gathered from previous studies were also included to give an indication of variation within each species, particularly where there is a wide geographical dispersion. Where possible, means and ranges of CBL were given separately for each sex, so that the degree of sexual dimorphism could be assessed. Previous studies have indicated that CBL continues to increase after sexual maturity has been reached. In order to assess this, three species (Mirounga leonina, Otaria byronia (flavescens), and Halichoerus grypus) that contained individuals of known age were included in the study. Other craniometric characters are often expressed as a percentage of CBL when assessing taxonomic relationships. Some of these characters were reassessed using the new data.

Type
Articles
Copyright
Copyright © Cambridge University Press 1995

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