CRANIAL FORM AND SEXUAL DIMORPHISM IN THE IRISH OTTER LUTRA-LUTRA L
LYNCH JM , OSULLIVAN WM
BIOLOGY AND ENVIRONMENT-PROCEEDINGS OF THE ROYAL IRISH ACADEMY 93B (2): 97-105 JUN 1993

Abstract:
Sexual dimorphism in cranial size and shape was examined in a sample of adult otter (Lutra lutra) crania from Ireland. Univariate and multivariate techniques revealed a high degree of dimorphism, with shape, rather than size, accounting for most (86.96%) of the variation between the sexes. The results are discussed in relation to cranial musculature, dietary relationships between the sexes, and existing theories which try to explain the occurrence of sexual dimorphism in mustelids.