Comparison of skull measurements and sexual dimorphism between the Minorcan pine marten (Martes martes minoricensis) and the Iberian pine marten (M. m. martes): A case of insularity

The sub-species Martes martes minoricensis was described using craniometric data being larger in size than populations living on the European continent ( M. m. martes ). A new sample of 39 animals (22 males and 17 females) of this sub-species from Minorca was pooled by sex and age, and 26 craniometric variables were analysed and compared with 104 Iberian pine martens (73 males and 31 females). Age was determined through readings of the cementum layers of the teeth, enabling distinctions to be made between adult and young animals. Further data is shown regarding the characterisation of the sub-species in terms of these measurements and its sexual dimorphism for these variables. The values obtained enable us to identify the larger size of the Minorcan individuals, both males and females, in relation to those from the mainland, there being a development in the longitudinal characters of the facial bones. With regard to sexual dimorphism, the differences are similar to those found on the continent, males being on average 10.6% larger than females. However, we also found notable differences at the level of the facial bones. Some hypotheses regarding this segregation between the sexes and the larger size of individuals in relation to continental populations are discussed.