Kin recognition in golden hamsters: evidence for kinship odours

Differential treatment of kin and non-kin has been well documented, but much remains unclear about how kin are recognized. If kin are recognized by a phenotype-matching mechanism, there must be a correlation between genetic relatedness and the similarity of cues used for recognition. A habituation technique was used with golden hamsters,Mesocricetus auratus, to investigate the relative similarity of the odour quality of flank gland secretions from siblings and unrelated individuals. Hamsters discriminated between the odours of their own, same-sex siblings but also treated these odours as similar compared to odours of non-siblings (experiment 1). They did not discriminate between the flank gland odours of unfamiliar siblings from another family (experiment 2). They also did not discriminate between the flank gland odours of unfamiliar, paternal half-siblings from another family (experiment 3). These results indicate that subjects perceived odours from genetically similar individuals as similar and provide evidence for kinship odour cues. The discrimination between the flank gland odours of subjects’ own siblings, however, indicates that hamsters learn the subtle differences between the odours of their close kin, probably through experience with siblings in the nest. When only volatile components from flank gland secretions were available to subjects (experiment 4), they again discriminated between the odours of their own siblings, suggesting that the volatile components from the flank gland secretion were sufficient for recognition of individual litter-mates.