KIN RECOGNITION IN GOLDEN-HAMSTERS - EVIDENCE FOR PHENOTYPE MATCHING

We assessed scent marking by golden hamsters in response to flank glan d odours from kin and nonkin to investigate mechanisms of kin recognit ion by odour cues. Hamsters engage in two types of scent-marking behav iour, flank marking, which is associated with competition and aggressi on, and vaginal marking, which females use for sexual solicitation. In experiment I, flank marking by males and flank and vaginal marking by females was significantly less in response to flank odours from sibli ngs than nonsiblings. These results indicate a lower level of agonisti c motivation (flank marking),and sexual interest (vaginal marking) tow ards kin than nonkin. In experiment-2, the marking responses of males and females to flank odours from siblings, unfamiliar half-siblings an d unfamiliar nonsiblings were graded based on the degree of relatednes s. In experiment 3, males from cross-fostered lifters marked significa ntly less in response to flank odours from brothers than nonbrothers, regardless of whether they were reared with the odour donors. These re sults demonstrate a phenotype matching mechanism for kin recognition b ased on differences between odours from kin and nonkin. Because the-pr esence of foster-siblings or a foster-mother in the nest did not chang e hamsters' responses to flank odours from kin:versus: nonkin, one pos sible explanation for our results is that hamsters use their own odour -asa referent in this process ('self-referent phenotype matching'). (C ) 1998 The Association for the Study of Animal Behaviour.