MOTHER-OFFSPRING RECOGNITION IN 2 AUSTRALIAN LIZARDS, TILIQUA-RUGOSA AND EGERNIA-STOKESII

Kin recognition has been reported in many animal taxa, but rarely in l izards. Newly born clutches from two viviparous Australian skink speci es, Tiliqua rugosa and Egernia stokesii, were either left with their m others, separated at birth and kept with a foster mother, or kept comp letely isolated from any adults. In experimental trials mothers were p resented with their own and with non-related young in gauze bags, and their attention to each young lizard was measured by the number of dir ected tongue flicks and the time in contact. There was a consistent te ndency in both species for mothers to direct more attention to their o wn young, whether they had been kept together or apart. Foster mothers directed more attention to their own non-familiar young than to their familiar foster young. In reciprocal experiments, young lizards of bo th species consistently directed more attention to their own mothers t han to unrelated females, even when they had been isolated from their mothers from birth. Olfactory cues are probably important for recognit ion. Using these cues, lizards can recognize kin, and discriminate bet ween kin and non-kin even if the latter have been in close association . It was not possible to determine if the discrimination was genetical ly based, or if it was acquired during or shortly after birth. The pre sence of mother-offspring recognition suggests that family groups may be a component in the social organization of these species. (C) 1996 T he Association for the Study of Animal Behaviour