HIN RECOGNITION IN THE COMMON LIZARD

The ability to recognize parents has never been reported in species in which parents do not provide care to their young; in such species, on ly sibling recognition has been found. However, there may be several a dvantages of parent recognition, even in the absence of parental care. We investigated the ability of neonates to recognize olfactory cues f rom both their mother and siblings in the common lizard, Lacerta vivip ara, a species without parental care. Juveniles from 264 gravid female s were reared for 2 days either with their mother, with another female , or separated from all other adults. Juveniles from some families wer e split into two or three groups so that each juvenile was unfamiliar with a subset of its siblings. After 2 days, we offered the juveniles a choice of two nocturnal shelters: one containing a lizard odor and t he other without odor. The response to the odor of an unrelated and un familiar adult was influenced by both the sex of the adult and the sex of the juvenile. Juveniles of both sexes recognized the odor of their mother whether they were familiar with her or not (pre-natal determin ism). Juveniles recognized familiar but not unfamiliar siblings (post- natal determinism). In the wild, spatial association with kin declines shortly after birth. Thus, recognition of the mother is likely to hav e biological relevance. Recognition of the mother may reduce competiti on and/or enhance juvenile establishment.