Development of preference for baby faces across species in humans (Homo sapiens)

Previous studies have revealed that there is a close relationship between the strength of an infant's baby schema and the degree of its perceived cuteness. The present study investigated the development of preference for baby schema in humans by examining the recognition of the cuteness of baby faces; two studies were conducted to examine whether children's evaluation of cuteness differed from that of adults. Facial photographs not only of humans (Homo sapiens), but a chimpanzee (Pan troglodytes), rabbits (Oryctolagus cuniculus), dogs (Canis familiaris) and cats (Felis sylvestris catus) at different ages were used as stimuli. The volunteers were requested to rank these photographs in order of cuteness. Study 1 suggested that there was a range of period during which adults perceived the faces of these five species to be the cutest. Study 2 indicated that children's judgment of cuteness closely corresponded to that of the adults. In conclusion, the preference for baby schema is observed in humans even before they get to be sexually mature enough to reproduce. Childhood preference for baby schema might be the basis of social learning, including caretaking behaviors.