抄録
A longitudinal study of chimpanzee infants at Tama Zoo in Japan revealed a relationship between the mother's rearing behavior and the exploratory behavior of the offspring. We observed 8 chimpanzees (born since 1999) for the first 36 months of their lives. We compared their motor development, tool use, and separation from their mothers. Nervous mothers tended to spend time away from the social group, isolating their infant at an early stage and making them more cautious about being away from their mother. Developmental diversities in social, physical and cognitive abilities were also observed. Some were early developers in general, while others were early in social and physical aspects but late in cognitive development, while some were slow in general. Further data is needed for a more detailed analysis. Life at the zoo is different from life in the wild, but observing young zoo animals allows us to gain developmental data that would be more difficult to obtain in the wild.
