| Co-Investigator(Kenkyū-buntansha) |
UEMURA Kayoko Bunkyo Gakuin University, Dept. of Human Science, Professor (70213395)
HATAKEYAMA Hitoshi Bunkyo Gakuin University, Dept. of Veterinary Science, Assistant Professor (30350177)
TSUCHICA Asami Tokyo Agriculture Unviersity, Dept. of Agriculture, Sr. Asst. Prof (60439891)
HAMANO Sayoko Yamazaki Gakuen Collelge, Dept. of Animal Nursing, Sr. Asst. Prof (90413137)
|
|---|
| Budget Amount *help |
¥2,410,000 (Direct Cost: ¥2,200,000、Indirect Cost: ¥210,000)
Fiscal Year 2007: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000)
Fiscal Year 2006: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 2005: ¥900,000 (Direct Cost: ¥900,000)
|
|---|
| Research Abstract |
We have been observing infant chimpanzees and mothers at Tama Zoo, Tokyo, Japan since 2000 and have compared rearing style, child's development of exploratory behavior, social cognition and tool use acquisition. Zoo reared chimpanzees live in a stable conditions in terms of food supply and safe habituation. Therefore, once the mother chimpanzee is able to raise the infant, the survival rate is higher than the wild, that zoos with good social groups and enriched environment would provide a good observation field for child rearing behavior.
Our results show that better adapted mothers are more relaxed with the infant and allowing the infant to explore more, and a responding to child's needs, resulting in much higher exploratory behavior at 18 months. The onsets of tool use tend to be earlier for those as well. The acquisition of tool use, however may not be related to the earlier exploratory behavior. Hand preferences may be one of the factors, but we need more data.
While in wild, female leave the group, but under captivity, they may remain in the group and raise children, allowing us to compare mother-daughter rearing style. Well adapted mother's daughter showed similar behavior both in terms of exploratory behavior and also responding to child's needs. Nervous mother's daughter was much more relaxed in the group which she was raised in, but was not responding to child's needs.
Incidents of mother's refusal or unable to care for the baby are often reported in captive chimpanzees and possible causes are the early social isolation or early separation from the mother. We have examined all the birth cases on GAIN data base and have found that zoo raised chimpanzees which do not experience either early maternal separation or social isolation also have difficulties. With case studies of Tama zoo chimps, we speculate that early weaning and having sibling at much younger age may be involved in these difficulties.
|
