To observe the aging of wild chimpanzee
Date:2009/06/23 - 2009/09/16
In Bossou in Republic of Guinea, there are only one group with only 13 chimpanzees.
In this group, almost half of the members are estimated to be around 50 years of age.
They do not scare people so much.
For those reasons it is suitable to observe the aging of wild chimpanzees.
But for the same reasons, this group is facing with the risk of end.
Mainly older chimpanzees around 50 years of age were observed to examine how their physical activities and social relationships were.
Video and photograph of chimpanzees were taken by the guides in Bossou.
All of them seemed to have farsightedness (presbyopia) when they groomed others.
Some of them seemed to have arthritis of knees, and their standing postures were changed.
Some of them seemed to be easy to get tired but they could climb trees to eat and also to take rest.
The amount of activities, the amount of the food taking seemed to be decreased.
But this time there were no difference of the varieties of food they were taking between older chimpanzees and younger chimpanzees.
Chimpanzees were separated in small groups because of the shortage season of food.
I also confirmed the work of 'the Green Corridor' project of making forest between Bossou area and Mt.Nimba.