Shimada / Poster

A Study plan of gene flow between Chimpanzee group at Bossou and others.

Makoto K. SHIMADA

     The primary forest intensively used by a chimpanzee group at Bossou, which have been studied since 1976 by a research team of KUPRI (Kyoto University, Primate Research Institute), is rather small (about 1km²) and does not connected with other primary forest. The home range of Bossou group is about 10 km² and located in peripheral area of Nimba Mountain forests. About five-km distance with savanna area separates both forests. According to the demographic record of the group since 1976 (Sugiyama 1999), the remaining rates of infant and juvenile (64 - 80 % for both sexes) are different from those of adolescents (14% for male, 33% for female). As a result, most of the individuals born in Bossou group disappeared from the group before maturation. On the contrary, the record of immigration shows only one male immigrant, two visitor males, and no female immigration. Sugiyama (1999) discussed that the migration pattern of Bossou group is different from those of other wild groups showing male-related group. The habitat circumstance and the demographic record suggest a potential threat of genetic deterioration of the wild chimpanzee group. The purpose of this study is to reveal the degree of gene flow between Bossou group and groups in the Nimba Mountains.
     I surveyed Nimba Mountains from three approaches, and confirmed existence of chimpanzee group at each of the three sites in Nimba Mountains. I corrected hair samples from chimpanzee groups at Bossou and Nimba Mountains for following research plan. I will 1) compare the genetic variability of Bossou group and other groups already investigated (Gombe group: Morin et al., 1994; Tai group: Gagneux et al., 1999), and 2) estimate the genetic relationship between Bossou group and groups in the Nimba using genetic markers.