Developmental process of cultural behaviors among wild chimpanzees
Report: NISHIE Hitonaru
Date: 2012/9/11 - 2012/11/9
I conducted a field research on wild chimpanzees of the M group at the Mahale Mountains National Park, Tanzania, from September to November 2012.
The aim of this study is to collect data on the following so-called 'cultural' behaviors among wild chimpanzees:
ant-fishing, a tool-using behavior for feeding on arboreal carpenter ants; pant-grunt, a greeting behavior
frequently observed in the situation of encounter; leaf-clipping, a courtship display mainly exhibited by adult and adolescent males.
I observed chimpanzees using adlib sampling and focal animal sampling methods and mainly focused on the
social interactions among the members of the group.
On ant-fishing, I accumulated new basic data such that some host trees of ants which were observed as
ant-fishing sites in 2002 are still, ten years later, used as ant-fishing sites by the M group chimpanzees, and that a newly immigrated female was observed to fish
for ants skillfully in her first days in the M group.
As for pant-grunt and leaf-clipping, I collected detailed behavioral data in the context of social interaction.