Dartmouth anthropologist researches gelada monkey communication

(monkeys squeal) – This video clip that we’re looking at is a clip of an aggressive interaction between two male geladas living in the Simien
Mountains of Ethiopia. The rivalry here is based on a harem group structure
where only a single male mates with the females. The male on the right is the former leader of this harem and he is interacting with a male who would
become the new leader. The old leader is showing
a facial expression here that is typically used to request grooming of a friend and so he
seems to be communicating not only his submission to a
new social status in the group but also something even
more benign which is that I’m a friend and you
don’t have to worry about me. The interesting thing is
that the very next day the former leader disappeared
from this population of geladas and we never saw him again. It’s unlikely that he left
and went to another group but probably died.