Baboon troop structure and the hierarchy

Image credit: Joselyn Mormile

Cape chacma baboons (Papio ursinus ursinus) live in family units, called troops, of around 20-80 individuals.

Troops are made up of several matrilines. Females remain in their natal troop for life and males leave their natal troop upon reaching sexual maturity to prevent inbreeding with related females.

It is all about rank and the females inherit rank!

There are both male and female hierarchies in a baboon troop. The highest-ranking position in the troop is that of the alpha male. This position, which males must heavily compete for, changes every few months to every few years. The alpha male has access to the best resources and is responsible for protecting the troop and keeping troop members in line.

Image credit: Joselyn Mormile

There is also an alpha female in the strict female hierarchy. Females inherit their rank from their mothers at birth, with each subsequent daughter inheriting the rank just below her mother and above her older sister. Unlike male rank, which is very flexible as males move in and out of the troop, female rank generally remains stable.

Written by Joselyn Elise Mormile
Ph.D. candidate, UCT