For a brief second, a young gelada female interrupts her foraging to stare into the camera. These Ethiopian monkeys have to eat throughout the day to obtain enough nutrients from their primary food source, alpine grass.
Two adult male geladas get into a loud fight over access to females. In the treacherous terrain of the Simien Mountains National Park these fights can sometimes be deadly.
Researcher Aliza le Roux records the vocalizations of gelada bachelors foraging in the tall grasses of Ethiopia's Simien Mountains National Park. These males spend years gaining strength, waiting for an opportunity to take over a group of females for themselves.
A relaxed gelada male stares down over the cliff edge as one of his many females grooms him. Down below, over a hundred gelada monkeys are slowly making their way to the top of the plateau in Ethiopia's Simien Mountains National Park.
Here a gelada baboon shows off his coarse, fluffy pelage, dark brown face and pale eyelids. Like other geladas, this one has a relatively short tail with a tuft at its tipo.
Gelada baboons make several communication calls, including a two-phase bark (deep, loud call repeated every few seconds), rhythmic grunts and shrill barks, which are single, explosive calls that serve as alarm calls.