Baboons move in groups of about 80 individuals for defense. Often, larger males will go on offense as well -- chasing away predators or taking down a young gazelle.

Each spring, the eland must climb the sheer cliffs of the Drakensberg to reach the new grass on the plateau. Watch the full episode now.

For baboons, grooming is a highly pleasurable activity. The pulling of hair releases endorphins.

When a large male from a neighboring troop chases off the dominant male of the invaded troop, chaos ensues.

(Airs Sunday, August 9) Amid the wilderness of Africa's Zambezi region unfolds a sinister tale of political upheaval, sexual intrigue, and murder in a community of chacma baboons.

Whether they involve defending each other or offering gentle and nurturing support, one thing is certain -- friendships are vital to chacma baboon society.

View additional resources, online and in print, for NATURE's "Murder in the Troop."

Among the most highly socialized of all animal species, chacmas rely on a complex and varied communication system with visual signals, vocal gestures, and body language.

Chacma baboons draw upon a rich repertoire of vocal signals to express themselves.

Adult male chacmas have earned a "tough guy" reputation. Visually assertive displays may serve to get a message across before a physical brawl occurs.