Image Gallery: Lethal Aggression in Wild Chimpanzees

Walking around

Chimp walking around

(Image credit: Ian Gilby)

Chimpanzees are the only other known species, besides people, who will coordinate lethal attacks against others of their own kind. Chimps, like this alpha male, have helped researchers learn that human influences, such as deforestation, are not causing this violent behavior in the apes.

We hear you

Chimps listening to each other

(Image credit: John Mitani)

Adult male chimps from the Ngogo group gather together to listen to vocalizations from chimps in a rival community.

Portrait pose

Chimp portrait pose

(Image credit: Ian Gilby)

A photo of Titan, an adult male chimp from the Kasekela group. A new study on Titan and other chimps and bonobos found 152 killings among 22 ape groups over a period of many years.

Chimp charge

Chimp charge

(Image credit: Ian Gilby)

The alpha male Ferdinand of the Kasekela group stands on two legs during a charge display. Aggression is common in primates, but chimps can sometimes go a level above that and coordinate lethal attacks on each other.

Tree time

Chimp in tree

(Image credit: Ian Nicholas)

A chimpanzee calls down from a tree in the Goualougo Triangle in the Republic of Congo. Chimps in East Africa are more likely to kill one another than chimpanzees in West Africa, a new study found.

Lounging around

Republic of Congo chimp

(Image credit: Ian Nicholas)

Chimpanzees that live in the community in the Goualougo Triangle in the Republic of Congo show that although chimps can act violently, they also spend a lot of time together.