Chimpanzees are regularly referred to as being one of the more human-like members of the animal kingdom. They’ve been taught sign language and, like humans, have a curved spine. Some sub-species use tools for hunting, and the bonobos — a “cousin” of the chimp (same genus and often also referred to as a chimp) have even learned to play video games.
And they go to war — over land.
Researchers in Uganda spent a decade observing chimp behavior, and recorded 21 chimp-on-chimp murders — 18 of which were directly observed. Said researcher John Mitani, from the University of Miami:
“The take-home is clear and simple. Chimpanzees kill each other. They kill their neighbors. Up until now, we have not known why. Our observations indicate that they do so to expand their territories at the expense of their victims.” What’s their motivation? Food, almost certainly — more land means more stuff to eat. But also procreation, as a wider territory means more potential mates.
And, as another study suggests, they understand death on an emotional level, mourning the loss of others in their community.
From the Archives: Monkeys are kind of scary, given the above — but velociraptors? Turns out, they were mostly harmless.
Related: A banana phone for your iPhone.