If you’re not worried by the war, you’re not paying attention. No, not the war in the Middle East. The war in Africa. The Red Cross says there are more than 50 active conflicts in Africa right now. But the only one that interests our media is a civil war in Uganda between two troops of chimpanzees.

For over 30 years, primatologists have studied the world’s largest known group of wild chimps, the Ngogo group, in the rainforest of the Kibali National Park in northwestern Uganda. By 2015, there were nearly 200 Ngogos, living in what the primatologists described as harmonious “clusters.” One day, however, fellow primate Aaron Sandel of the University of Texas at Austin witnessed the larger Central cluster attacking the smaller Western cluster. The next few years saw an increase in what NPR’s Nathan Rott called “polarization.”