Chimpanzees in Côte d'Ivoire's Taï National Park use hills to strategize, according to a recent study. They climb the hills to listen for rival group sounds and determine their distance. The further away the rival group, the more likely the chimpanzees invade their territory. This behavior suggests that chimpanzees have complex cognitive abilities and a possible link to early human warfare. The study highlights their strategic decision-making and cooperative behavior to avoid conflicts and secure territories, which is the first evidence of non-human animals using higher ground to monitor enemies.