Peeing is Contagious for Chimpanzees



For chimpanzees, the need to pee appears to be contagious. The phenomenon is called “contagious urination.” When chimpanzees in a sanctuary appeared to pee at roughly the same time, researchers became curious to see if urination could be similar to contagious yawning seen in humans. In more than 600 hours, scientists saw 1,328 instances of urination among 20 chimpanzees. They found that urination events were significantly more synchronized than would be expected if the animals were simply peeing at random times. The likelihood of contagious urination also increased if a chimpanzee was physically closer to the initial urinator. Chimps with lower ranks in the group were also more likely to pee when others were urinating. That suggests that urination patterns are influenced by social hierarchy. The results indicated that social closeness didn't have any effect on this action. Instead, social rank appeared to have the greatest influence, with lower-ranking chimps being more likely to follow. According to the team, it also shows how some seemingly mundane — yet absolutely necessary — behaviors may have an overlooked social significance.