Social grooming among primates plays a significant role in animal consolation behavior in which individuals engage in establishing and maintaining alliances through dominance hierarchies. It cements pre-existing coalitions, and is used for reconciliation after conflicts. Primates groom socially in moments of boredom as well, and the act has been shown to reduce tension and stress. This video clip depicts Japanese macaques grooming each other at the Jigokudani Monkey Park in Japan.Photograph credit: Frank Schulenburg