One day when I was volunteering at the Chimpanzee Human Communication Institute in Ellensburg, Washington, where Washoe (the famous chimpanzee trained in American Sign Language) and her family live, an argument broke out between the chimps. At the time there were 4 chimps living in the facility, in order of dominance rank: Washoe, her adopted son Loulis, Tatu, and Dar. I was in the observation area recording their independent, seemingly peaceful, behaviour for a paper project conducted by Dr. Mary Lee Jensvold when the tension broke out and chaos ensued. The chimps were screaming loudly, jumping from platforms to the ground, and swinging on fire hoses and tires hung around the enclosure for enrichment; toys and magazines (other enrichment items) were being thrown around as they chased each other around their enclosure. It was an intense moment and all of us humans just observed in awkward silence. I remember everyone stopped what they were doing. A few volunteers and staff were s