de Waal, F. (1982) Chimpanzee politics: power and sex among apes. New York: Harper and Row. Introduction: The Arnhem chimp colony had about 25 individuals housed in an outdoor enclosure of almost two acres. Partially wooded, the enclosure has a mixture of live trees protected by electrical fencing and dead ones. Over a hundred recurring gestures and recurring signals have been observed in Arnhem, all of which have also been seen in the wild. One of the …showed first 75 words of 1458 total…

…showed last 75 words of 1458 total…Sharing is important. Once, the keepers gave a large pile of bananas to the troop. Yeroen behaved very aggressively in order to take control of the pile, but once he had it, he very carefully shared them out equally to everyone in the troop. Chimps will also cooperate, for example in escape attempts. Chimps also have a well-developed sense of reciprocity. They reward those who help them and punish those who act against their interests.