Social Cooperation
Photo Courtesy of Dr. Pascal Ngoboka from Ngamba Chimp Sanctuary, Lake Victoria, Uganda
Sharing Food
Mothers will usually willingly share food with their infants under the ages of three. Chimpanzees over the age of four are usually not given foods that are easy to obtain, but mother’s will continue to share foods that are more difficult for their offspring to procure. Adults will only rarely share plants food, but meat is almost always shared. A possessor may share such a valued food if he simply has too much for him to finish himself. In this instance the chimpanzee would expend too much energy defending a resource he does not really need. Sometimes other chimpanzees beg for pieces of the meat so incessantly that the possessor shares simply to appease them. The possessor will usually tear off pieces to share and pass them to the begging individuals with his hand or mouth (Goodall, 1986).
Photo Courtesy of Jane Goodall Institute
Helping Behaviors
Altruistic behaviors seem most prevalent in instances of interactions with infants. Mothers will put themselves at risk to protect their infants, and infants will often try and help his or her mother if she is being attacked. This type of helping behavior extends to other members of the family as well. Adult sisters and juveniles will often come to the aid of a family member who is being attacked by an aggressive male. Sometimes adult males will help each other in defense against a more dominant male even when no known relatedness is present. Kin selection is responsible for helping behaviors among genetically related individuals, largely because kin have a strong sense of familiarity with one another. Goodall speculates that this strong sense of familiarity that can also exist among non-related chimpanzees may be responsible for the altruistic behavior observed when non-related individuals risk their own well being to help one another (1986).
Chimpanzees have the capacity to form lasting bonds, and they have good long-term memories. For these reasons instances of reciprocal altruism have also been documented (Trivers, 1971, as cited in Goodall, 1986). Sometimes chimps are even punished within their community for failing to return a good favor (de Waal, 1982, as cited in Goodall, 1986).