The psychology of cooperation: Insights from chimpanzees and children.

Across all cultures, humans engage in cooperative activities that can be as simple as preparing a meal or sharing food with others and as complex as playing in an orchestra or donating to charity. Although intraspecific cooperation exists among many other animal species, only humans engage in such a wide array of cooperative interaction and participate in large-scale cooperation that extends beyond kin and even includes strangers. [ABSTRACT FROM AUTHOR]