 A group whose ecology is characterized by things like frequent natural disasters, disease, territorial invasion, or resource scarcity is likely to possess a more comprehensive and exacting system of norms and to take a stricter stance towards its norms, in part because more efficiently coordinated social action is required to overcome more severe threats. Groups faced with less extreme ecological stressors have less dire need for tightly coordinated social action, and so can afford to have weaker norms and more tolerance for deviation.