Cultures can be distinguished as tight and loose in relation to how much they adhere to social norms and tolerates deviance. Tight cultures are more restrictive, with stricter disciplinary measures for norm violations while loose cultures have weaker social norms and a higher tolerance for deviant behavior. A history of threats, such as natural disasters, high population density, or vulnerability to infectious diseases, is associated with greater tightness. It has been suggested that tightness allows cultures to coordinate more effectively to survive threats.