Broude (psychology, Vassar) has produced a work that is more anthropological than psychological in nature, placing its emphasis on societal and tribal customs rather than on individuals' motivations. Broude uses the concept of sociobiology to explain why so many cultures have similarities in ideals-if not in the way these ideals are carried out. For example, in almost all cultures people will help their own kin before helping strangers, which Broude explains as an instinctive attempt by a person to make sure their genes (some of which are shared by their kin) survive. Similarly, Broude repeatedly explains the differences in male-female sex roles from an evolutionary perspective. Whether or not one agrees that biology is destiny, Broude makes a convincing case in several articles that this is a possible motivation for behaviors that occur across cultures.