The elastic between genes and culture

A society's culture may come to include information tending to lead to fitness-reducing behavior on the part of some or all of its members. This phenomenon results from conflict among factions within each society, from transmitted misinformation (e.g., cupping restores health), from natural and human-caused environmental change so that previously adaptive information becomes maladaptive, and from the long and short-term negative “side effects” of information that may otherwise be fitness enhancing. Because some cultural information may be fitness reducing, we apparently have been selected for individual-level traits that often result in our revising socially transmitted information that might otherwise have maladaptive consequences. Two examples of such traits are adolescent “rebelliousness” and the tendency to learn most readily from those higher than ourselves in status. Such leading-to-culture-revision traits are very imperfect mechanisms, however, so that some likely-to-be maladaptive cultural information, such as medical cupping or denying infants the colostrum, remains part of the culture. It is doubtful, given the structure of modern human populations and the ubiquity of culture change, that such maladaptive socially transmitted information leads to natural selection for genetic “direct biases” against accepting the practices in question.