" When changes in one genetic trait are the source of selection for changes in a second, the rate of response in the latter depends in parts on the rate of change in the former, which, as a rule, is not fast. In comparison, if a cultural practice modifies selection acting on human genetic variation, then the greater the proportion of individuals in the population that exhibit the cultural trait, the stronger the selection on the gene. As a consequence, the rapid spread of a cultural practice often leads quickly to the maximally strong selection of the advantageous genetic variant, which rapidly increases in frequency. Cultural practices typically spread more quickly than genetic mutations, simply because cultural learning typically operates at faster rates than biological evolution. What does the speed with which a culturla trait spreads depend upon? Answer: the fidelity of cultural transmission. The very factor that is critical to the emergence of complex cumulative culture in humans is also a major determinant of evolutionary responses to that culture. "

― , Darwin's Unfinished Symphony: How Culture Made the Human Mind