Cultural Evolution

SYNOPSIS. Culture is made possible by the existence of mechanismsof learning and communication. Because of it, we can profitfrom the experience and ideas of others. It is convenient toinclude in it tools, technologies, and all culturally transmittedbehaviors. At least from an evolutionary point of view, theyshare common mechanisms. It is also becoming increasingly clearthatanimals share with us potential for cultural adaptation, whichis however much more highlydeveloped in humans, as shown forinstance, by the extension of human brain areas that are involvedin control of hand and phonation organs. To understand how culture evolves one can make resort to modelsthat map reasonably well after the necessary substitutions,into those that havebeen useful in biology. A major differencethat one finds is in mechanisms of transmission, which are muchmore varied in culture than in biology. Parent-child (vertical)transmission is present in both. An "infectious" (horizontal)mechanism is characteristic of cultural transmission, but ispractically absent in the genetic case. Other mechanisms oftransmission are reviewed, along with their evolutionary consequences.The variety of these mechanisms can make culture extremely fastand flexible, and there are the great advantages of culturaladaptation vs. genetic adaptation by natural selection, or vs.physiological adaptations (which are relatively fast but highlyspecific: for instance, tanning under exposure to UV). But culturecan also be extremely conservative. Also, some cultural transmissionmechanisms allow heterogeneitybetween individuals to persist,others tend to make populations extremely homogeneous. The study of culture from an evolutionary point of view is young,but very promising.