HUMAN-EVOLUTION AND THE CAPACITY TO CATEGORIZE

We have studied-with the help of a mathematical model of cultural tran smission-evolutionary effects which may derive from the appearance of a conceptual capacity to categorize behavior (approving or disapprovin g of it) in one of our hominid ancestors. We consider acquisition of b ehavior through individual learning and rudimentary cultural transmiss ion. The ability to categorize behavior produces an increase in the ef ficiency and the flexibility of the cultural transmission process. Mor eover, the capacity to categorize allows the acquisition, through cult ural transmission, of information about behavior, similar to that prov ided by individual learning (i.e., an individual's interaction with th e environment, in contrast to the receipt of lessons learned by others ) but avoids unnecessary costs by not having to resort to experience. An analysis of the model reveals that the advantage in terms of fitnes s in individuals capable of categorizing compared to individuals witho ut this ability increases the greater the difference in the intensity of cultural transmission between them and declines the greater the pro bability that behavior with adaptive importance can be developed witho ut the need of culture, that is, solely through individual learning. F inally, we suggest that intelligence has developed, within this framew ork of the cultural transmission, as a new system, outside the limbic- hypothalamic system, capable of generating values and showing preferen ces between different kinds of behavior.