Intelligent design in cultural evolution

Intelligent design, though unnecessary in the study of biological evolution, is essential to the study of cultural evolution. However, the intelligent designers in question are not deities or aliens but rather humans going about their lives. The role of intentionality in cultural evolution can be elucidated through the addition of signaling theory to the framework outlined in the target article. Darwinian aspects of cultural evolution were first identified long ago (e.g., Schleicher 1863). Mesoudi et al. update this analogy and make a convincing case for a unified science of cultural evolution that parallels the science of evolutionary biology. However, as Mesoudi et al. acknowledge, such a science must differ from evolutionary biology in a number of ways. One important difference, which they deal with quickly, is the active, often intentional role that humans play in cultural transmission and, thus, in cultural evolution. Although the notion of intelligent design is unnecessary in the study of biological evolution, it is essential to the study of cultural evolution. The intelligent designers in question, however, are not deities or aliens but rather humans going about their lives. When they do address the active role that individuals play in cultural transmission, Mesoudi et al.’s interest in long-term cultural evolutionary trends leads them to focus on technological innovation and creativity. They are correct that the impact of human intentionality on long-term cultural change in those realms is an empirical question and that recognition of intentionality does not undermine the approach they advocate. But those of us who live, work, and study in the here-and-now, minute-byminute, day-by-day, down-and-dirty, nitty-gritty reality of everyday human social life are constantly faced with the fact that the cultural pools in which we swim are at least stirred, if not created, by human intentions. When we study cultural change and other human phenomena on the short timescales of everyday life, grand analogies between biological and cultural evolution tend to become less interesting than the question of how our evolved psychological and behavioral propensities play themselves out in the things we say and do. Furthermore, even very drastic cultural change is possible on short timescales, and even if such episodes can be phrased in the language of cultural evolution, it is not clear what is gained by doing so. For example, I have documented a brief episode of extreme culture change among the Mukogodo of Kenya (Cronk 1989; 2002; 2004). In the space of little more than a decade, the Mukogodo shifted from speaking a language called Yaaku, living in caves, hunting, and keeping bees to speaking Maa, living in houses, and keeping livestock. This was surely an instance in which a particular meme pool was drained and refilled in short order, but pointing that out seems much less interesting than exploring the reasons why Mukogodo individuals chose to make such a swift and radical change. Those reasons certainly do involve the question of what memes they had available to them – they adopted those of their new neighbors rather than inventing entirely new ones or adopting those of some more distant group – but they also concern the strategies Mukogodo individuals employed to obtain food, find mates, communicate, keepwarm at night, stay dry when it rained, gain respect, and so on. One interpretation of this argument might be that even if cultural evolutionary theories like those described by Mesoudi et al. are relevant to long timescales, human phenomena at shorter timescales are best studied using non-evolutionary methods. I reject that interpretation and seek instead a way to remain within an evolutionary framework while focusing on phenomena that people experience in their everyday lives. Elsewhere (Cronk 1991; 1994; 1995; 1999; 2005) I have argued that this can be accomplished by using animal signaling theory to study signals that humans construct primarily out of the cultural raw materials