The Evolutionary Psychology FAQ

Edward H. Hagen, Institute for Theoretical Biology, Berlin

How can evolutionary psychologists talk about adaptations without talking about specific genes?

Although adaptations evolved to facilitate the reproduction of the genes that code for the adaptation, not the reproduction of the organism bearing those genes, this important distinction leads to no difference whatsoever in the analysis of large categories of adaptations. In most cases, the reproduction of the organism is required for genetic replication. This is why Darwin was able to propose adaptationist explanations that still stand. Darwin--and scientists to this day--can, for the most part, avoid the currently intractable problem of the precise relationship between genes and complex adaptations and instead focus on the eminently tractable problem of the reproductive functions of the body and brain. Scientists can confidently address the functions of hearts, lungs, blood, and uteruses using evidence of design without knowing anything about the genes that code for these organs. The question becomes, not "did these traits facilitate the reproduction of specific genes," but rather, "did these traits facilitate the reproduction of the organism in the EEA?" Similarly, we can address the functions of the brain without knowing anything about the genes that underlie these functions. In fact, who can doubt that vision, hearing, smell, and pain--phenomena that rely critically on the brain--served crucial functions that facilitated the reproduction of the organism and its close relatives over evolutionary time?

If Darwin had known about genes, he would have been able to (among other things) modify the definition of adaptation to include functions that promoted the reproduction not only of the organism, but also of relatives of the organism (since they are likely to share some of the organism's genes). This modification allows evolutionary researchers to analyze an extremely large set of adaptations without ever having to refer to specific genes.

Copyright 1999-2002 Edward H. Hagen