Book review: Foraging with a prefrontal cortex makes all the difference

My cat is learning to catch squirrels in the back garden. It’s a painfully slow process. He seems to be trying every available technique, improving step by step. He’s tried sitting near the house and charging down the garden when a squirrel appeared, only for the squirrel to spot him and dash off. He’s tried assaulting the squirrel when it came down the tree, only to find out that squirrels climb faster than cats. He doesn’t seem to have an overview of the situation, grasping that his best strategy is to hide near the back fence, the only place where he can sneak up on the squirrel and cut off its escape route. Why isn’t he capable of that seemingly simple strategic inference? A new book by Passingham andWise (2012) provides a possible answer: because he doesn’t have the large, primate prefrontal cortex (PFC). Passingham and Wise (2012) set out to understand the organization and function of the primate PFC by combining evolutionary and ecological perspectives. Large parts of PFC, and specifically those with a granular cortical layer, are a primate invention. The authors argue that the development of these areas reflects the changes in foraging niches encountered during the evolution of the primate order. There is a large body of work relating aspects of brain evolution to specific ecological variables, most notably foraging habits (Clutton-Brock and Harvey, 1980) and social organization (Dunbar, 1998). However, these studies have mostly focused on the relative size of the entire brain or neocortex. In contrast, work dealing with more detailed brain anatomy has tended to focus less on the evolutionary context. The unique contribution of this book is that it combines the two approaches without compromises, focusing on a detailed reconstruction of the ecological challenges encountered by the primate brain and the anatomical information that provides avenues to understanding how these challenges have been met.