ABSTRACT
T he idea that the human capacity for depressed mood evolved in responseto specific adaptive problems is by no means new. The argument enjoysa six-decade history (McGuire & Troisi, 1998), and has drawn contributions from a broad range of theorists (see Allen & Badcock, 2003). Generally, explanatory frameworks that have emerged from this expanding body of literature can be meaningfully grouped into two broad categories: explanations that emphasize the inherently social nature of the selection pressures that have shaped the human capacity for depression, and those that also focus upon non-social influences (Gilbert, 2006). We shall now consider each of these schools of thought in turn.
