Male polygynous primates that fight with other males for females have much larger canines than male primates that are characteristically monogamous (Harvey, Kavanagh, and Clutton-Brock 1978). Character-environment correlations of this type are known as adaptations. They catch our attention because they seem so well designed for the job they perform.

DEFINE: This highlight introduces the concept of 'adaptations' — correlations between an organism's traits and its environment that appear designed for a function.

Diego Gambetta, Trust - Making and Breaking…, loc. 260