An overview of the basics of the entire field from the very important perspective of ecological genetics. A most relevant perspective for a balanced review of the mechanisms of the evolutionary process and its underlying theory. Merrell’s pluralistic approach to resolving evolutionary problems is commendable.

Merrell suggests that evolution takes place by many mechanisms, therefore no single one is the whole story. Although surely much of evolution is by slow Darwinian gradualism, there are mechanisms for rapid and even instantaneous change—polyploidy, for example. This plurality of mechanisms is a point well worth making! With this concept, Merrell suggests that Sewall Wright’s adaptive surface is more like the undulating surface of a seascape—the adaptive seascape—than it is like the usual model of a rugged landscape.