Behavior and the General Evolutionary Process

Behavior analysis is properly part of evolutionary biology, because only evolutionary theory can explain the origins of behavior and because behavior analysis follows the same mode of explanation as evolutionary theory. The resemblance among operant shaping, cultural evolution, and genetic evolution appears clearly only in the light of a general concept of evolutionary process. Every evolutionary process consists of three elements: variation, recurrence, and selection. Evolutionarily significant variation occurs among substitutable variants within a pool. These variants are defined by differences in their environmental effects. Although the metaphor of copying characterizes recurrence in genetic evolution, replication is only one type of recurrence. In cultural and operant evolution, mechanisms like stimulus control and induction cause the recurrence of the variants. Selection occurs when recurrence is differential. Differences in environmental effects produce differences in recurrence, and those differences feed back to affect the composition of the pool of variants. This general view of evolutionary process clarifies the distinction between proximate and ultimate explanations of behavior. Genetic, cultural, and operant evolution all admit of this distinction, because they all distinguish advantageous mechanisms from a history of advantage. Proximate explanations deal with the ?expression? of variants, whereas ultimate explanations deal with the feedback from environmental effects to the frequencies of variants in the pool. The three evolutionary processes may be seen as nested: cultural evolution within genetic evolution, and operant evolution within cultural evolution. A complete understanding of human behavior requires constructing six types of explanation: proximate and ultimate explanations in all three processes