LIFE-HISTORY THEORY AND HUMAN REPRODUCTIVE-BEHAVIOR - ENVIRONMENTAL CONTEXTUAL INFLUENCES AND HERITABLE VARIATION/

The purpose of this article is to develop a model of life history theo ry that incorporates environmental influences, contextual influences, and heritable variation. I argue that physically or psychologically st ressful environments delay maturation and the onset of reproductive co mpetence. The social context is also important, and here I concentrate on the opportunity for upward social mobility as a contextual influen ce that results in delaying reproduction and lowering fertility in the interest of increasing investment in children. I also review evidence that variation in life history strategies is influenced by genetic va riation as well. Finally, I show that cultural shifts in the social co ntrol of sexual behavior have had differential effects on individuals predisposed to high-versus low-investment reproductive strategies.