A theory of social stratification is proposed that was derived from combining two conceptual continuums, both referring to phenomena that appear to be genetically influenced: pro/antisociality and r/K selection. Pro/antisociality refers to behavioral tendencies epitomized at one end by altruism, and, at the other end, by victimizing behavior (particular violent offenses). r/K selection refers to a variety of physiological and behavioral traits, epitomized at the r-end by organisms that reproduce in large numbers, while committing minimal time and energy to the nurturing of each offspring, and at the K-end by organisms that reproduce in small numbers, but make maximum commitments to nurturing each offspring. The theory postulates that the space created by the right-angle intersection of these two variables gives rise to human social stratification. Variations in educational achievement, earnings, and occupational prestige within the theoretical space created by these two variables in industrial societies are hypothesized and discussed.