Reproductive strategy and ethnic conflict: Slow life history as a protective factor against negative ethnocentrism in two contemporary societies.

Much previous theory and evidence in both social and evolutionary psychology has been equivocal and inconsistent regarding whether in-group altruism should predict out-group hostility, and whether this effect should be positive or negative in direction. A “slow” Life History (LH) strategy emphasizes both kin-selected altruism and reciprocal altruism as means of investing heavily in offspring, blood relatives, and mutualistic social relationships with both kith and kin. We therefore investigated whether a slow LH strategy, as a measurable individual-difference variable favoring in-group altruism (positive ethnocentrism), should predict out-group hostility (negative ethnocentrism), and what the direction of the hypothesized effect would be. We found that a multivariatelatent variable representing slow LH strategy served as a protective factor against a latent variable representing Negative Ethnocentrism. These results were replicated in the United States of America and in the Republic of Costa Rica using Multisample Structural Equation Model with cross-sample equality constraints.