Aurelio J Figueredo et al.; December 2013
Journal of Social, Evolutionary, and Cultural Psychology
The Strategic Differentiation-Integration Effort (SD-IE) hypothesis predicts regulation by life history speed (K) of the magnitudes of the correlations among its components, such that individuals with slower life history strategies exhibit life history traits that are less correlated with each other than individuals with faster life history strategies. This conative differentiation among high-K individuals is proposed to arise due to the elevated social competition in stable, predictable environments faced by these individuals and to facilitate mutualistic rather than antagonistic social interaction strategies via social-ecological niche-splitting and domain-specific resource allocation. We tested the predictions of SD-IE regarding relations among life history traits using the Continuous Parameter Estimation Method on data from two college student convenience samples, one all-female sample (N=382) and one mixed-sex sample (N=205), as well as two nationally-representative samples of the US population, the MIDUS (National Survey of Midlife Development in the United States, N=2080) and the NLSY (National Longitudinal Survey of Youth, N=5082). The predicted SD-IE effects were statistically significant and in the expected negative direction among most indicators of the lower-order slow life history factors and among all indicators of the single higher-order slow life history Super-K factor.