Candace Jasmine Black

Methodologically Sound: Evaluating the Psychometric Approach to the Assessment of Human Life History [Reply to Copping, Campbell, and Muncer, 2014]

Copping, Campbell, and Muncer (2014) have recently published an article critical of the psychometric approach to the assessment of life history (LH) strategy. Their purported goal was testing for the convergent validation and examining the psychometric structure of the High-K Strategy Scale (HKSS). As much of the literature on the psychometrics of human LH during the past decade or so has emanated from our research laboratory and those of close collaborators, we have prepared this detailed response. Our response is organized into four main sections: (1) A review of psychometric methods for the assessment of human LH strategy, expounding upon the essence of our approach; (2) our theoretical/conceptual concerns regarding the critique, addressing the broader issues raised by the critique regarding the latent and hierarchical structure of LH strategy; (3) our statistical/methodological concerns regarding the critique, examining the validity and persuasiveness of the empirical case made specifically against the HKSS; and (4) our recommendations for future research that we think might be helpful in closing the gap between the psychometric and biometric approaches to measurement in this area. Clearly stating our theoretical positions, describing our existing body of work, and acknowledging their limitations should assist future researchers in planning and implementing more informed and prudent empirical research that will synthesize the psychometric approach to the assessment of LH strategy with complementary methods.

Strategic differentiation and integration of genomic-level heritabilities facilitate individual differences in preparedness and plasticity of human life history

Life history (LH) strategies refer to the pattern of allocations of bioenergetic and material resources into different domains of fitness. While LH is known to have moderate to high population-level heritability in humans, both at the level of the high-order factor (Super-K) and the lower-order factors (K, Covitality, and the General Factor of Personality), several important questions remain unexplored. Here, we apply the Continuous Parameter Estimation Model to measure individual genomic-level heritabilities (termed transmissibilities). These transmissibility values were computed for the latent hierarchical structure and developmental dynamics of LH strategy, and demonstrate; (1) moderate to high heritability of factor loadings of Super-K on its lower-order factors, evidencing biological preparedness, genetic accommodation, and the gene-culture coevolution of biased epigenetic rules of development; (2) moderate to high heritability of the magnitudes of the effect of the higher-order factors upon their loadings on their constituent factors, evidencing genetic constraints upon phenotypic plasticity; and (3) that heritability of the LH factors, their factor loadings, and the magnitudes of the correlations among factors, are weaker among individuals with slower LH speeds. The results were obtained from an American sample of 316 monozygotic (MZ) and 274 dizygotic (DZ) twin dyads and a Swedish sample of 863 MZ and 475 DZ twin dyads, and indicate that inter-individual variation in transmissibility is a function of individual socioecological selection pressures. Our novel technique, opens new avenues for analyzing complex interactions among heritable traits inaccessible to standard structural equation methods.

Parasite stress, ethnocentrism, and life history strategy.

Fincher & Thornhill (F&T) present a compelling argument that parasite stress underlies certain cultural practices promoting assortative sociality. However, we suggest that the theoretical framework proposed is limited in several ways, and that life history theory provides a more explanatory and inclusive framework, making more specific predictions about the trade-offs faced by organisms in the allocation of bioenergetic and material resources.

Substance, History, and Politics

The aim of this article is to examine the relations between two approaches to the measurement of life history (LH) strategies: A traditional approach, termed here the biodemographic approach, measures developmental characteristics like birthweight, gestation length, interbirth intervals, pubertal timing, and sexual debut, and a psychological approach measures a suite of cognitive and behavioral traits such as altruism, sociosexual orientation, personality, mutualism, familial relationships, and religiosity. The biodemographic approach also tends not to invoke latent variables, whereas the psychological approach typically relies heavily upon them. Although a large body of literature supports both approaches, they are largely separate. This review examines the history and relations between biodemographic and psychological measures of LH, which remain murky at best. In doing so, we consider basic questions about the nature of LH strategies: What constitutes LH strategy (or perhaps more importantly, what does not constitute LH strategy)? What is gained or lost by including psychological measures in LH research? Must these measures remain independent or should they be used in conjunction as complementary tools to test tenets of LH theory? Although definitive answers will linger, we hope to catalyze an explicit discussion among LH researchers and to provoke novel research avenues that combine the strengths each approach brings to this burgeoning field.

Evolutionary Perspectives of Personality

Evolutionary psychology is an important meta-theoretical paradigm for understanding universal and sex-differentiated adaptations. Despite this, it remains somewhat ignored within the mainstream study of individual differences. We outline some of the evolutionary approaches that lend to a fuller understanding of individual differences related to personality psychology. This chapter is presented in four main sections: (1) a brief summary of trait-based approaches that have been used to understand human personality, (2) an introduction to some of the evolutionary principles important to understanding behavior, (3) an explication of the function of individual differences within populations and the evolutionary mechanisms that produce such variation, and (4) a review of contemporary evolutionary models of individual differences with particular focus on personality traits.