The genetic underpinnings of right-wing authoritarianism and social dominance orientation explain political attitudes beyond Big Five personality

Objective: Political attitudes are predicted by the key ideological variables of right-wing authoritarianism (RWA) and social dominance orientation (SDO), as well as some of the Big Five personality traits. Past research indicates that personality and ideological traits are correlated for genetic reasons. A question that has yet to be tested concerns whether the genetic variation underlying the ideological traits of RWA and SDO has distinct contributions to political attitudes, or if genetic variation in political attitudes is subsumed under the genetic variation underlying standard Big Five personality traits. Method: We use data from a sample of 1987 Norwegian twins to assess the genetic and environmental relationships between the Big Five personality traits, RWA, SDO, and their separate contributions to political policy attitudes. Results: RWA and SDO exhibit very high genetic correlation (r = 0.78) with each other and some genetic overlap with the personality traits of openness and agreeableness. Importantly, they share a larger genetic substrate with political attitudes (e.g., deporting an ethnic minority) than do Big Five personality traits, a relationship that persists even when controlling for the genetic foundations underlying personality traits. Conclusion: Our results suggest that the genetic foundations of ideological traits and political attitudes are largely non-overlapping with the genetic foundations of Big Five personality traits

Trait-covariation, behavioral genetics and life history theory

In this chapter we critique evolutionary-developmental explanations of variation and covariation in psychological traits, with special emphasis on psychological ‘life history theory’. We argue that findings from behavioral genetics and developmental biology provides evidence that large proportions of individual differences in traits are caused by differences in genes, and differences in intrinsic randomness (and environmental damage) during embryo development. Further, behavioral genetic findings suggest that covariation between traits can often be attributed to genetic processes—such as pleiotropy and assortative mating—rather than the output of evolved mechanisms that use environmental cues. Overall, we argue that the relevant evidence leaves little room for evolved mechanisms that shape trait-levels and trait covariations in psychology

Attachment and political personality are heritable and distinct systems, and both share genetics with interpersonal trust and altruism

The attachment and caregiving domains maintain proximity and care-giving behavior between parents and offspring, in a way that has been argued to shape people’s mental models of how relationships work, resulting in secure, anxious or avoidant interpersonal styles in adulthood. Several theorists have suggested that the attachment system is closely connected to orientations and behaviors in social and political domains, which should be grounded in the same set of familial experiences as are the different attachment styles. We use a sample of Norwegian twins (N = 1987) to assess the genetic and environmental relationship between attachment, trust, altruism, right-wing authoritarianism (RWA), and social dominance orientation (SDO). Results indicate no shared environmental overlap between attachment and ideology, nor even between the attachment styles or between the ideological traits, challenging conventional wisdom in developmental, social, and political psychology. Rather, evidence supports two functionally distinct systems, one for navigating intimate relationships (attachment) and one for navigating social hierarchies (RWA/SDO), with genetic overlap between traits within each system, and two distinct genetic linkages to trust and altruism. This is counter-posed to theoretical perspectives that link attachment, ideology, and interpersonal orientations through early relational experiences

Causality and confounding between Right Wing Authoritarianism, education, and Socio-Economic Status; a twin study

While it is well-established that education and Right Wing Authoritarianism (RWA) are quite strongly negatively correlated, it is still unclear why this is the case. There could be causal effects between these variables, in one or both directions, which can be either direct or mediated. And there could also be confounding third variables influencing their association. Using a sample of 320 monozygotic- and 312 dizygotic twin pairs, we were able to control for confounding influences from both genes and the family-environment, increasing our ability to infer causal effects. Furthermore, we investigate the roles of perceived Socio-Economic Status (SES) in both childhood and adulthood; SES in childhood could be a confound between education and RWA, and SES in adulthood could be a mediator. We explore these hypotheses with ACE-β models, which extend the logic of discordant twin designs into a structural equation framework. Our results are consistent with a causal effect of education to reduce RWA. SES in adulthood did not mediate this effect. We find that the negative correlation between RWA and education is further amplified by confounding influences, mostly from the family environment, which are partly associated with SES

The genetic underpinnings of right-wing authoritarianism and social dominance orientation explains prejudice beyond big five personality

One of the most robust findings in political psychology is that political and prejudicial attitudes are predicted by right-wing authoritarianism (RWA), social dominance orientation (SDO), and some of the Big Five personality traits. An unresolved question is whether RWA and SDO form a functional package of traits that is independent of common personality variation, or whether they are fully underpinned by it. We use genetically informative data from a sample of 1987 Norwegian twins to shed light on this question, revealing that RWA and SDO are moderately phenotypically correlated, but highly genetically correlated. This suggests that there is a general, heritable hierarchical motive that manifests in terms of RWA and/or SDO depending on environmental factors. Consistent with this, RWA and SDO share a larger genetic substrate with political attitudes that support monopolizing resources and territory for one’s own group (e.g., deporting an ethnic minority) than do Big Five personality traits, while at the same time exhibiting some genetic overlap with two of these personality traits. Overall, these results suggest that Big Five personality traits are not sufficient for explaining prejudicial political attitudes and that the covariation of hierarchy-related traits with political attitudes is best explained by genetic overlap, not common socialization as assumed by key theories in social and political psychology, such as the dual-process model of prejudice

Intergenerational transmission of ADHD behaviors: More evidence for heritability than life history theory

Background: Parents and children resemble each other in ADHD behaviors. A key theoretical postulate from the evolutionary life history theory is that children use information from their environment (e.g., predictability and resource availability) and develop traits that are optimized for future success in that environment. Life history theory therefore expects that variation in children’s ADHD behaviors reflects evolved calibration to the developmental context that parents provide. Alternatively, children may resemble their parents not because of the provided environments, but because of their transmitted genes. Methods: We employed a large children-of-twins-and-siblings sample (N=22,350 parents & 11,566 8-year-old children) of the Norwegian Mother, Father and Child Cohort Study (MoBa). This enables disentangling intergenerational influences via parental genes and parental behavior (i.e., genetic and environmental transmission, respectively). Fathers reported on their symptoms (or absence thereof) and mothers on their own and their child’s symptoms. Results: Child ADHD behaviors correlated 0.24 with ADHD behaviors in mothers and .10 with those in fathers. These correlations were largely due to genetic transmission; genetic transmission was five times larger than environmental transmission. Variation in children’s ADHD behaviors was largely explained by heritability (57%), with small effects of parental ADHD behaviors (2% environmental transmission), and gene-environment correlation (3%). The remainder was due to unique environmental influences and noise. Conclusion: The intergenerational transmission of ADHD behaviors is primarily due to genetic transmission, with little evidence for parental ADHD behaviors causing children’s ADHD behaviors. This contradicts the life history theory. The child-specific variability in ADHD behaviors is due, in equal amounts, to genetic factors that influence children’s but not parents’ ADHD behaviors, and to environmental influences and noise that make siblings unique from one another. We conclude that ADHD is not the outcome of adaptive behavior to the (family) environment, but rather a neurodevelopmental disorder with a strong genetic basis