Testing the cognitive niche hypothesis with structural equation modeling: different dark traits predict an evening-chronotype in males and females.

Dark triad (DT) refers to a set of antisocial and self-interested personality traits (Machiavellianism, sub-clinical psychopathy and narcissism). The nocturnal cognitive niche hypothesis suggests that the DT was advantageous in a nocturnal niche because it enables exploitative strategies and would be linked with an evening-oriented chronotype as part of a fast life history strategy. In the present self-report study (N = 300), this hypothesis was tested in a Brazilian sample. It was found that Machiavellianism was a predictor of this chronotype profile in females and secondary psychopathy was a predictor of this profile in males. Also, sex differences were replicated: on average, males exhibited "darker" personalities and more evening-oriented chronotype. Finally, these associations were tested with structural equation modeling controlling for sex and was found that the exploitative "darkcore" (psychopathy and Machiavellianism) predicts an evening-oriented chronotype. These results provide the first support for the nocturnal cognitive niche hypothesis in a non-WEIRD population. [ABSTRACT FROM AUTHOR]