Preprint "Effects of male testosterone and its interaction with cortisol on self- and observer-rated personality states in a competitive mating context"

Increases in human male testosterone (T) levels have been found after intrasexual competitions and exposure to females, facilitating competitive and courtship behaviours. This suggests that T reactivity should affect relevant personality state changes that are also observable to others. How exactly T reactivity, also under potential buffering effects of Cortisol (C), relates to personality state changes is unclear. In a preregistered study, we aimed at inducing T increases in young men (N=165) through dyadic intrasexual competitions while exposed to a female experimenter. We investigated self-reported and video-based observer-rated personality state changes, as captured by the Interpersonal Circumplex and social impressions, in relation to hormonal levels. Results revealed increases in self-reported competitiveness, as well as observer-rated dominance and self-assurance, relative to a control group and moderated by T reactivity and partly by TxC interactions. Thus, male T reactivity in a competitive mating context increased competitiveness/dominance, but did not decrease nurturance. This provides further insights into how hormonal and personality responses to challenges are intertwined in men, and partly supports a role of T in mediating a life history trade-off between mating/competing and parenting, as well as signalling dominance to rivals and potential mates

Zeitreihenanalyse zu den Target-Forderungen der Deutschen Bundesbank und mögliche Zusammenhänge mit der expansiven Geldpolitik der EZB

Nicole Storp und Tobias Kordsmeyer, Universität Göttingen, beschäftigen sich mit der dynamischen Entwicklung von Target-Salden der Deutschen Bundesbank. Im Zeitraum vom 1. Januar 1999 bis 31. Dezember 2018 stellen die Autoren drei starke Anstiege in den Target-Forderungen der Deutschen Bundesbank fest. Ihre Analyse zeigt, dass vermutlich die Turbulenzen auf dem europäischen Interbankenmarkt den ersten Anstieg verursacht haben, während die zwei weiterfolgenden Steigerungen durch die expansive Geldpolitik der Europäischen Zentralbank mitbegründet wurden

Kordsmeyer.2021_capital-integrative-concept-human-characteristics-behaviour-reproductive-success-fitness

According to evolutionary theory, human cognition and behaviour are based on adaptations selected for their contribution to reproduction in the past, which in the present may result in differential reproductive success and inclusive fitness. Because this depiction is broad and human behaviour often separated from this ultimate outcome (e.g. increasing childlessness), evolutionary theory can only incompletely account for human everyday behaviour. Moreover, effects of most studied traits and characteristics on mating and reproductive success turned out not to be robust. In this article, an abstract descriptive level for evaluating human characteristics, behaviour, and outcomes is proposed, as a predictor of long-term reproductive success and fitness. Characteristics, behaviour, and outcomes are assessed in terms of attained and maintained capital, defined by more concrete (e.g. mating success, personality traits) and abstract (e.g. influence, received attention) facets, thus extending constructs like embodied capital and the social capital theory, which focusses on resources embedded in social relationships. Situations are framed as opportunities to gain capital, and situational factors function as elicitors for gaining and evaluating capital. Combined capital facets should more robustly predict reproductive success and (theoretically) fitness than individual fitness predictors. Different ways of defining and testing these associations are outlined, including a method for empirically examining the psychometric utility of introducing a capital concept. Further theorising and empirical research should more precisely define capital and its facets, and test associations with (correlates of) reproductive success and fitness

Preprint: Kordsmeyer & Penke, "The association of three indicators of developmental instability with mating success in humans"

Developmental instability (DI) has been proposed to relate negatively to aspects of evolutionary fitness, like mating success. One suggested indicator is fluctuating asymmetry (FA), random deviations from perfect symmetry in bilateral bodily traits. A meta-analytically robust negative association between FA and number of lifetime sexual partners has been previously shown in men and women. We examined the relationship between bodily FA across twelve traits and indicators of quantitative mating success in 284 individuals (141 males, age 19-30 years). Two further indicators of DI, minor physical anomalies (MPAs) and asymmetry in palmar atd angles, were also assessed. For men, no significant associations were detected, whereas for women, unexpected positive relationships of FA with the number of lifetime sexual partners and one-night stands emerged. Thus, in a large sample and using a more highly aggregated FA index, our study fails to replicate previous findings, though equivalence testing also did not support deviation from previous meta-analytic estimates, especially for men. No associations were found for MPAs and FA in atd angles in either sex