A Cascade Model of Sociodevelopmental Events Leading to Men's Perpetration of Violence Against Female Romantic Partners

Conceptually driven by life history theory, the current study investigated a hypothesized hierarchy of behaviors leading to men's perpetration of violence in intimate relationships. Using a series of hierarchical regressions, we tested a causal cascade model on data provided by 114 men in a committed romantic relationship. The results supported the hypothesized hierarchy of sociodevelopmental events: (1) men's childhood experiences with their parents’ parental effort predicted men's life history strategies; (2) men's life history strategies predicted men's behavioral self-regulation; (3) men's self-regulation predicted men's perceptions of partner infidelity risk; (4) perceptions of infidelity risk predicted men's frequency of engagement in nonviolent mate retention behaviors; (5) men's mate retention behaviors predicted men's frequency of partner-directed violence. The overall cascade model explained 36% of variance in men's partner-directed violence.

Tri-axial accelerometry shows differences in energy expenditure and parental effort throughout the breeding season in long-lived raptors

Cutting-edge technologies are extremely useful to develop new workflows in studying ecological data, particularly to understand animal behaviour and movement trajectories at the individual level. Although parental care is a well-studied phenomenon, most studies have been focused on direct observational or video recording data, as well as experimental manipulation. Therefore, what happens out of our sight still remains unknown. Using high-frequency GPS/GSM dataloggers and tri-axial accelerometers we monitored 25 Bonelli’s eagles (Aquila fasciata) during the breeding season to understand parental activities from a broader perspective. We used recursive data, measured as number of visits and residence time, to reveal nest attendance patterns of biparental care with role specialization between sexes. Accelerometry data interpreted as the Overall Dynamic Body Acceleration, a proxy of energy expenditure, showed strong differences in parental effort throughout the breeding season and between sexes. Thereby, males increased substantially their energetic requirements, due to the increased workload, while females spent most of the time on the nest. Furthermore, during critical phases of the breeding season, a low percentage of suitable hunting spots in eagles’ territories led them to increase their ranging behaviour in order to find food, with important consequences in energy consumption and mortality risk. Our results highlight the crucial role of males in raptor species exhibiting biparental care. Finally, we exemplify how biologging technologies are an adequate and objective method to study parental care in raptors as well as to get deeper insight into breeding ecology of birds in general.

Parental Effort and Outcome Goals_Preprint

In many East Asian societies, both Confucian emphasis on effortful learning and the instrumental value of academic grades for attaining social privilege have greatly impacted people’s achievement goals. In this study, we examined whether perceived parental effort goals and outcome goals would function independently from the often noted mastery and performance goals in prior Western literature in explaining East Asian college students’ academic dedication and self-handicapping. The reliability and the construct, concurrent, and incremental validity of newly developed scales for perceived parental effort goals and outcome goals were tested using two samples of Taiwanese students (Ns = 252, 269; 47.6% and 61.7% female; mean age = 20.44, 19.33 years). Results of confirmatory factor analyses supported the four-factor model of effort, outcome, mastery, and performance goals being distinct goal constructs. Hierarchical regression for examining the incremental validity of effort goals and outcome goals indicated that, above and beyond the influence of perceived parental mastery and performance goals, perceived parental effort goals predicted greater self-handicapping behaviors. The inverse effect of perceived parental effort goals in predicting academic adjustment may be explained by students’ sense of academic helplessness, which can be cultivated by prolonged exposure to such parental goals. The regression analyses also found perceived paternal, but not maternal, outcome goals predicted stronger academic dedication, suggesting that East Asian students may interpret paternal interest in test scores as concern for children’s future social and economic wellbeing and perceive similar maternal interest with apprehension.

Co-evolution of Traits

Often traits interact, so that considering the evolution of each in isolation gives too limited an account. As is demonstrated in this chapter, it is then crucial to allow for the co-evolution of traits when analysing evolutionary stability. In particular this is important when there there is disruptive selection. Criteria for stability are presented and are applied to a variety of systems. It is shown that role asymmetries can lead to different predictions compared with the analogous situation with the same payoffs but without such asymmetries. Disruptive selection can lead to the evolution of anisogamy. When parental ability and parental effort co-evolve, disruptive selection can lead to one sex evolving to be better at care and doing most of the care. Furthermore, disruptive selection can lead to multiple ESSs, as when prosocial behaviour and the propensity to disperse from the natal site co-evolve. As is shown, disruptive forces can also act when there is learning, leading to specialization. This chapter sets the scene for the chapter that follows, where the level of cooperation shown by individuals co-evolves with choosiness and social sensitivity.

Does offspring demand affect parental life-history trade-offs?

Life-history trade-offs between the number and size of offspring produced, and the costs of reproduction on future reproduction and survival can all be affected by different levels of parental effort. Because of these trade-offs the parents and the offspring have different optima for the amount of care given to the current brood, which leads to a conflict between parents and offspring. The offspring, as well as the parents, have the ability to affect parental effort, and thus changes in offspring traits have the potential to cause reproductive costs on the parents. Here, we used a repeated cross-fostering design to manipulate offspring demand during juvenile development in the burying beetle Nicrophorus vespilloides to examine whether responding to offspring begging incurs reproductive costs to the parent. After a manipulated first reproductive event, we gave each experimental female, that had been exposed to different levels of offspring demand, a chance to breed again, and monitored their survival. We found that larval demand influences the trade-off between the size and number of offspring produced, but has no impact on the reproductive costs through future reproduction or survival of the parent. The parents do, however, pay an overall fecundity cost for the general success of their first broods, but this cost was not related to the changes in the levels of larval begging. Other traits, including survival showed no costs of reproduction. Survival and the number of larvae successfully raised in the second broods correlated positively, indicating differences in the individual quality of the parents.