In social species, conflict with outsiders is predicted to affect within-group interactions and thus influence group dynamics and the evolution and maintenance of sociality. Although empirical evidence exists for a relationship between out-group conflict and intragroup behavior in humans, experimental tests in other animals are rare. In a model fish system, we show that simulated out-group intrusions cause postconflict increases in intragroup affiliation but no changes in postconflict intragroup aggression. Postconflict affiliation was greater following intrusions by neighboring compared with nonneighboring individuals; neighbors represent greater threats to the dominance rank and breeding success of residents, and they are visible in the aftermath of the intrusion. By providing strong evidence of a link between out-group conflict and postconflict intragroup behavior and demonstrating that intragroup affiliation is affected by the nature of the out-group intrusion, our study shows the importance of considering postconflict behavior for our understanding of cooperation and social structure.
Subjective memory and objective memory performance have predictive utility for clinically relevant outcomes in older adults. Previous research supports certain overlap between objective performance and subjective ratings of memory. These studies are typically cross-sectional or use baseline data only to predict subsequent change. The current study uses a parallel process model to examine concurrent changes in objective memory and subjective memory. We combined data from two populationbased Swedish studies of individuals aged 80 + years, assessed every 2 years (OCTO-3 measurement occasions, OCTO-Twin-5 measurement occasions) yielding 607 participants (66% female). The results confirmed that both objective and subjective memory declined over time. The association between the slope of objective memory and subjective memory was statistically significant for women but not for men. This pattern remained after accounting for age and depressive symptoms. Our findings suggest that, in population-based samples of the oldest old, women seem to show better metacognitive abilities in detecting and reporting changes in memory. Memory changes for men may be better identified by objective performance as their self-assessment of memory changes is not associated with actual change in memory performance.
School engagement has been shown to be a strong predictor for school achievement. Previous studies have focused on the role of individual and contextual factors to explain school achievement, with few examining the role of siblings. This study used data of 451 adolescent sibling pairs from the Iowa Youth and Families Project to investigate the associations between school engagement and achievement in siblings by considering gender composition and birth order. Data were collected in families’ home and obtained for a target child in the 7th grade and for a sibling within 4 years of age. Average age of younger siblings (55% female) was 11.56 (SD = 1.27), while older siblings (49% female) had an average age of 13.92 (SD = 1.47). Using the two-member, four-group actor-partner interdependence model (APIM), results showed that older siblings’ engagement was positively related with younger siblings’ achievement in same-gender sibling pairs, but not in sibling pairs of opposite gender. Younger siblings’ engagement was independent of older siblings’ achievement regardless of siblings’ gender. Implications for parents and professionals suggest that support for older siblings could also benefit younger siblings in same gender pairs.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.