Decreasing body size has been proposed as a universal response to increasing temperatures. The physiology behind the response is well established for ectotherms inhabiting aquatic environments: as ...higher temperatures decrease the aerobic capacity, individuals with smaller body sizes have a reduced risk of oxygen deprivation. However, empirical evidence of this response at the scale of communities and ecosystems is lacking for marine fish species. Here, we show that over a 40‐year period six of eight commercial fish species in the North Sea examined underwent concomitant reductions in asymptotic body size with the synchronous component of the total variability coinciding with a 1–2 °C increase in water temperature. Smaller body sizes decreased the yield‐per‐recruit of these stocks by an average of 23%. Although it is not possible to ascribe these phenotypic changes unequivocally to temperature, four aspects support this interpretation: (i) the synchronous trend was detected across species varying in their life history and life style; (ii) the decrease coincided with the period of increasing temperature; (iii) the direction of the phenotypic change is consistent with physiological knowledge; and (iv) no cross‐species synchrony was detected in other species‐specific factors potentially impacting growth. Our findings support a recent model‐derived prediction that fish size will shrink in response to climate‐induced changes in temperature and oxygen. The smaller body sizes being projected for the future are already detectable in the North Sea.
Abstract
In Europe, uptake of electronic monitoring (EM) has been hindered by a lack of potential cost savings, given low existing observer coverage, and resistance from industry to greater ...enforcement of the landing obligation. To assess why certain vessels volunteer for EM and what their subsequent changes in behaviour tell us about those of the wider fleet over time, this study investigates effects of EM on discarding of North Sea cod by Scottish demersal trawlers. As discard data were limited, weight of small cod (grade 5) landed per trip was selected as an indicator of discarding and modelled to describe discard patterns from 2006 to 2016 encompassing the EM-verified cod quota management scheme (2010–2016). Findings show that EM leads to reduced instances of discarding of small cod by participants. However, evidence suggests non-participant vessels were driven to greater levels of discarding due to quota acquisition by participants. Vessels volunteering for EM trials were not predisposed towards greater compliance. Landings data do not support the trial objective of incentivising avoidance of small cod being met. The influence of participants on non-participants has implications for how vessels are selected, and management of behavioural adaptions required to ensure participants remain representative of the wider fleet.
In collectivist cultures, families tend to be characterized by respect for parental authority and strong, interdependent ties. Do these aspects of collectivism exert countervailing pressures on mate ...choices and relationship quality? In the present research, we found that collectivism was associated with greater acceptance of parental influence over mate choice, thereby driving relationship commitment down (Studies 1 and 2), but collectivism was also associated with stronger family ties (referred to as family allocentrism), which drove commitment up (Study 2). Along similar lines, Study 1 found that collectivists' greater acceptance of parental influence on mate choice contributed to their reduced relationship passion, whereas Study 2 found that their greater family allocentrism may have enhanced their passion. Study 2 also revealed that collectivists may have reported a smaller discrepancy between their own preferences for mates high in warmth and trustworthiness and their perception of their parents' preferences for these qualities because of their stronger family allocentrism. However, their higher tolerance of parental influence may have also contributed to a smaller discrepancy in their mate preferences versus their perceptions of their parents' preferences for qualities signifying status and resources. Implications for the roles of collectivism, parental influence, and family allocentrism in relationship quality and mate selection will be discussed.
Complex natural systems with eroded resilience, such as populations, ecosystems and socio‐ecological systems, respond to small perturbations with abrupt, discontinuous state shifts, or critical ...transitions. Theory of critical transitions suggests that such systems exhibit fold bifurcations featuring folded response curves, tipping points and alternate attractors. However, there is little empirical evidence of fold bifurcations occurring in actual complex natural systems impacted by multiple stressors. Moreover, resilience of complex systems to change currently lacks clear operational measures with generic application. Here, we provide empirical evidence for the occurrence of a fold bifurcation in an exploited fish population and introduce a generic measure of ecological resilience based on the observed fold bifurcation attributes. We analyse the multivariate development of Barents Sea cod (Gadus morhua), which is currently the world's largest cod stock, over six decades (1949–2009), and identify a population state shift in 1981. By plotting a multivariate population index against a multivariate stressor index, the shift mechanism was revealed suggesting that the observed population shift was a nonlinear response to the combined effects of overfishing and climate change. Annual resilience values were estimated based on the position of each year in relation to the fitted attractors and assumed tipping points of the fold bifurcation. By interpolating the annual resilience values, a folded stability landscape was fit, which was shaped as predicted by theory. The resilience assessment suggested that the population may be close to another tipping point. This study illustrates how a multivariate analysis, supported by theory of critical transitions and accompanied by a quantitative resilience assessment, can clarify shift mechanisms in data‐rich complex natural systems.
Social isolation during the COVID-19 pandemic increased negative affect and feelings of loneliness among university students.
Given that identifying as a member of a social group, like a university ...student, serves as a protective factor against diminished well-being, we examined whether students' social identity might offer a "social cure" during COVID-related remote learning.
Three hundred fifty-six students from a large, public university that was fully remote in 2021.
Students with a stronger social identity as a member of their university reported lower loneliness and greater positive affect balance during remote learning. Social identification was also associated with greater academic motivation, whereas two well-established predictors of positive student outcomes - perceived social support and academic performance - were not. Nonetheless, academic performance, but not social identification, predicted lower general stress and COVID-related worry.
Social identity may be a potential social cure for university students who are learning remotely.
The purpose of this research was to examine the associations of attachment anxiety and avoidance with personal growth following relationship dissolution, and to test breakup distress, rumination, and ...tendency to rebound with new partners as mediators of these associations. Study 1 (N = 411) and Study 2 (N = 465) measured attachment style, breakup distress, and personal growth; Study 2 additionally measured ruminative reflection, brooding, and proclivity to rebound with new partners. Structural equation modelling revealed in both studies that anxiety was indirectly associated with greater personal growth through heightened breakup distress, whereas avoidance was indirectly associated with lower personal growth through inhibited breakup distress. Study 2 further showed that the positive association of breakup distress with personal growth was accounted for by enhanced reflection and brooding, and that anxious individuals' greater personal growth was also explained by their proclivity to rebound. These findings suggest that anxious individuals' hyperactivated breakup distress may act as a catalyst for personal growth by promoting the cognitive processing of breakup-related thoughts and emotions, whereas avoidant individuals' deactivated distress may inhibit personal growth by suppressing this cognitive work.
Bicultural youths are at higher risk of mental health problems and are less likely to utilize mental health services, yet our knowledge of their mental health literacy and help-seeking behaviours ...remains limited.
To fill this gap, the current study explored bicultural youths' mental health literacy and stigma by conducting semi-structured interviews with 14 Canadian university students in 2021.
Our analysis revealed that bicultural youths may be torn between two worlds: intergenerational tensions between participants assimilated into individualistic Canadian culture and their more collectivist parents meant that they had different cultural perceptions of mental health literacy and stigma. While being caught between these two worlds may be detrimental for bicultural youth, our results also suggested that a trans-cultural factor-celebrities' mental health journeys-may promote help-seeking behaviour across participants. Furthermore, our study speaks to the ways that unprecedented events such as the COVID-19 pandemic impact mental health literacy among bicultural youth. Our findings might be used by university mental health services to encourage help-seeking among bicultural students.
The acculturation of mental health literacy, stigma, and associated intergenerational differences needs to be considered by university wellness services.
Many repatriates find it challenging to readjust to their heritage culture after spending a significant period of time abroad. Research on predictors of readjustment, however, remains limited. The ...present study in particular investigated the identification of third culture individuals (TCIs) - that is, individuals who spent their formative years outside of their heritage culture - with an abstract, third culture. Our findings demonstrated that TCIs' identification with the third culture was empirically distinct from that of the heritage and host cultures. The present study further examined whether several variables - sojourner type (TCI vs. non-TCI), perceived conflict between heritage and host culture, perceived cultural distance, and cultural identification with heritage and other cultures - predicted psychological readjustment (stress, anxiety, depression and overall psychological readjustment). The results showed that strong heritage culture identification was associated with better psychological readjustment, whereas cultural conflict was generally associated with poorer readjustment. Furthermore, sojourner type significantly moderated the latter association, such that cultural conflict predicted the stress aspect of psychological readjustment for non-TCIs, but not for TCIs. As the present investigation is the first study to empirically establish identification with a 'third culture' we discuss implications for the literature on third culture individuals and psychological adjustment upon re-entry.
Abstract
Fat content indicates individual condition and fuels annual reproductive cycles in many fish species. These cycles, coupled with ecosystem changes, can result in large intra- and ...inter-annual fluctuations in fat content. However, quantifying this variability is challenging when scientific sampling does not cover the full reproductive cycle. Scottish and Dutch fish processors routinely measure muscle fat content of North Sea autumn-spawning herring (Clupea harengus) throughout fishing seasons. We validated these high temporal resolution data by estimating a strong intra-annual signal in fat content, which matched herring reproductive status. Fat content increased from 4.5% 95% CI 0.03, 0.06 to 16.1% 95% CI 0.15, 0.17 during May and June before plateauing and decreasing to 9.1% 95% CI 0.08, 0.10 in September, which coincided with the onset of spawning. We also examined inter-annual variability in the seasonal pattern and the timing and magnitude of peak fat content from 2006 to 2020. Inter-annually, fat content differed from the mean pattern during the feeding or spawning periods in years 2013, 2015–2017, 2019, and 2020. There was no difference in the timing and magnitude of peak fat content between years. Our study validates the scientific use of routinely collected fat content data from pelagic fish processors.
Many families worldwide have at least one member with a behavioral or mental disorder, and yet the majority of the public fails to correctly recognize symptoms of mental illness. Previous research ...has found that Mental Health Literacy (MHL)-the knowledge and positive beliefs about mental disorders-tends to be higher in European and North American cultures, compared to Asian and African cultures. Nonetheless quantitative research examining the variables that explain this cultural difference remains limited. The purpose of our study was fourfold: (a) to validate measures of MHL cross-culturally, (b) to examine the MHL model quantitatively, (c) to investigate cultural differences in the MHL model, and (d) to examine collectivism as a predictor of MHL. We validated measures of MHL in European American and Indian samples. The results lend strong quantitative support to the MHL model. Recognition of symptoms of mental illness was a central variable: greater recognition predicted greater endorsement of social causes of mental illness and endorsement of professional help-seeking as well as lesser endorsement of lay help-seeking. The MHL model also showed an overwhelming cultural difference; namely, lay help-seeking beliefs played a central role in the Indian sample, and a negligible role in the European American sample. Further, collectivism was positively associated with causal beliefs of mental illness in the European American sample, and with lay help-seeking beliefs in the Indian sample. These findings demonstrate the importance of understanding cultural differences in beliefs about mental illness, particularly in relation to help-seeking beliefs.
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