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Individuals occupying dominant and subordinate positions in social hierarchies exhibit divergent behaviours, physiology and neural functioning. Dominant animals express higher levels of dominance behaviours such as aggression, territorial defence and mate-guarding. Dominants also signal their status via auditory, visual or chemical cues. Moreover, dominant animals typically increase reproductive behaviours and show enhanced spatial and social cognition as well as elevated arousal. These biobehavioural changes increase energetic demands that are met via shifting both energy intake and metabolism and are supported by coordinated changes in physiological systems including the hypothalamic–pituitary–adrenal and hypothalamic–pituitary–gonadal axes as well as altered gene expression and sensitivity of neural circuits that regulate these behaviours. Conversely, subordinate animals inhibit dominance and often reproductive behaviours and exhibit physiological changes adapted to socially stressful contexts. Phenotypic changes in both dominant and subordinate individuals may be beneficial in the short-term but lead to long-term challenges to health. Further, rapid changes in social ranks occur as dominant animals socially ascend or descend and are associated with dynamic modulations in the brain and periphery. In this paper, we provide a broad overview of how behavioural and phenotypic changes associated with social dominance and subordination are expressed in neural and physiological plasticity. This article is part of the theme issue ‘The centennial of the pecking order: current state and future prospects for the study of dominance hierarchies’. [ABSTRACT FROM AUTHOR]

Across species, social hierarchies are often governed by dominance relations. In humans, where there are multiple culturally valued axes of distinction, social hierarchies can take a variety of forms and need not rest on dominance relations. Consequently, humans navigate multiple domains of status, i.e. relative standing. Importantly, while these hierarchies may be constructed from dyadic interactions, they are often more fundamentally guided by subjective peer evaluations and group perceptions. Researchers have typically focused on the distinct elements that shape individuals’ relative standing, with some emphasizing individual-level attributes and others outlining emergent macro-level structural outcomes. Here, we synthesize work across the social sciences to suggest that the dynamic interplay between individual-level and meso-level properties of the social networks in which individuals are embedded are crucial for understanding the diverse processes of status differentiation across groups. More specifically, we observe that humans not only navigate multiple social hierarchies at any given time but also simultaneously operate within multiple, overlapping social networks. There are important dynamic feedbacks between social hierarchies and the characteristics of social networks, as the types of social relationships, their structural properties, and the relative position of individuals within them both influence and are influenced by status differentiation. This article is part of the theme issue ‘The centennial of the pecking order: current state and future prospects for the study of dominance hierarchies’. [ABSTRACT FROM AUTHOR]

Over 50% of patients are resistant to current treatments for depression. With a lifetime prevalence of 20.6% among US adults, it is evident that the present understanding of major depressive disorder is limited, and current experimental methods are inadequate to decode the complex pathology of depression. This study used a novel animal model, Repeated Forced Social Defeat, to induce depressive-like symptoms in mice in order to add to the current literature on depression. The study sample comprised forty wild type male C57BL/6 inbred mice. The Tube Test was utilized to determine the established social rankings within each group of mice. This was followed by administration of the Tail Suspension Test and a second administration of the Tube Test. Repeated Forced Social Defeat was administered a week after the second round of Tube Test administration, followed by one last round of the Tail Suspension Test. Results indicate that the dominant mice did not display significantly greater immobility times than the subordinate mice in the Tail Suspension test prior to- and after administration of Repeated Forced Social Defeat. However, there was a non-significant trend towards the dominant mice displaying greater immobility times in comparison to the subordinate mice post social defeat. Evidently, while there were no significant differences, dominant mice seem to display less resilience following social defeat in comparison to subordinate mice. A possible explanation for a lack of significant differences is a small sample size and short period of administration. These findings demonstrate the potential of utilizing Repeated Forced Social Defeat as a means to induce depressive-like symptoms in mice, as well as the relevance of dominance hierarchies in predicting susceptibility to specific stressors. Further investigation of Repeated Forced Social Defeat is warranted.

Socially isolated individuals face elevated rates of illness and death. Conventional measures of social connectedness reflect an individual's perceived network and can be subject to bias and variation in reporting. In this study of a large human social network, we find that greater indegree, a sociocentric measure of friendship and familial ties identified by a subject's social connections rather than by the subject, predicts significantly lower concentrations of fibrinogen (a biomarker of inflammation and cardiac risk), after adjusting for demographics, education, medical history and known predictors of cardiac risk. The association between fibrinogen and social isolation, as measured by low indegree, is comparable to the effect of smoking, and greater than that of low education, a conventional measure of socioeconomic disadvantage. By contrast, outdegree, which reflects an individual's perceived connectedness, displays a significantly weaker association with fibrinogen concentrations.

Every human society includes social hierarchies—relationships between individuals and groups of unequal rankor status. Recent research has shown that even preverbalinfants represent hierarchical relationships, expecting largeragents and agents from larger groups to win dominancecontests. However, to successfully navigate social hierarchies,infants must also integrate information about social rank intotheir own behavior, such as when deciding which individualsto approach and which to avoid. Here we demonstrate that two-year-old children (ages 21-31 months) preferred noveldominant agents to subordinates. That is, by the age of 21months, toddlers not only use phylogenetically stable cues topredict the winner of dominance contests, they also like thedominant agents better. This finding suggests that youngchildren use their ability to infer relative rank to selectivelyapproach dominant individuals.

In many group living animal species, individuals use aggression to gain and maintain social dominance to secure access to ecological resources and potential mates. While social dominance has many fitness benefits, there are also potential costs associated with frequent agonistic interactions and status display. One potential cost of social dominance is oxidative stress, the imbalance of reactive oxygen species and antioxidant capacity. In the cichlid species Astatotilapia burtoni, dominant males are aggressive, hold a breeding territory, and have an activated reproductive system resulting in larger gonads. Subordinate males are submissive, school with females, and are nonreproductive. Females are submissive under natural conditions, but in a female‐only group, a dominance hierarchy will form with dominant females taking on male‐typical behaviours including aggression, territory defence, and increased androgen levels. However, in contrast to males, social dominance is not linked to increased activation of the reproductive system in females, allowing us to test whether social dominance alone exposes individuals to increased oxidative stress. We compared dominant and subordinate females in female‐only groups in five markers of oxidative stress. Dominant females did not have higher levels of oxidative damage compared to same‐sex subordinates. This result contrasted to the trend in males in which dominant males had higher oxidative damage than their subordinate counterparts. Our findings suggest that the oxidative cost of social dominance is limited and support the notion that previously reported associations between high rank and increased oxidative stress is most likely driven by increased investment in reproduction. [ABSTRACT FROM AUTHOR]

Over 50% of patients are resistant to current treatments for depression. With a lifetime prevalence of 20.6% among US adults, it is evident that the present understanding of major depressive disorder is limited, and current experimental methods are inadequate to decode the complex pathology of depression. This study used a novel animal model, Repeated Forced Social Defeat, to induce depressive-like symptoms in mice in order to add to the current literature on depression. The study sample comprised forty wild type male C57BL/6 inbred mice. The Tube Test was utilized to determine the established social rankings within each group of mice. This was followed by administration of the Tail Suspension Test and a second administration of the Tube Test. Repeated Forced Social Defeat was administered a week after the second round of Tube Test administration, followed by one last round of the Tail Suspension Test. Results indicate that the dominant mice did not display significantly greater immobility times than the subordinate mice in the Tail Suspension test prior to- and after administration of Repeated Forced Social Defeat. However, there was a non-significant trend towards the dominant mice displaying greater immobility times in comparison to the subordinate mice post social defeat. Evidently, while there were no significant differences, dominant mice seem to display less resilience following social defeat in comparison to subordinate mice. A possible explanation for a lack of significant differences is a small sample size and short period of administration. These findings demonstrate the potential of utilizing Repeated Forced Social Defeat as a means to induce depressive-like symptoms in mice, as well as the relevance of dominance hierarchies in predicting susceptibility to specific stressors. Further investigation of Repeated Forced Social Defeat is warranted. [ABSTRACT FROM AUTHOR]

• Dominant-submissive relations form the basis of animal social hierarchy. • Extreme manifestation of dominance and submissiveness crosstalk with behavioral deviations. • Social rank behavioral assessments in rodents are based on the following competition substrates: territory, food, and sex. • We discuss the contradictory opinions on dominance/submissiveness concept. • The heritable nature of social rank is reinforced through selective breeding models. Social interactions for many species of animals are critical for survival, wellbeing, and reproduction. Optimal navigation of a social system increases chances for survival and reproduction, therefore there is strong incentive to fit into social structures. Social animals rely heavily on dominant-submissive behaviors in establishment of stable social hierarchies. There is a link between extreme manifestation of dominance/submissiveness and behavioral deviations. To understand neural substrates affiliated with a specific hierarchical rank, there is a real need for reliable animal behavioral models. Different paradigms have been consolidated over time to study the neurobiology of social rank behavior in a standardized manner using rodent models to unravel the neural pathways and substrates involved in normal and abnormal intraspecific social interactions. This review summarizes and discusses the commonly used behavioral tests and new directions for the assessment of dominance in rodents. We discuss the hierarchy inheritable nature and other critical issues regarding hierarchical rank manifestation which may help in designing social-rank-related studies that serve as promising pre-clinical tools in behavioral psychiatry. [ABSTRACT FROM AUTHOR]

Copyright of Archaeologia Lituana is the property of Vilnius University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Day-fresh Great Cormorant pellets were collected at a huge single winter roost at Kreupel island in Lake IJsselmeer, The Netherlands. The roost is situated on a sandy island, 3 m above the water level and is regularly used by 1000–8000+ Cormorants. By examining pellets and thus reconstructing the previous day's meal of Cormorants gathering at the roost, we explored spatio-temporal differences in the diet of individual birds. We found that structural differences in pellets (size, colour and structure) are related to their content (fish species and fresh mass of a daily meal). Structurally larger and lighter coloured pellets contained larger and coarser fish and represented a higher total fish mass. Pellets of different size and structure were non-randomly distributed at the roost. Birds positioned centrally in the roost produced on average larger pellets than birds at the edges. Cormorants having few or no food remains in their pellets were more frequently recorded on the edge of the roost than in the centre and in particular, they were more likely to be located to the rear of the roost. The same was true for pellets showing a bloody signature which may be linked to either injury by sharp fin rays or to a parasite induced effect. Pellet data were corroborated by observations of differential distribution of faecal splashes of Cormorants, showing that individuals in the centre of the roost produced most guano. Clear diet differences existed within the roost between birds in the centre and elsewhere in the roost, whereas smaller differences existed between the front, edge and rear of the roost. Our data suggest a social hierarchy based on higher foraging success of birds returning earlier to the roost and settling in the centre, hereby forcing later arriving and less successful Cormorants towards the edge, rear and front position. We conclude that position at the roost is a reflection of previous foraging success, possibly caused by differences in dominance between Cormorants during the period of communal foraging. From a methodological point of view, our study demonstrates that, because of structural differences in pellets and spatial differences in occurrence, it is important to collect pellets randomly if one is to describe a proper diet sample by using pellets at any given site. Especially in marshlands and under trees and bush growth with a lot of litter, the likely collection of larger, more conspicuous pellets will cause a bias towards the larger fish species and sizes. Also sampling only at edge locations or specifically at the centre of a roost may give biased results, as this may result in an under- or overestimation in reconstructed fish uptake (e.g. fish size, mass, species) from the waterbody under study. [ABSTRACT FROM AUTHOR]

Numerous neuroimaging studies have investigated the neural mechanisms of two mutually independent yet closely related cognitive processes aiding humans to navigate complex societies: social hierarchy-related learning (SH-RL) and social hierarchy-related interaction (SH-RI). To integrate these heterogeneous results into a more fine-grained and reliable characterization of the neural basis of social hierarchy, we combined coordinate-based meta-analyses with connectivity and functional decoding analyses to understand the underlying neuropsychological mechanism of SH-RL and SH-RI. We identified the anterior insula and temporoparietal junction (dominance detection), medial prefrontal cortex (information updating and computation), and intraparietal sulcus region, amygdala, and hippocampus (social hierarchy representation) as consistent activated brain regions for SH-RL, but the striatum, amygdala, and hippocampus associated with reward processing for SH-RI. Our results provide an overview of the neural architecture of the neuropsychological processes underlying how we understand, and interact within, social hierarchy.

Background: Social stress is an important environmental risk factor for the development of psychiatric disorders, including depression and anxiety disorders. Social stress paradigms are commonly used in rats and mice to gain insight into the pathogenesis of these disorders. The social instability stress (SIS) paradigm entails frequent (up to several times a week) introduction of one or multiple unfamiliar same-sex home-cage partners. The subsequent recurring formation of a new social hierarchy results in chronic and unpredictable physical and social stress. Purpose: We compare and discuss the stress-related behavioral and physiological impact of SIS protocols in rat and mouse, and address limitations due to protocol variability. We further provide practical recommendations to optimize reproducibility of SIS protocols. Methods: We conducted a systematic review in accordance with the PRISMA statement in the following three databases: PubMed, Web of Science and Scopus. Our search strategy was not restricted to year of publication but was limited to articles in English that were published in peer-reviewed journals. Search terms included ''social* instab*” AND (''animal” OR ''rodent” OR ''rat*” OR ''mice” OR ''mouse”). Results: Thirty-three studies met our inclusion criteria. Fifteen articles used a SIS protocol in which the composition of two cage mates is altered daily for sixteen days (SIS16D). Eleven articles used a SIS protocol in which the composition of four cage mates is altered twice per week for 49 days (SIS49D). The remaining seven studies used SIS protocols that differed from these two protocols in experiment duration or cage mate quantity. Behavioral impact of SIS was primarily assessed by quantifying depressive-like, anxiety-like, social-, and cognitive behavior. Physiological impact of SIS was primarily assessed using metabolic parameters, hypothalamus-pituitary-adrenal axis activity, and the assessment of neurobiological parameters such as neuroplasticity and neurogenesis. Conclusion: Both shorter and longer SIS protocols induce a wide range of stress-related behavioral and physiological impairments that are relevant for the pathophysiology of depression and anxiety disorders. To date, SIS16D has only been reported in rats, whereas SIS49D has only been reported in mice. Given this species-specific application as well as variability in reported SIS protocols, additional studies should determine whether SIS effects are protocol duration- or species-specific. We address several issues, including a lack of consistency in the used SIS protocols, and suggest practical, concrete improvements in design and reporting of SIS protocols to increase standardization and reproducibility of this etiologically relevant preclinical model of social stress.

Dorper rams (n = 24) were evaluated during the sexual resting season to determine their social rank (SR), either high (HSR) or low (LSR), under intensive management conditions in northern Mexico (25° N). Aggressive behaviors were quantified during male-to-male interactions, and appetitive and consummatory sexual behaviors during male-to-female interactions. Morphometric, live weight (LW), and body condition score (BCS) were recorded. During the early reproductive season, male-to-female behaviors were newly itemized simultaneously by seminal quality and quantity sampling. Finally, the dependent variables of the hemogram components were also quantified. Neither LW (61.25 ± 2.4 kg) nor morphometric variables differed between SR groups. However, BCS (2.25 vs. 2.66 u), sexual behaviors (i.e., approaches: 59.6 vs. 21.73 n, mating with ejaculation: 77.7 vs. 42.86 %, latency to ejaculation: 16.6 vs. 143.07 s), ejaculate volume (0.57 vs. 0.23 mL), and hemogram components favored the HSR rams (p < 0.05). Moreover, in their first male-to-female interaction, >50% of the LSR rams failed to display any sexual activity. HSR rams displayed a greater number of threatening behaviors, managing to displace LSR rams when exposed to estrus ewes during the male sexual resting season; more sexual behaviors; and an increased seminal volume in a non-live weight-dependent fashion.

The multi-group composition of diverse societies is associated with conflict and general outgroup intolerance. The intergroup literature has thus been committed to searching for variables that accentuate and alleviate negative outgroup attitudes. This study, therefore, examined the relationship between an orientation towards social inequality and outgroup intolerance among a sample of participants drawn from a culturally diverse society. An aspect of spirituality, transcendence, was also examined for its role in improving tolerance for outgroups. The study participants were from a university environment characterized by diversity in ethnic affiliations. The study outcomes show that a bias for social inequality leads to more intolerance of outgroups. Furthermore, transcendence was associated with increased tolerance for outgroups. The implications of systemic social inequalities of most societies for continued negative outgroup attitudes were emphasized. The role of transcendence in appealing to the humaneness of individuals and encouraging openness to diversity was discussed. Suggestions for future research are also discussed. [ABSTRACT FROM AUTHOR]

Social hierarchy can simply be defined as a term involving the supremacy of specific parties over "others". Specifically, with the onset of industrialization, social hierarchy came to be exercised as a norm within societies. This type of hierarchy results from the factors like economy, ruling power, race, or gender that cannot be regarded as universal parameters but rather as socially constructed categories. As a result of the socially constructed dualities like "rich vs. poor", "strong vs. weak", "educated vs. uneducated", or "male vs. female" in societies, certain groups of individuals are placed in one end point of the spectrum as "otherized" or "o(u)t[h]ermost". Multi-ethnic feminism has arisen as resistance against these types of duality categories enforced by the patriarchy. This study aims at analyzing the multi-ethnic feminist signs in the literary text entitled The Color Purple by Alice Walker (1983). Following the analysis of the text from a multi-ethnic feminist perspective, its Turkish translation is evaluated based on Öztürk Kasar's (2021) "systematics of designification in translation" that consists of nine levels of designification showing degrees of meaning transformation on the original sign(s). A total of 37 contexts are analyzed based on three main themes in multi-ethnic feminism, namely gender-based oppression, race-based oppression, and social norms-based oppression. The results show that in cases of meaning transformation in the target text, the feminist signs are found to be rendered through more severe or less violent signs referring to the oppression on the "other". It is concluded through the discussion of meaning transformations in the target text that literary feminisms should be able to shape the skopos of literary translators in deciding whether to reproduce patriarchal values in another culture or not. [ABSTRACT FROM AUTHOR]

Social hierarchy governs the physiological and biochemical behaviors of animals. Intestinal radiation injuries are common complications connected with radiotherapy. However, it remains unclear whether social hierarchy impacts the development of radiation-induced intestinal toxicity. Dominant mice exhibited more serious intestinal toxicity following total abdominal irradiation compared with their subordinate counterparts, as judged by higher inflammatory status and lower epithelial integrity. Radiation-elicited changes in gut microbiota varied between dominant and subordinate mice, being more overt in mice of higher status. Deletion of gut microbes by using an antibiotic cocktail or restructuring of the gut microecology of dominant mice by using fecal microbiome from their subordinate companions erased the difference in radiogenic intestinal injuries. Lactobacillus murinus and Akkermansia muciniphila were both found to be potential probiotics for use against radiation toxicity in mouse models without social hierarchy. However, only Akkermansia muciniphila showed stable colonization in the digestive tracts of dominant mice, and significantly mitigated their intestinal radiation injuries. Our findings demonstrate that social hierarchy impacts the development of radiation-induced intestinal injuries, in a manner dependent on gut microbiota. The results also suggest that the gut microhabitats of hosts determine the colonization and efficacy of foreign probiotics. Thus, screening suitable microbial preparations based on the gut microecology of patients might be necessary in clinical application.

How does the human brain support reasoning about social relations (e.g., social status, friendships)? Converging theories suggest that navigating knowledge of social relations may co-opt neural circuitry with evolutionarily older functions (e.g., shifting attention in space). Here, we analyzed multivoxel response patterns of fMRI data to examine the neural mechanisms for shifting attention in knowledge of a social hierarchy. The “directions” in which participants mentally navigated social knowledge were encoded in multivoxel patterns in superior parietal cortex, which also encoded directions of attentional shifts in space. Exploratory analyses implicated additional regions of posterior parietal and occipital cortex in encoding analogous mental operations in space and social knowledge. However, cross-domain analyses suggested that attentional shifts in space and social knowledge are likely encoded in functionally independent response patterns. Additionally, cross-participant multivoxel pattern similarity analyses indicated that “directions'' of mental navigation in social knowledge are signaled consistently across participants and across different social hierarchies in a set of brain regions, including the right superior parietal lobule. Taken together, these results elucidate the neural basis of navigating abstract knowledge of social relations, and its connection to more basic mental operations.

Dogs’ remarkable success in living in a human-dominated world rests on a set of adaptations to cohabitation with humans. In this paper, I review the nature of these adaptations. They include changes in reproductive and foraging behavior from their ancestor species, wolves, which can be understood as adaptations to the change from hunting live prey to feeding on human food residues. Dogs also show several changes in social behavior which are more controversial and even somewhat paradoxical. Contrary to theories of canine domestication which view dogs as less aggressive and more cooperative than wolves, several studies show that dogs’ social interactions with conspecifics are more hierarchical and competitive than are wolves’. As scavengers rather than hunters, dogs do not need to cooperate with conspecifics the way that wolves do. But how then can we understand dogs’ willingness to cooperate with humans? I propose an integrated account of dogs’ social behavior that does not assume that dogs need to recognize the species-identity of the individuals with whom they interact. Because of the overlap in formal signals of dominance and submission between dog and human and people’s complete control over the resources dogs need, I propose that people occupy a status of “super-dominance” over dogs. This conception suggests several new lines of research which could shed light on the human-dog relationship to the benefit of both partners.

Social dominance hierarchies are a common adaptation to group living and exist across a broad range of the animal kingdom. Social dominance is known to rely on the prefrontal cortex (PFC), a brain region that shows a protracted developmental trajectory in mice. However, it is unknown to what extent the social dominance hierarchy is plastic across postnatal development and how it is regulated. Here we identified a sensitive period for experience-dependent social dominance plasticity in adolescent male mice, which is regulated by mechanisms that affect cortical plasticity. We show that social dominance hierarchies in male mice are already formed at weaning and are highly stable into adulthood. However, one experience of forced losing significantly reduces social dominance during the adolescent period but not in adulthood, suggesting adolescence as a sensitive period for experience-dependent social dominance plasticity. Notably, robust adolescent plasticity can be prolonged into adulthood by genetic deletion of Lynx1, a molecular brake that normally limits cortical plasticity through modulation of cortical nicotinic signaling. This plasticity is associated with increased activation of established nodes of the social dominance network including dorsal medial PFC and medial dorsal thalamus evidenced by increased c-Fos. Pharmacologically mediated elevation of cortical plasticity by valproic acid rapidly destabilizes the hierarchy of adult wildtype animals. These findings provide insight into mechanisms through which increased behavioral plasticity may be achieved to improve therapeutic recovery from psychiatric disorders that are associated with social deficits.

Dogs’ remarkable success in living in a human-dominated world rests on a set of adaptations to cohabitation with humans. In this paper, I review the nature of these adaptations. They include changes in reproductive and foraging behavior from their ancestor species, wolves, which can be understood as adaptations to the change from hunting live prey to feeding on human food residues. Dogs also show several changes in social behavior which are more controversial and even somewhat paradoxical. Contrary to theories of canine domestication which view dogs as less aggressive and more cooperative than wolves, several studies show that dogs’ social interactions with conspecifics are more hierarchical and competitive than are wolves’. As scavengers rather than hunters, dogs do not need to cooperate with conspecifics the way that wolves do. But how then can we understand dogs’ willingness to cooperate with humans? I propose an integrated account of dogs’ social behavior that does not assume that dogs need to recognize the species-identity of the individuals with whom they interact. Because of the overlap in formal signals of dominance and submission between dog and human and people’s complete control over the resources dogs need, I propose that people occupy a status of “super-dominance” over dogs. This conception suggests several new lines of research which could shed light on the human-dog relationship to the benefit of both partners. [ABSTRACT FROM AUTHOR]

Background: Public awareness is crucial for successful deployment of tidal energy, a renewable energy source that can provide clean electricity to remote islands. However, considering public attitudes on tidal energy are not well known, especially in developing countries, a barrier exists in implementing public engagement strategies. This study aims to contribute by identifying strategies for information provision—the initial step in public engagement—and estimate how these can be engaged to enhance support for tidal energy among the local public in a remote area of a developing country, in this case, Flores Timur Regency, Indonesia, considering their socio-cultural background. Methods: In this paper, we employ statistical analyses using multinomial probit modelling to identify the key variables that shape information flow. The aptness of the variables is then verified using post-estimation techniques for their use as input parameters for the simulation of the information flow in the field study area. Agent-based simulation (ABS) is employed to replicate the actual conditions in Flores Timur Regency, Indonesia, and simulate the flow of information through the local community. Results: According to the multinomial probit estimations, the people belonging to the top hierarchical group show a higher probability to support tidal energy compared to the members belonging to the lower groups. Understandably, around twice as many information flow cycles are needed to disseminate information to the members of the lowest hierarchical group, compared to the members of the top hierarchical group. The results also show that increasing the amount of available information has a positive impact on information dissemination. Conclusions: This study demonstrated that information provision is highly effective with propagation of information that specifically highlights the individual benefits, rather than the community benefits of tidal energy. Additionally, savings in terms of costs, time, and efforts can be realized if the most influential members of the local community are targeted initially before including all other stakeholders. The study also indicated that locals absorb more information and increase their support for tidal energy when additional data is made available. Finally, as long-term strategy, information provision becomes most effective when the local population gains higher educational capabilities. [ABSTRACT FROM AUTHOR]

This research incorporates Corpus Linguistic techniques with the socio-cognitive approach (SCA) to Critical Discourse Studies (CDS) to analyse the discursive representation of the British Monarchy (BM) through the categorisation of its individual members within the Now Corpus from 2010–2020. Analysis concentrated on their categorisation around key events over the ten-year period, most notably the accusations that Prince Andrew had sexual relations with a minor and Prince Harry's and Meghan Markle's decision to relinquish their roles within the Monarchy. Significantly, the Royals were positively represented through the affixation of agency and active form to attach them to positive actions, for instance, performing work and charity related duties. Negativity was deemphasised via the removal of agency, passive use and a refocus onto less serious acts which distanced them, particularly the Queen and Prince Andrew, from scandal. [ABSTRACT FROM AUTHOR]

Social hierarchy theory predicts that the power and status of an organizational function have a first-order effect on the function's ability to influence outcomes. We find that the rank of the title of the top tax executive is positively associated with tax planning after controlling for treatment effects. Our inferences remain when (1) using changes in the size of the c-suite as a shock to the relative power and status of the tax function, and (2) examining promotions and demotions in title rank. Point estimates suggest that tax function power and status are up to 2.6 times as important as tax planning resources, up to 4.0 times as important as tax function-specific expertise, and, more often than not, more important than manager fixed effects. Overall, results suggest that the power and status of the tax function is often what matters most in determining tax outcomes. JEL Classifications: H25; L22; M41. [ABSTRACT FROM AUTHOR]

This paper considers the position of the Chinese elite in both national and international contexts. I show that the Chinese elite has converged with the global elite in terms of their incomes, and that many senior Chinese executives are at least as well paid as their counterparts in rich countries. Their insertion into the global elite is further demonstrated by their increasing participation in the World Economic Forum. But this international convergence has been mirrored by national divergence: economic inequality has risen within China, extending the distance between elites and the rest of the population. I show that for top income groups, the relative cost of employing a median wage worker for their personal service has plummeted, increasing their entitlements over labor and thus their capacity to dominate their compatriots. This has been accompanied by a dramatic rise in the reliance of the elite on domestic workers, a traditional symbol of social inequality. Thus the convergence of Chinese elites with their international counterparts has gone hand in hand with both rising economic inequality and rising social inequality within China. [ABSTRACT FROM AUTHOR]

Social dominance hierarchies are a common adaptation to group living and exist across a broad range of the animal kingdom. Social dominance is known to rely on the prefrontal cortex (PFC), a brain region that shows a protracted developmental trajectory in mice. However, it is unknown to what extent the social dominance hierarchy is plastic across postnatal development and how it is regulated. Here we identified a sensitive period for experience-dependent social dominance plasticity in adolescent male mice, which is regulated by mechanisms that affect cortical plasticity. We show that social dominance hierarchies in male mice are already formed at weaning and are highly stable into adulthood. However, one experience of forced losing significantly reduces social dominance during the adolescent period but not in adulthood, suggesting adolescence as a sensitive period for experience-dependent social dominance plasticity. Notably, robust adolescent plasticity can be prolonged into adulthood by genetic deletion of Lynx1 , a molecular brake that normally limits cortical plasticity through modulation of cortical nicotinic signaling. This plasticity is associated with increased activation of established nodes of the social dominance network including dorsal medial PFC and medial dorsal thalamus evidenced by increased c-Fos. Pharmacologically mediated elevation of cortical plasticity by valproic acid rapidly destabilizes the hierarchy of adult wildtype animals. These findings provide insight into mechanisms through which increased behavioral plasticity may be achieved to improve therapeutic recovery from psychiatric disorders that are associated with social deficits. [ABSTRACT FROM AUTHOR]

Groups of social animals are often organized into dominance hierarchies that are formed through pairwise interactions. There is much experimental data on hierarchies, examining such things as winner, loser, and bystander effects, as well as the linearity and replicability of hierarchies, but there is a lack evolutionary analyses of these basic observations. Here I present a game theory model of hierarchy formation in which individuals adjust their aggressive behavior toward other group members through reinforcement learning. Individual traits such as the tendency to generalize learning between interactions with different individuals, the rate of learning, and the initial tendency to be aggressive are genetically determined and can be tuned by evolution. I find that evolution favors individuals with high social competence, making use of individual recognition, bystander observational learning, and, to a limited extent, generalizing learned behavior between opponents when adjusting their behavior toward other group members. The results are in qualitative agreement with experimental data, for instance, in finding weaker winner effects compared to loser effects. [ABSTRACT FROM AUTHOR]

When confined in pairs, juvenile rainbow trout (Oncorhynchus mykiss) form dominance hierarchies in which subordinate fish exhibit characteristic physiological changes including reduced growth rates and chronically elevated plasma cortisol concentrations. We hypothesized that alterations in protein metabolism contribute to the reduced growth rate of socially stressed trout, and predicted that subordinate trout would exhibit reduced rates of protein synthesis coupled with increases in protein degradation. Protein metabolism was assessed in dominant and subordinate fish after 4 days of social interaction, and in fish that were separated after 4 days of interaction for a 4 days recovery period, to determine whether effects on protein metabolism recovered when social stress was alleviated. Protein metabolism was assessed in liver and white muscle by measuring the fractional rate of protein synthesis and markers of protein degradation. In the white muscle of subordinate fish, protein synthesis was inhibited and activities of the ubiquitin-proteasome pathway (UPP) and the autophagy lysosomal system (ALS) were elevated. By contrast, the liver of subordinate fish exhibited increased rates of protein synthesis and activation of the ALS. When allowed to recover from chronic social stress for 4 days, differences in protein metabolism observed in white muscle of subordinate fish during the interaction period disappeared. In liver, protein synthesis returned to baseline levels during recovery from social stress, but markers of protein degradation did not. Collectively, these data support the hypothesis that inhibition of muscle protein synthesis coupled with increases in muscle protein breakdown contribute to the reduced growth rates of subordinate rainbow trout. [ABSTRACT FROM AUTHOR]

The main purpose of the present research was to examine the moderating effect of system-justifying beliefs on the relationship between a target's hierarchical position in an organizational context and perceived competence. Through three experiments we manipulated an employee's hierarchical position in various ways and examined the effects on social judgment. Participants' system-justifying beliefs were assessed in an ostensibly unrelated study. In Studies 1 and 2, as predicted, only participants high in system justification rated the highposition target as more competent than the low-position target. A very different pattern of results emerged when experimentally disentangling hierarchy based on status, and hierarchy based on power (Study 3). Individuals who are respected and admired by others (high-status individuals) were systematically valued on competence, whereas individuals who have asymmetric control over valued resources (high-power individuals) were derogated on competence by participants low in system justification. The present studies provide greater insight into how social judgment can function to maintain the existing social hierarchy, and offer novel empirical support to the widely accepted idea that status and power refer to theoretically different constructs. [ABSTRACT FROM AUTHOR]

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Sufficient access to clean drinking water is essential for the production and welfare of dairy cows. However, dairy farms vary greatly in how they provide water to cows. Electronic drinkers are now available to monitor cows' water intake on individual level and can be used to better define their water need. The objective of this study was to validate the detection of agonistic replacements when competing for water access with a new electronic drinker and to explore the ability of using these interactions to identify the social hierarchy within a group of cows. A group of 22 Holstein mid-lactating cows were housed in a free-stall barn equipped with 6 electronic drinkers, 22 individual feeders and 7 cameras. For 9 days over the 18 days of the trial, agonistic interactions were identified via video. We used an algorithm relying on visit start times of subsequent cows at the electronic drinkers to automatically detect agonistic replacements. We determined 4 social hierarchies using the normalized David's score (NormDS) based on 1) agonistic interactions video observed in areas outside the drinkers, 2) agonistic interactions video observed at the drinkers, 3) replacements at the drinkers obtained from video, and 4) replacements at the drinkers detected by the algorithm. We found a weak correlation between the hierarchy recorded outside the drinkers and the one based on agonistic interactions at the drinkers. The hierarchy based on agonistic interactions at the drinkers was strongly correlated with the one relying on video-based replacements but showed a weaker association with the hierarchy relying on replacements detected by the algorithm. To explore the influence of dominance on drinker use, we defined dominant (n = 6), mid-dominant (n = 6), mid-subordinate (n = 4) and subordinate (n = 6) cows according to NormDS quartiles in the video-based replacement hierarchy. Subordinate cows drank less than the other social groups at the peak consumption of the whole group at 1800 h but drank more than the most dominant cows 2 hours later. Subordinate cows preferentially used the most isolated drinker of the barn, furthest from the feeding area, and they drank less from drinkers in higher density areas. Detecting replacements at the drinker can be useful in studies aimed to analyze the effect of social groups on individual drinking behaviour. However, we suggest that for the automatic detection of replacements at the drinker, technology that allows for the recording of non-drinking visits is necessary. • Agonistic replacements at drinkers can be used to determine cow's social hierarchy. • Automatic detection of agnostic replacement by connected drinker is possible. • Recording non drinking visits is needed to characterize social hierarchy at drinkers. • Hierarchy based on replacements at drinkers reflects drinking behaviour variations. [ABSTRACT FROM AUTHOR]

• Novel traits for rabbit feeding behaviour and cage hierarchy rank were identified. • Resource distribution traits and feed priority reveal an animal's hierarchical status. • Efficient animals ate less often, consumed smaller meals, and spent less time eating. • Efficient animals appeared to be subordinate. • An individual could impact cage mate feed efficiency by limiting its access to feed. Due to the lack of a recording system for individual consumption of group-housed rabbits, published studies about feeding behaviour are based on information recorded at the group- and not at the individual level and periods covering only a few days or, in some cases, only part of a day. Such information could be used to inform rabbit management systems but cannot be used for genetic selection. We aimed to generate and use information from a novel automated feeder for group-housed rabbits to identify new phenotypes for individual animals that could be incorporated into breeding programs to improve feed efficiency and social behaviour under different feeding regimens. At 39 d of age, rabbits from 15 batches were placed in cages and fed ad libitum to become used to the electronic feeder. From 42 to 58–59 d, one group of 1 086 rabbits was fed ad libitum (AL), while another group of 1 134 rabbits was fed on a restricted feeding schedule (R) by limiting the feeding time to the period between 1800 and 0600 h of the following day. We implemented a reliable multivariate method to remove anomalous feeding behaviour records. We then defined novel traits for feeding behaviour that apply to both types of feeding regimes, and for social behaviour that indicates an animal's rank within the cage hierarchy. We based these traits on feeder records and a biologically sound definition of a meal. Finally, we estimated the phenotypic correlations of those traits with growth and feed efficiency traits. Our findings demonstrate that variables about resource distribution among cage mates and an animal's priority for feed access were found to be good indicators of an animal's dominant or subordinate status within the cage. Based on results obtained in R animals (results were similar in AL animals), the most efficient animals were those that ate less frequently (phenotypic correlation with feed conversion ratio, rho = 0.6), and consumed smaller amounts per meal (rho = 0.7), spent less time at the feeder (rho = 0.4), and appeared to be subordinate, as they did not have priority access to the feeder (rho = −0.3), and had the smallest share of resources (range of rho = 0.2–0.6). We conclude that quantifying feeding and social behaviour traits can enhance the understanding of the mechanisms through which individuals exert their effects on the performance of their cage mates. [ABSTRACT FROM AUTHOR]

Social animals compete for limited resources, resulting in a social hierarchy. Although different neuronal subpopulations in the medial prefrontal cortex (mPFC), which has been mechanistically implicated in social dominance behavior, encode distinct social competition behaviors, their identities and associated molecular underpinnings have not yet been identified. In this study, we found that mPFC neurons projecting to the nucleus accumbens (mPFC-NAc) encode social winning behavior, whereas mPFC neurons projecting to the ventral tegmental area (mPFC-VTA) encode social losing behavior. High-throughput single-cell transcriptomic analysis and projection-specific genetic manipulation revealed that the expression level of POU domain, class 3, transcription factor 1 (Pou3f1) in mPFC-VTA neurons controls social hierarchy. Optogenetic activation of mPFC-VTA neurons increases Pou3f1 expression and lowers social rank. Together, these data demonstrate that discrete activity and gene expression in separate mPFC projections oppositely orchestrate social competition and hierarchy. [Display omitted] • Distinct mPFC neural populations oppositely regulate social competition behaviors • mPFC-NAc projection drives social winning • mPFC-VTA projection drives social losing • Pou3f1 expression level in mPFC-VTA neurons control social hierarchy Choi et al. find that distinct neuronal populations in the medial prefrontal cortex (mPFC) oppositely drive social hierarchy: mPFC neurons projecting to the nucleus accumbens (mPFC-NAc) for winning and those projecting to the ventral tegmental area (mPFC-VTA) for losing. Pou3f1 expression level in mPFC-VTA neurons regulates social hierarchy. [ABSTRACT FROM AUTHOR]

Social dominance is a universal phenomenon among grouped animals that profoundly affects survival, health, and reproductive success by determining access to resources, and exerting a powerful influence on subsequent behavior. However, the understanding of pain and anxiety comorbidities in dominant or subordinate animals suffering from chronic pain is not well-defined. Here, we provide evidence that subordinate mice are more susceptible to pain-induced anxiety compared to dominant mice. We propose that the gut microbiota may play a mediating role in this mechanism. Our findings demonstrate that transplantation of fecal microbiota from subordinate mice with chronic inflammatory pain, but not dominant mice, into antibiotics-treated pseudo-germ-free mice significantly amplifies anxiety-like phenotypes, highlighting the critical involvement of gut microbiota in this behavioral response. Using chronic inflammatory pain model, we carried out 16S rRNA sequencing and untargeted metabolomic analyses to explore the relationship between microbiota and metabolites in a stable social hierarchy of mice. Interestingly, anxiety-like behaviors were directly associated with some microbial genera and metabolites, especially bile acid metabolism. Overall, we have demonstrated a close relationship between social status and anxiety susceptibility, highlighting the contributions of gut microbiota and the associated metabolites in the high-anxiety state of subordinate mice with chronic inflammatory pain. • Social hierarchy modulates pain and anxiety comorbidity. • Subordinate mice are more susceptible to pain-induced anxiety-like behavior. • Gut microbiota and metabolites relate to anxiety in subordinate mice with chronic pain. [ABSTRACT FROM AUTHOR]

Resources are distributed unequally depending on the social status (SS) of people. Researchers have often used experiments to explain the role of SS in economic decisions. However, the diverse ways of inducing SS has produced contradictory results. The aim of this study was to analyze the effect of SS on the distribution of monetary resources in students aged 18 to 25 years from Córdoba (Argentina). Three experiments using mixed factorial designs were conducted. Different ways of inducing SS and the effect on decisions in different games were examined. In Experiment 1, the effect of two SS induction techniques on the decisions of the Ultimatum Game (UG) and Dictator Game (DG) was compared. In Experiment 2, the effect of SS on the same games, including Social Value Orientation (SVO) and Subjective Social Status (SSS) as covariates was analyzed. In Experiment 3, the role of SS, SVO and SSS in the DG and the Dictator Game Taking (DGT) was examined. In the three experiments, it was not found that SS had any effect on the decisions of the games. However, more rejection and negative valence was observed (Exp. 1: p < .001, n2 p =.72; Exp. 2: p < .001, n2 p = .65) for unfair offers than for fair ones (Exp. 2: p < .001). Also, pro-social individuals made fairer offers in the DG (Exp. 2: p < .05) and participants offered more money in the DGT than in the DG (Exp. 3: p = .01). Those findings showed that the effect of SS on behavioral responses is not robust, which highlights the need to obtain new experimental evidence to investigate its role in those decisions

Ethnic groups involved in separatist movements have often been engaged in violence, rather than electoral politics, in order to fulfil their demands. The present paper analyses the dynamics of the sovereignty movements of the Koch-Rajbanshi community of north-eastern India, an indigenous group that has used active and suppressed violence for accomplishing their demands along with electoral contests. Nuanced analyses of literature, electoral information, schedule-based surveys and personal interviews of Koch-Rajbanshi respondents were used for this purpose. Results indicated that most elected Koch-Rajbanshi representatives belonged to mainstream political parties and failed to bring about practical solutions for the sovereignty issue. The pro-sovereignty outfits were unable to gain electoral success and further hindered the movement. Fear of backlash from the ruling party also stopped many Koch-Rajbanshi commons from being involved in the electoral process. Accordingly, adequate electoral representation of Koch-Rajbanshi political groups was identified as the only democratic solution to this escalating conflict.

Hallyu fans are people who are dedicated to popular culture in South Korea, including music, drama and film. This study focuses on fans of Korean pop music, which is known as K-pop. Developments in digital communication technology have given rise to media such as forums, websites, video channels, and fan sites that are consumed by K-pop fans. Fans participate in multiple fandoms because these websites are easily accessed by public audiences. However, problems arise when fans start to compete, using their knowledge to help validate their existence and to help the perception of authentic identities within fan communities. This paper is based on virtual ethnographic fieldwork that identified fans’ constructions of their own identities and the building of a social hierarchy through various online practices. The research findings are based on four months of fieldwork with two online Hallyu fandoms; ELF (Ever Lasting Friends) and A.R.M.Y (Adorable Representative M.C. for Youth). The findings reveal that conflicts exist in certain fandoms which aid in defining fan identities and, at the same time, fans undertake positive socialising actions which contribute to the fandom itself. Interactions between fandoms also need to be recognised, since online fandoms can be seen as borderless.

Grey wolf optimizer (GWO) is an efficient swarm intelligence algorithm for kinds of optimization problems. However, GWO tends to be trapped in local optimum when solving large-scale problems. Social hierarchy is one of the main characteristics of GWO which affect the searching efficiency. Thus, an improved algorithm called hierarchy strengthened GWO (HSGWO) is proposed in this paper. First, the pack of wolves is roughly divided into two categories: dominant wolves and omega wolves. Second, the enhanced elite learning strategy is performed for dominant wolves to prevent the misguidance of low-ranking wolves and improve the collective efficiency. Then, the hybrid GWO and differential evolution (DE) strategy is executed for omega wolves to avoid falling into local optimum. In addition, a new hybrid one-dimensional and total-dimensional selection strategy is designed for omega wolves to balance the exploration and the exploitation during optimization. Finally, a perturbed operator is used to maintain the diversity of the population and further improve the exploration. To make a complete evaluation, the proposed HSGWO is first compared with six representative GWO variants for 50-dimensional problems based on CEC2014 benchmarks. The scalability of HSGWO is further tested by comparing it with eight state-of-the-art non-GWO algorithms for large-scale optimization problems with 100 decision variables. In addition, feature selection problem is used for testing the effectiveness of HSGWO on real-world applications. The experimental results demonstrated that the proposed algorithm outperforms other algorithms in terms of solution quality and convergence rate in most of the experiments.

With international demand for production systems aimed at thermal comfort and animal welfare, milk producers have become increasingly interested in compost barns. However, doubts about the behavioral aspects of cows in tropical and subtropical climates remain, because the compost barn system offers a larger bed area per animal at a lower stocking rate. The objective of this study was to evaluate whether the diurnal behaviors, hygiene and lameness of crossbred dairy cows are influenced by different number of lactations when housed in a compost-bedded pack barn system under hot and humid conditions. Crossbred cows (Holstein and Jersey), which were divided into two treatments based on number of lactations (primiparous and multiparous cows), were evaluated during lactation (n=12). The study was conducted from September 2015 to February 2016 in a compost barn in the southwest region of the state of Paraná, Brazil. Daytime behavior was observed between milking schedules using focal observations with 0/1 sampling. Cow hygiene and lameness were evaluated using subjective scores ranging from 1 to 4 and 1 to 5, respectively. Animal behavior and welfare was analyzed using Bayesian inference with a mixed effects model. The probabilities of dyspnea and pushing behaviors were higher (P

In intensive feeding systems, competition may be high and social dominance may affect animal performance by changing dry matter intake (DMI) and behavioral time budgets. If competition level is maintain over time, the strategies developed by heifers of different social status are expected to differ. Thus, the aim of this study was to compare individual DMI, intake rate and eating, ruminating, lying and standing behaviors in dominant (DOM) and subordinate (SUB) pre-pubertal dairy heifers in a model study implying continuous competitive situations. A total of 16 Holstein and Jersey×Holstein pre-pubertal heifers (251±10 days old, weighing 208±14 kg; mean±SEM) were allocated into eight homogeneous dyads. Each dyad was maintained during 120 days (day 0=beginning of measurements) in pens, and received a total mixed ration from one feeder/dyad. The DOM and SUB heifers was determined (day 0, twice during the first month of the experiment and every month afterwards) by observation of the winner in agonistic interactions in each dyad after the feed was supplied. The general activity pattern (eating, ruminating, lying and standing) of each heifer was recorded by direct instantaneous scan-sampling, every 10 min for 12 h, in 7 days (days 1, 21, 35, 60, 75, 100 and 120). Individual DMI was estimated with the double marker technique, in three intervals (I=days 17-26; II=days 78-87 and III=days 112-120), while estimated intake rate (kg/min) was calculated for each interval as the DMI per total eating time. After the experiment was concluded, data of the first 5 and the last 6 h of the 12 h scan-sampling (related to the moment the feed was supplied) was grouped according to the moments of greater and lesser competition for feed on each day. During the first 5 h, where competition was expected to be highest, no differences in eating behavior were found between heifers of different social status, but DOM heifers spent more time ruminating and lying than SUB heifers, while SUB spent more time standing than DOM heifers. No differences were found on DMI between DOM and SUB, but SUB ate at a faster rate on interval II compared with DOM heifers. In conclusion, in this model study of heifer dyads, SUB heifers had greater intake rate with no differences in feed intake, spent less time ruminating and lying, and more time standing than DOM heifers during the first hours after feed delivery.

The article focuses on hierarchical and inverse relations in social systems. Hierarchy is the basic form of organization in social systems. Complex hierarchies have the ability to form inverse relationships. Inverse relationships occur when the lower element in social hierarchy becomes the dominant, but formally remains in a subordinate position. In a hierarchical system, there are certain organizational principles that determine the mutual position of the elements. There are several such principles in complex hierarchies. Inversions arise when two or more organizational principles collide in social hierarchy. The developed inversions are a manifestation of internal contradictions in the hierarchical system. The accumulation of these contradictions can lead to the collapse of the hierarchical system. For example, the development of social inversions can cause a revolution in which certain organizational principles in the social system are abolished. But in some cases, resolving of these contradictions leads to another step in the progressive development of the system. Thus, the resolution of contradictions occurs when the subject actually moves to a higher position in the social hierarchy. One of the most important organizational principles that determine the position of the subject in the social hierarchy is based on the educational level of this subject. Increasing the level of education entails the increase of the subject’s social status. However, the position of the subject in the social hierarchy is also determined by other organizational principles. These principles may conflict with the educational organizational principle. As a result, there is a social inversion. Education is a factor that can both generate inversions in the social hierarchy and eliminate them. The development of society is closely connected with the manifestations of the educational organizational principle, with its interaction with other organizational principles in the social hierarchy. The analysis of inverse relations in social hierarchies is an effective research tool that allows to predict and prevent social tension in society.

Competition for resources shapes ecological and evolutionary relationships. Physiological capacities such as in locomotor performance can influence the fitness of individuals by increasing competitive success. Social hierarchy too can affect outcomes of competition by altering locomotor behaviour or because higher ranking individuals monopolize resources. Here, we tested the hypotheses that competitive success is determined by sprint performance or by social status. We show that sprint performance of individuals measured during escape responses (fast start) or in an accelerated sprint test did not correlate with realized sprint speed while competing for food within a social group of five fish; fast start and accelerated sprint speed were higher than realized speed. Social status within the group was the best predictor of competitive success, followed by realized speed. Social hierarchies in zebrafish are established within 7 days of their first encounter, and interestingly, there was a positive correlation between social status and realized speed 1 and 4 days after fish were placed in a group, but not after 7 days. These data indicate that physiological performance decreases in importance as social relationships are established. Also, maximal physiological capacities were not important for competitive success, but swimming speed changed with social context.