On the possibility of engineering social evolution in microfluidic environments.

Many species of microbes cooperate by producing public goods from which they collectively benefit. However, these populations are under the risk of being taken over by cheating mutants that do not contribute to the pool of public goods. Here we present theoretical findings that address how the social evolution of microbes can be manipulated by external perturbations to inhibit or promote the fixation of cheaters. To control social evolution, we determine the effects of fluid-dynamical properties such as flow rate or domain geometry. We also study the social evolutionary consequences of introducing beneficial or harmful chemicals at steady state and in a time-dependent fashion. We show that by modulating the flow rate and by applying pulsed chemical signals, we can modulate the spatial structure and dynamics of the population in a way that can select for more or less cooperative microbial populations.

Reduced social function in experimentally evolved Dictyostelium discoideum implies selection for social conflict in nature.

Many microbes interact with one another, but the difficulty of directly observing these interactions in nature makes interpreting their adaptive value complicated. The social amoeba Dictyostelium discoideum forms aggregates wherein some cells are sacrificed for the benefit of others. Within chimaeric aggregates containing multiple unrelated lineages, cheaters can gain an advantage by undercontributing, but the extent to which wild D. discoideum has adapted to cheat is not fully clear. In this study, we experimentally evolved D. discoideum in an environment where there were no selective pressures to cheat or resist cheating in chimaeras. Dictyostelium discoideum lines grown in this environment evolved reduced competitiveness within chimaeric aggregates and reduced ability to migrate during the slug stage. By contrast, we did not observe a reduction in cell number, a trait for which selection was not relaxed. The observed loss of traits that our laboratory conditions had made irrelevant suggests that these traits were adaptations driven and maintained by selective pressures D. discoideum faces in its natural environment. Our results suggest that D. discoideum faces social conflict in nature, and illustrate a general approach that could be applied to searching for social or non-social adaptations in other microbes.

Kin selection of time travel: the social evolutionary causes and consequences of dormancy.

A basic mechanism of kin selection is limited dispersal, whereby individuals remain close to their place of origin such that even indiscriminate social interaction tends to modify the fitness of genealogical kin. Accordingly, the causes and consequences of dispersal have received an enormous amount of attention in the social evolution literature. This work has focused on dispersal of individuals in space, yet similar logic should apply to dispersal of individuals in time (e.g. dormancy). We investigate how kin selection drives the evolution of dormancy and how dormancy modulates the evolution of altruism. We recover dormancy analogues of key results that have previously been given for dispersal, showing that: (1) kin selection favours dormancy as a means of relaxing competition between relatives; (2) when individuals may adjust their dormancy behaviour to local density, they are favoured to do so, resulting in greater dormancy in high-density neighbourhoods and a concomitant 'constant non-dormant principle'; (3) when dormancy is constrained to be independent of density, there is no relationship between the rate of dormancy and the evolutionary potential for altruism; and (4) when dormancy is able to evolve in a density-dependent manner, a greater potential for altruism is expected in populations with lower dormancy.

Adaptations to a cold climate promoted social evolution in Asian colobine primates.

The biological mechanisms that underpin primate social evolution remain poorly understood. Asian colobines display a range of social organizations, which makes them good models for investigating social evolution. By integrating ecological, geological, fossil, behavioral, and genomic analyses, we found that colobine primates that inhabit colder environments tend to live in larger, more complex groups. Specifically, glacial periods during the past 6 million years promoted the selection of genes involved in cold-related energy metabolism and neurohormonal regulation. More-efficient dopamine and oxytocin pathways developed in odd-nosed monkeys, which may have favored the prolongation of maternal care and lactation, increasing infant survival in cold environments. These adaptive changes appear to have strengthened interindividual affiliation, increased male-male tolerance, and facilitated the stepwise aggregation from independent one-male groups to large multilevel societies.

Selective selfishness in alarm calling behaviour by some members of wintering mixed-species groups of crested tits and willow tits.

Animals adjust their use of alarm calls depending on social environments. We tested whether dominant (adult) and subordinate (juvenile non-kin) male crested tits (Lophophanes cristatus) warn each other and heterospecific willow tits (Poecile montanus) across the wintering season. Birds rarely alarm called when feeding alone. Both adult and juvenile crested tits warned each other in early winter, and adults did so in the middle of wintering season. However, juvenile males rarely warned conspecific adult males in the middle of the winter. Both adult and juvenile males stopped giving alarm calls when feeding together at the end of wintering season. The results suggest that the mid-winter reduction of juvenile alarms could increase the likelihood of successful predator attacks on adults, increasing the chances for juveniles to replace adults and acquire their territories. By contrast, both adult and juvenile males produced alarm calls throughout the season when foraging together with willow tits. Whether juvenile male crested tits could be selectively altering alarm call propensity to endanger adult males, thereby selfishly enhancing their own succession to territory ownership, is discussed. The results add to the understanding of the origin of mixed-species groups and explain the dynamics of social communication. This article is part of the theme issue 'Mixed-species groups and aggregations: shaping ecological and behavioural patterns and processes'.

Social evolution as moral truth tracking in natural law.

Morality can be adaptive or maladaptive. From this fact come polarizing disputes on the meta-ethical status of moral adaptation. The realist tracking account of morality claims that it is possible to track objective moral truths and that these truths correspond to moral rules that are adaptive. In contrast, evolutionary anti-realism rejects the existence of moral objectivity and thus asserts that adaptive moral rules cannot represent objective moral truths, since those truths do not exist. This article develops a novel evolutionary view of natural law to defend the realist tracking account. It argues that we can identify objective moral truths through cultural group selection and that adaptive moral rules are likely to reflect such truths.

The social evolution of individual differences: Future directions for a comparative science of personality in social behavior.

Personality is essential for understanding the evolution of cooperation and conflict in behavior. However, personality science remains disconnected from the field of social evolution, limiting our ability to explain how personality and plasticity shape phenotypic adaptation in social behavior. Researchers also lack an integrative framework for comparing personality in the contextualized and multifaceted behaviors central to social interactions among humans and other animals. Here we address these challenges by developing a social evolutionary approach to personality, synthesizing theory, methods, and organizing questions in the study of individuality and sociality in behavior. We critically review current measurement practices and introduce social reaction norm models for comparative research on the evolution of personality in social environments. These models demonstrate that social plasticity affects the heritable variance of personality, and that individual differences in social plasticity can further modify the rate and direction of adaptive social evolution. Future empirical studies of frequency- and density-dependent social selection on personality are crucial for further developing this framework and testing adaptive theory of social niche specialization.

(In)tolerância como política: os discursos de direita e de esquerda no facebook / (In)tolerance as policy: the rightist and leftist discourses on facebook / (In)tolerancia como política: los discursos de la derecha y la izquierda en facebook

Este estudo tem como objetivo analisar traços da mentalidade potencialmente autoritária a partir do discurso de usuários do Facebook vinculados a páginas de cunho político autodeclarado de direita e de esquerda no Brasil. A Netnografia é utilizada como aporte metodológico para imersão on-line nas páginas "Eu era Direita e não sabia" e "Jovens de Esquerda", selecionadas por meio do Facebook Audience Insights, ferramenta disponibilizada pelo Facebook. Delas, foram extraídas oito postagens com maior engajamento (número de comentários, curtidas e compartilhamentos), identificadas pelo Netvizz. Foram coletados 3.489 comentários, os quais foram organizados em um corpus textual submetido ao software IRAMUTEQ e analisados sob a perspectiva da análise crítica imanente da teoria crítica. Como resultado, apresenta-se a forma como o pensamento autoritário se manifesta na racionalização da sociedade contemporânea e nas práticas discursivas em redes sociais on-line, enraizada no âmbito sociopolítico brasileiro, ameaçando o processo democrático e a construção de uma sociedade plural e liberta.(AU)

This study aims to analyze traits of the potentially authoritarian mentality from the speech of Facebook users linked to political pages self-declared as rightist and leftist in Brazil. Netnography is used as a methodological contribution for online immersion in the pages "Eu era Direita e não sabia" and "Jovens de Esquerda" selected via Facebook Audience Insights, a tool provided by Facebook. From these, eight posts with greater engagement (number of comments, likes and shares), identified by Netvizz, were extracted. We collected 3,489 comments, which were organized in a textual corpus submitted to IRAMUTEQ software and analyzed from the perspective of immanent critical analysis of Critical Theory. As a result, we present the way in which authoritarian thinking manifests itself in the rationalization of contemporary society and in discursive practices in online social networks, rooted in the Brazilian socio-political sphere, threatening the democratic process and the construction of a plural and free society.(AU)

Este estudio tiene como objetivo analizar las huellas de la mentalidad potencialmente autoritaria a partir de los discursos de usuarios en Facebook vinculados a páginas políticas autodeclaradas de derecha y de izquierda en Brasil. La netnografía se utiliza como marco metodológico para la inmersión en línea en las páginas "Eu era Direita e não sabia" y "Jovens de Esquerda", seleccionadas por Facebook Audience Insights, herramienta proporcionada por Facebook. Se extrajeron las ocho publicaciones con mayor compromiso (número de comentarios, gustos y compartidas), identificadas por Netvizz. Se recogieron 3.489 comentarios, los cuales fueron organizados en un corpus textual sometido al software IRAMUTEQ y analizado bajo la perspectiva del análisis crítico inmanente de la teoría crítica. Los resultados presentan la forma en que el pensamiento autoritario se manifiesta en la racionalización de la sociedad contemporánea y en prácticas discursivas en redes sociales en línea, arraigada en el ámbito sociopolítico brasileño, que amenazan el proceso democrático y la construcción de una sociedad plural y liberada.(AU)

Adaptação acadêmica em universitários / Academic adaptation in university students / Adaptación académica en estudiantes universitários

O objetivo do estudo foi investigar o impacto das variáveis habilidades sociais, resolução de problemas sociais, automonitoria, autoeficácia e coping na adaptação acadêmica em estudantes de instituições de ensino superior públicas e privadas. Participaram 637 estudantes de ambos os sexos, sendo 36,5% (115) homens de instituições públicas e 22,3% (72) de instituições privadas, com idade variando entre 18 e 38 anos (M=24,7; DP=6,3), de diferentes graduações. Foram utilizados o Inventário de Resolução de Problemas Sociais, o Inventário de Habilidades Sociais, a Escala de Automonitoria, a Escala de Autoeficácia Acadêmica de Estudantes do Ensino Superior, o Inventário de Estratégias de Coping e o Questionário de Vivências Acadêmicas-reduzido. A autoeficácia na gestão acadêmica (40,9%) e a autoafirmação na expressão de afeto positivo (13,7%) apresentaram maior impacto para os estudantes de instituições públicas e privadas, podendo contribuir com possíveis intervenções no processo de adaptação ao ensino superior. Pesquisas prospectivas podem investigar questões relacionadas a dados sociodemográficos.(AU)

The aim of the study was to investigate the impact of the variables Social Skills, Resolution of Social Problems, Self-monitoring, Self-efficacy and Coping on Academic Adaptation in students from public and private higher education institutions. 637 students of both sexes participated, being 36.5% (115) men from public institutions and 22.3% (72) from private institutions, aged between 18 to 38 years (M = 24.7; SD = 6.3), of different grades. The Social Problem Solving Inventory, the Social Skills Inventory, the Self-Monitring Scale, the Higher Education Students' Academic Self-Efficacy Scale, the Coping Strategies Inventory and the Academic Experiences-Reduced Questionnaire were used. Self-efficacy in Academic Management (40.9%) and Self-affirmation in the Expression of Positive Affection (13.7%) had a greater impact on students from public and private institutions, which may contribute to possible interventions in the process of adapting to Higher Education. Prospective research can investigate issues related to sociodemographic data.(AU)

El objetivo del estudio fue investigar el impacto de las variables Habilidades sociales, Resolución de problemas sociales, Autocontrol, Autoeficacia y Afrontamiento en la adaptación académica en estudiantes de instituciones de educación superior públicas y privadas. Participaron 637 estudiantes de ambos sexos, siendo 36,5% (115) hombres de instituciones públicas y 22,3% (72) de instituciones privadas, con edades entre 18 y 38 años (M = 24,7; SD = 6,3), de diferentes grados. Se utilizaron el Inventario de Resolución de Problemas Sociales, el Inventario de Habilidades Sociales, la Escala de Autocontrol, la Escala de Autoeficacia Académica de los Estudiantes de Educación Superior, el Inventario de Estrategias de Afrontamiento y el Cuestionario de Experiencias Académicas Reducidas. La Autoeficacia en la Gestión Académica (40,9%) y la Autoafirmación en la Expresión de Afecto Positivo (13,7%) tuvieron un mayor impacto en los estudiantes de instituciones públicas y privadas, lo que puede contribuir a posibles intervenciones en el proceso de adaptación a la Educación Superior. La investigación prospectiva puede investigar cuestiones relacionadas con los datos sociodemográficos.(AU)

PsicoQuilombologia: escrevivência de uma psicologia das encruzilhadas em tempos pandêmicos / PsychoQuilombology: writexperience of a psychology of crossroads in pandemic times / PsicoQuilombología: escrivivencia de una psicología de la encrucijada en tiempos pandémicos

O texto é um relato de experiência da participação no Grupo de Estudos psicoQuilombologia ocorrida nos meses de setembro de 2020 a março de 2021, período atravessado pela segunda onda da pandemia de COVID-19 no Brasil. O objetivo do relato é apresentar o conceito-movimento de psicoQuilombologia como uma proposta epistemológica quilombola de agenciamento de cuidado e saúde, com base em uma escuta que se faça descolonial e inspirada no fecundo e ancestral acervo de cuidado dos povos africanos, quilombolas e pretos, preservado e atualizado em nossos quilombos contemporâneos. A metodologia utilizada é a escrevivência, método desenvolvido por Conceição Evaristo que propõe uma escrita em que as vivência e memórias estão totalmente entrelaçadas, imersas e imbricadas com a pesquisa. O resultado das escrevivências dessa pesquisa descortinam que os povos pretos desenvolveram práticas de cuidado e acolhimento às vulnerabilidades do outro, enraizadas no fortalecimento de laços e conexões coletivas de afetos e cuidado mútuos. Práticas de cuidado que articulam memória, ancestralidade, tradição, comunidade, transformação, luta, resistência e emancipação, engendrando modos coletivos de ser e viver. Nas quais cuidar do outro implica tratar suas relações e situar o cuidado como extensão de uma cura que se agencia no coletivo. O trabalho conclui apontando que o cenário pandêmico vigente acentua a pungência de se desenvolver estratégias de cuidado baseadas em epistemologias pretas e quilombolas, valorizando os sentidos de ancestralidade, comunidade, pertencimento e emancipação.(AU)

The text is an experience report of the participation in the psicoQuilombology Study Group that carried out from September 2020 to March 2021, during the second wave of the COVID-19 pandemic in Brazil. The purpose of the report is to introduce the concept-movement of psicoQuilombology as a quilombola epistemological proposal for the development of care and health, based on a decolonial listening and inspired by the rich care collection of African peoples, quilombolas and Blacks, preserved and updated in our contemporary quilombos. The methodology used is writexperience [escrevivências], a method developed by Conceição Evaristo who proposes a writing in that the experiences and memories are totally involved with the research. The result of the writability of this research show that Black people have developed practices of care and acceptance of the other's vulnerabilities, based on the strengthening of ties and collective connections of mutual affection and care. Care practices that mix memory, ancestry, tradition, community, transformation, struggle, resistance and emancipation, outlining collective ways of being and living. The core idea is that taking care of the other means treating your relationships and maintaining care as an extension of a cure that takes place in the collective. The paper concludes by pointing out that the current pandemic scenario demonstrates the urgent need to develop care strategies based on black and quilombola epistemologies, valuing the senses of ancestry, community, belonging and emancipation.(AU)

Este es un reporte de experiencia de la participación en el Grupo de Estudio psicoQuilombología que ocurrió en los meses de septiembre de 2020 a marzo de 2021, periodo en que Brasil afrontaba la segunda ola de la pandemia de la COVID-19. Su propósito es presentar el concepto-movimiento de psicoQuilombología como una propuesta epistemológica quilombola para el desarrollo del cuidado y la salud, basada en una escucha decolonial e inspirada en el rico acervo asistencial de los pueblos africanos, quilombolas y negros, conservado y actualizado en nuestros quilombos contemporáneos. La metodología utilizada es la escrivivencia, un método desarrollado por Conceição Evaristo quien propone una escrita en que las vivencias y los recuerdos están totalmente involucrados con la investigación. El resultado de la escrivivencia muestra que las personas negras han desarrollado prácticas de cuidado y aceptación de las vulnerabilidades del otro, basadas en el fortalecimiento de lazos y conexiones colectivas de afecto y cuidado mutuos. Prácticas de cuidado que mezclan memoria, ascendencia, tradición, comunidad, transformación, lucha, resistencia y emancipación, perfilando formas colectivas de ser y vivir. El cuidar al otro significa tratar sus relaciones y mantener el cuidado como una extensión de una cura que tiene lugar en lo colectivo. El trabajo concluye que el actual escenario pandémico demuestra la urgente necesidad de desarrollar estrategias de atención basadas en epistemologías negras y quilombolas, y que valoren los sentidos de ascendencia, comunidad, pertenencia y emancipación.(AU)

Impaired immune function accompanies social evolution in spiders.

An efficient immune system is essential to the survival of many animals. Sociality increases risk of pathogen transmission, which should select for enhanced immune function. However, two hypotheses instead predict a weakened immune function: relaxed selection caused by social immunity/protection, and reduced efficacy of selection due to inbreeding, reproductive skew and female bias in social species that reduce effective population size and accelerate genetic drift. We assessed the effect of social evolution on immune function in a comparative study of two social spider species and their closely related subsocial sister species (genus Stegodyphus). The haemolymph of social species was less efficient in inhibiting bacterial growth of the potentially pathogenic bacteria Bacillus subtilis than that of subsocial species. Reduced efficacy of selection in social species was supported by comparative genomic analysis showing substantially elevated non-synonymous substitutions in immune genes in one of the social species. We propose that impaired immune function results from reduced efficacy of selection because the evolution of sociality in spiders is accompanied by demographic processes that elevate genetic drift. Positive feedback between pathogen-induced local extinctions and the resulting elevation of genetic drift may further weaken responses to selection by pathogens, and threaten species persistence.

Evolution-proof inhibitors of public good cooperation: a screening strategy inspired by social evolution theory.

Interference with public good cooperation provides a promising novel antimicrobial strategy since social evolution theory predicts that resistant mutants will be counter-selected if they share the public benefits of their resistance with sensitive cells in the population. Although this hypothesis is supported by a limited number of pioneering studies, an extensive body of more fundamental work on social evolution describes a multitude of mechanisms and conditions that can stabilize public behaviour, thus potentially allowing resistant mutants to thrive. In this paper we theorize on how these different mechanisms can influence the evolution of resistance against public good inhibitors. Based hereon, we propose an innovative 5-step screening strategy to identify novel evolution-proof public good inhibitors, which involves a systematic evaluation of the exploitability of public goods under the most relevant experimental conditions, as well as a careful assessment of the most optimal way to interfere with their action. Overall, this opinion paper is aimed to contribute to long-term solutions to fight bacterial infections.

[Occupational medicine, witness to social evolution]. / La médecine du travail : témoin de l'évolution sociale.

Occupational medicine, witness to the industrial and economic evolution of societies, has observed over time the link between diseases and occupational exposures. Nowadays, the transformation of societies brings out new risks, modulated by technical and organizational changes, and our knowledge of their impact on health is constantly evolving. The role of the occupational physician has not changed: he must question and observe in order to know and understand. Its purpose is the same, to prevent workers from falling ill because of their work. It remains essential to pay particular attention to the search for professional factors that may have influenced the disease since the identification and management of the cause is often the best treatment.

La médecine du travail, témoin de l'évolution industrielle et économique des sociétés, s'est intéressée au fil du temps au lien entre les maladies et les expositions professionnelles. De nos jours, la transformation des sociétés fait émerger de nouveaux risques, modulés par les changements techniques et organisationnels, et nos connaissances de leurs impacts sur la santé sont en constante évolution. Le rôle du médecin du travail n'a pas changé : il doit questionner et observer pour connaître et comprendre. Son but reste le même, éviter que les travailleurs ne tombent malades à cause de leur travail. Il demeure primordial d'accorder une attention particulière à la recherche de facteurs professionnels ayant pu influencer la maladie puisque l'identification et la gestion de la cause représentent bien souvent le meilleur traitement.

Social evolution of shared biofilm matrix components.

Biofilm formation is an important and ubiquitous mode of growth among bacteria. Central to the evolutionary advantage of biofilm formation is cell-cell and cell-surface adhesion achieved by a variety of factors, some of which are diffusible compounds that may operate as classical public goods-factors that are costly to produce but may benefit other cells. An outstanding question is how diffusible matrix production, in general, can be stable over evolutionary timescales. In this work, using Vibrio cholerae as a model, we show that shared diffusible biofilm matrix proteins are indeed susceptible to cheater exploitation and that the evolutionary stability of producing these matrix components fundamentally depends on biofilm spatial structure, intrinsic sharing mechanisms of these components, and flow conditions in the environment. We further show that exploitation of diffusible adhesion proteins is localized within a well-defined spatial range around cell clusters that produce them. Based on this exploitation range and the spatial distribution of cell clusters, we constructed a model of costly diffusible matrix production and related these length scales to the relatedness coefficient in social evolution theory. Our results show that production of diffusible biofilm matrix components is evolutionarily stable under conditions consistent with natural biofilm habitats and host environments. We expect the mechanisms revealed in this study to be relevant to other secreted factors that operate as cooperative public goods in bacterial communities and the concept of exploitation range and the associated analysis tools to be generally applicable.

A influência da intervenção precoce no desenvolvimento motor, cognitivo e social de bebês de risco / The influence of early intervention in motor, cognitive and social development of risk babies

Verificar a influência da Atenção Precoce (AP) no desenvolvimento de bebês nos aspectos motores, cognitivos e sociais de bebês de risco que participam do programa de intervenção motora precoce (PIMP). Materiais e Métodos: Trata-se de um estudo ex post facto. A coleta de dados foi realizada em uma Clínica de Fisioterapia e a amostra foi composta por sete bebês de ambos os sexos que realizaram por quatro meses atendimentos de AP, duas vezes por semana, por 50 minutos. As atividades realizadas perfazem o campo motor, cognitivo e social. Resultados: O grupo foi homogêneo em relação às características. As atividades referentes à postura e deslocamento melhorou em 85% dos bebês, exploração de objetos manualmente em 71% e o reconhecimento da função de objetos 57%. A atividade de execução de tarefas a pedido foi a que menos os bebês evoluíram (57%). Conclusão: A intervenção precoce traz benefícios sobre o desenvolvimento motor e social dos bebês de risco. O desenvolvimento cognitivo, que representa tarefas com mais redes neuronais envolvidas, necessita de mais tempo para ser avaliada. (AU)

To verify the influence of Early Attention (AP) on the development of infants in the motor, cognitive and social aspects of at-risk babies participating in the Early Motor Intervention Program (PIMP). Materials and Methods: This is an ex post facto study. Data collection was performed at a Physiotherapy Clinic and the sample consisted of seven infants of both sexes who underwent AP appointments twice a week for 50 minutes. The activities carried out comprise the motor, cognitive and social fields. Results: The group was homogeneous in relation to the characteristics. The activities related to posture and displacement, improved in 85% of the babies, exploitation of objects manually by 71% and recognition of the function of objects by 57%. The on-task task activity was the one with the least babies (57%). Conclusion: Early intervention brings benefits to the motor and social development of at-risk babies. Cognitive development, which represents tasks with more neural networks involved, requires more time to be evaluated. (AU)

Social behavior mediates the use of social and personal information in wild jays.

The factors favoring the evolution of certain cognitive abilities in animals remain unclear. Social learning is a cognitive ability that reduces the cost of acquiring personal information and forms the foundation for cultural behavior. Theory predicts the evolutionary pressures to evolve social learning should be greater in more social species. However, research testing this theory has primarily occurred in captivity, where artificial environments can affect performance and yield conflicting results. We compared the use of social and personal information, and the social learning mechanisms used by wild, asocial California scrub-jays and social Mexican jays. We trained demonstrators to solve one door on a multi-door task, then measured the behavior of naïve conspecifics towards the task. If social learning occurs, observations of demonstrators will change the rate that naïve individuals interact with each door. We found both species socially learned, though personal information had a much greater effect on behavior in the asocial species while social information was more important for the social species. Additionally, both species used social information to avoid, rather than copy, conspecifics. Our findings demonstrate that while complex social group structures may be unnecessary for the evolution of social learning, it does affect the use of social versus personal information.

A Synthesis of Game Theory and Quantitative Genetic Models of Social Evolution.

Two popular approaches for modeling social evolution, evolutionary game theory and quantitative genetics, ask complementary questions but are rarely integrated. Game theory focuses on evolutionary outcomes, with models solving for evolutionarily stable equilibria, whereas quantitative genetics provides insight into evolutionary processes, with models predicting short-term responses to selection. Here we draw parallels between evolutionary game theory and interacting phenotypes theory, which is a quantitative genetic framework for understanding social evolution. First, we show how any evolutionary game may be translated into two quantitative genetic selection gradients, nonsocial and social selection, which may be used to predict evolutionary change from a single round of the game. We show that synergistic fitness effects may alter predicted selection gradients, causing changes in magnitude and sign as the population mean evolves. Second, we show how evolutionary games involving plastic behavioral responses to partners can be modeled using indirect genetic effects, which describe how trait expression changes in response to genes in the social environment. We demonstrate that repeated social interactions in models of reciprocity generate indirect effects and conversely, that estimates of parameters from indirect genetic effect models may be used to predict the evolution of reciprocity. We argue that a pluralistic view incorporating both theoretical approaches will benefit empiricists and theorists studying social evolution. We advocate the measurement of social selection and indirect genetic effects in natural populations to test the predictions from game theory and, in turn, the use of game theory models to aid in the interpretation of quantitative genetic estimates.

Interacting phenotypes and the coevolutionary process: Interspecific indirect genetic effects alter coevolutionary dynamics.

Coevolution occurs when species interact to influence one another's fitness, resulting in reciprocal evolutionary change. In many coevolving lineages, trait expression in one species is modified by the genotypes and phenotypes of the other, forming feedback loops reminiscent of models of intraspecific social evolution. Here, we adapt the theory of within-species social evolution, characterized by indirect genetic effects and social selection imposed by interacting individuals, to the case of interspecific interactions. In a trait-based model, we derive general expressions for multivariate evolutionary change in two species and the expected between-species covariance in evolutionary change when selection varies across space. We show that reciprocal interspecific indirect genetic effects can dominate the coevolutionary process and drive patterns of correlated evolution beyond what is expected from direct selection alone. In extreme cases, interspecific indirect genetic effects can lead to coevolution when selection does not covary between species or even when one species lacks genetic variance. Moreover, our model indicates that interspecific indirect genetic effects may interact in complex ways with cross-species selection to determine the course of coevolution. Importantly, our model makes empirically testable predictions for how different forms of reciprocal interactions contribute to the coevolutionary process.

Genomic and transcriptomic analyses of the subterranean termite Reticulitermes speratus: Gene duplication facilitates social evolution.

Termites are model social organisms characterized by a polyphenic caste system. Subterranean termites (Rhinotermitidae) are ecologically and economically important species, including acting as destructive pests. Rhinotermitidae occupies an important evolutionary position within the clade representing a transitional taxon between the higher (Termitidae) and lower (other families) termites. Here, we report the genome, transcriptome, and methylome of the Japanese subterranean termite Reticulitermes speratus Our analyses highlight the significance of gene duplication in social evolution in this termite. Gene duplication associated with caste-biased gene expression was prevalent in the R. speratus genome. The duplicated genes comprised diverse categories related to social functions, including lipocalins (chemical communication), cellulases (wood digestion and social interaction), lysozymes (social immunity), geranylgeranyl diphosphate synthase (social defense), and a novel class of termite lineage-specific genes with unknown functions. Paralogous genes were often observed in tandem in the genome, but their expression patterns were highly variable, exhibiting caste biases. Some of the assayed duplicated genes were expressed in caste-specific organs, such as the accessory glands of the queen ovary and the frontal glands of soldier heads. We propose that gene duplication facilitates social evolution through regulatory diversification, leading to caste-biased expression and subfunctionalization and/or neofunctionalization conferring caste-specialized functions.