A field guide for teaching evolution in the social sciences

The theory of evolution by natural selection has begun to revolutionize our understanding of perception, cognition, language, social behavior, and cultural practices. Despite the centrality of evolutionary theory to the social sciences, many students, teachers, and even scientists struggle to understand how natural selection works. Our goal is to provide a field guide for social scientists on teaching evolution, based on research in cognitive psychology, developmental psychology, and education. We synthesize what is known about the psychological obstacles to understanding evolution, methods for assessing evolution understanding, and pedagogical strategies for improving evolution understanding. We review what is known about teaching evolution about nonhuman species and then explore implications of these findings for the teaching of evolution about humans. By leveraging our knowledge of how to teach evolution in general, we hope to motivate and equip social scientists to begin teaching evolution in the context of their own field.     

Joining forces: feedback and integration in plant development

Feedback and integration of information are of paramount importance for the robust functioning and dynamics of biological systems. In plant developmental biology, experimentation is increasingly combined with computational modeling to obtain a better understanding of how such regulatory interactions shape the systems' behavior. Here we highlight experimental and modeling studies on feedback loops and integration mechanisms involved in plant development. These studies have substantially expanded our understanding of previously characterized gene regulatory networks (GRNs). In addition, they illustrate the pervasiveness of regulatory interactions between seemingly unrelated processes and levels of organization. Modelers in plant development will increasingly face the challenges of what level of detail, which processes and how many levels of organization to incorporate when trying to understand a particular process.     

Pocahontas Goes to the Clinic: Popular Culture as Lingua Franca in a Cultural Borderland

Urban hospitals constitute an example of what is arguably the most visible site in anthropology these days—the border zone. Negotiating health care requires trafficking in tricky spaces where patients and their families must pay vigilant attention about when to submit, when to resist, and how to collaborate. Drawing from ethnographic research carried out over the past nine years among African American families who have children with severe illnesses and disabilities, I examine how children's popular culture operates in the fraught borderland that constitutes the urban clinic. Global icons like a Disneyfied Pocahantas can function as a lingua franca, offering a language of publicly available symbols on which families, health professionals, and children can draw to create a shared imaginative space across race and class divides and across the sometimes even more radical divide between sufferer and healer.     

Linking social identity,risk perception,and behavioral psychology to understand predator management by livestock producers

Human behaviors can determine the success of efforts to restore predators to ecosystems. While behaviors such as lethal predator control may impede predator restoration, other land management practices can facilitate coexistence between predators and humans. Socio‐psychological theories provide useful tools for understanding and improving these human behaviors. We explore three frameworks to understand what shapes Australian livestock graziers' behaviors with regards to management of the threat that dingoes pose to livestock. These frameworks are the theory of reasoned action (incorporating values and beliefs about dingoes), the social identity approach, and perception of risk. We distributed a survey to Australian graziers by mail and online (n = 138) which allowed recording of information on these three frameworks and their engagement in lethal dingo control. Among the respondents, we found that all three frameworks were linked with lethal dingo control when assessed individually, but when combined in a hierarchical regression, only social identity (specifically, identifying as an “environmentalist” or “pest controller”) was significant in predicting behavior. This result reveals the strength of social norms and normative beliefs over perceived risk in shaping behavior. As such, social identity is a useful metric for predicting and understanding environmental management behavior. Determining what these social identities mean in a given context is important for identifying how to implement behavior change to promote evidence‐based management that facilitates restoration of wildlife such as predators to landscapes where conflict with humans occurs.     

Opening the Black Box of Developmental Experiments: Behavioural Mechanisms Underlying Long‐Term Effects of Early Social Experience

Typically, animals spend a considerable portion of their time with social interactions involving mates, offspring, competitors and group members. The social performance during these interactions can strongly depend on the social environment individuals have experienced early in life. Despite a considerable number of experiments investigating long‐term effects of the early social environment, our understanding of the behavioural mechanisms mediating these effects is still limited, mainly for two reasons. (1) Only in few experimental studies have researchers actually observed and quantified the behaviour of their study animals during the social treatment. (2) Even if differences in social interactions between social rearing treatments are reported, these differences might not be causally linked to any observed long‐term effects later in life. The aim of this review was to investigate whether behavioural records of animals during the experimental manipulation of their social environment can help (1) identifying behavioural mechanisms involved in a long‐term effect and (2) obtaining a better understanding of the long‐term consequences of early manipulations. First, I review studies that manipulated the social environment at an early stage of the ontogeny, observed the social interactions and behaviour during the social experience phase and subsequently tested the performance in social and non‐social behavioural tasks at a later life stage. In all reviewed studies, treatment differences were reported both in social interactions during the social experience phase and in social and/or non‐social behaviours later in life. Second, I discuss four classes of behavioural mechanisms that can cause the reported long‐term effects of social experience, namely learning by experience, social learning, sensory stimulation and social cueing. I conclude that social interactions during the social experience phase should always be recorded for at least two reasons. Knowledge about how the social interactions differ between rearing treatments (1) permits researchers to formulate hypotheses about candidate mechanisms causing long‐term effects on behaviour and (2) can help to interpret unexpected outcomes of developmental experiments. Finally, I propose that as a crucial ultimate step towards understanding effects of the early social environment, we should develop targeted experiments testing for the causality of identified candidate mechanism.     

The neurogenetics of sexually dimorphic behaviors from a postdevelopmental perspective

Most sexually reproducing animal species are characterized by two morphologically and behaviorally distinct sexes. The genetic, molecular and cellular processes that produce sexual dimorphisms are phylogenetically diverse, though in most cases they are thought to occur early in development. In some species, however, sexual dimorphisms are manifested after development is complete, suggesting the intriguing hypothesis that sex, more generally, might be considered a continuous trait that is influenced by both developmental and postdevelopmental processes. Here, we explore how biological sex is defined at the genetic, neuronal and behavioral levels, its effects on neuronal development and function, and how it might lead to sexually dimorphic behavioral traits in health and disease. We also propose a unifying framework for understanding neuronal and behavioral sexual dimorphisms in the context of both developmental and postdevelopmental, physiological timescales. Together, these two temporally separate processes might drive sex‐specific neuronal functions in sexually mature adults, particularly as it pertains to behavior in health and disease.     

Social neuroscience and its potential contribution to psychiatry

Most mental disorders involve disruptions of normal social behavior. Social neuroscience is an interdisciplinary field devoted to understanding the biological systems underlying social processes and behavior, and the influence of the social environment on biological processes, health and well‐being. Research in this field has grown dramatically in recent years. Active areas of research include brain imaging studies in normal children and adults, animal models of social behavior, studies of stroke patients, imaging studies of psychiatric patients, and research on social determinants of peripheral neural, neuroendocrine and immunological processes. Although research in these areas is proceeding along largely independent trajectories, there is increasing evidence for connections across these trajectories. We focus here on the progress and potential of social neuroscience in psychiatry, including illustrative evidence for a rapid growth of neuroimaging and genetic studies of mental disorders. We also argue that neuroimaging and genetic research focused on specific component processes underlying social living is needed.     

Learning and Behavior in Reef Fish: Fuel for Microevolutionary Change?

Small‐scale population differentiation among coral reef fishes may be more common than previously thought. New molecular technologies have informed patterns of differentiation, while experimental approaches focusing on larval abilities to limit distribution have explored processes leading to diversification. Building upon a recently published paper by Wismer et al. that examined population level differences in learning and cooperative behaviors in cleaner wrasse (Labroides dimidiatus), we use a phylogenetic framework to explore how social behaviors are distributed among wrasses in the Labrichthyines clade. Establishing links between social behavior and speciation across the phylogeny allows us explore how social behaviors such as learning and cooperation may also act as possible mechanisms driving diversification at the microevolutionary scale.     

Social plasticity in fish: integrating mechanisms and function

Social plasticity is a ubiquitous feature of animal behaviour. Animals must adjust the expression of their social behaviour to the nuances of daily social life and to the transitions between life‐history stages, and the ability to do so affects their Darwinian fitness. Here, an integrative framework is proposed for understanding the proximate mechanisms and ultimate consequences of social plasticity. According to this framework, social plasticity is achieved by rewiring or by biochemically switching nodes of the neural network underlying social behaviour in response to perceived social information. Therefore, at the molecular level, it depends on the social regulation of gene expression, so that different brain genomic and epigenetic states correspond to different behavioural responses and the switches between states are orchestrated by signalling pathways that interface the social environment and the genotype. At the evolutionary scale, social plasticity can be seen as an adaptive trait that can be under positive selection when changes in the environment outpace the rate of genetic evolutionary change. In cases when social plasticity is too costly or incomplete, behavioural consistency can emerge by directional selection that recruits gene modules corresponding to favoured behavioural states in that environment. As a result of this integrative approach, how knowledge of the proximate mechanisms underlying social plasticity is crucial to understanding its costs, limits and evolutionary consequences is shown, thereby highlighting the fact that proximate mechanisms contribute to the dynamics of selection. The role of teleosts as a premier model to study social plasticity is also highlighted, given the diversity and plasticity that this group exhibits in terms of social behaviour. Finally, the proposed integrative framework to social plasticity also illustrates how reciprocal causation analysis of biological phenomena (i.e. considering the interaction between proximate factors and evolutionary explanations) can be a more useful approach than the traditional proximate–ultimate dichotomy, according to which evolutionary processes can be understood without knowledge on proximate causes, thereby black‐boxing developmental and physiological mechanisms.     

Individual acquisition of “stick pounding” behavior by naïve chimpanzees

Many studies investigating culture in nonhuman animals tend to focus on the inferred need of social learning mechanisms that transmit the form of a behavior to explain the population differences observed in wild animal behavioral repertoires. This research focus often results in studies overlooking the possibility of individuals being able to develop behavioral forms without requiring social learning. The disregard of individual learning abilities is most clearly observed in the nonhuman great ape literature, where there is a persistent claim that chimpanzee behaviors, in particular, require various forms of social learning mechanisms. These special social learning abilities have been argued to explain the acquisition of the relatively large behavioral repertoires observed across chimpanzee populations. However, current evidence suggests that although low‐fidelity social learning plays a role in harmonizing and stabilizing the frequency of behaviors within chimpanzee populations, some (if not all) of the forms that chimpanzee behaviors take may develop independently of social learning. If so, they would be latent solutions—behavioral forms that can (re‐)emerge even in the absence of observational opportunities, via individual (re)innovations. Through a combination of individual and low‐fidelity social learning, the population‐wide patterns of behaviors observed in great ape species are then established and stably maintained. This is the Zone of Latent Solutions (ZLS) hypothesis. The current study experimentally tested the ZLS hypothesis for pestle pounding, a wild chimpanzee behavior. We tested the reinnovation of this behavior in semi‐wild chimpanzees at Chimfunshi Wildlife Orphanage in Zambia, Africa, (N = 90, tested in four social groups). Crucially, all subjects were naïve to stick pounding before testing. Three out of the four tested groups reinnovated stick pounding—clearly demonstrating that this behavioral form does not require social learning. These findings provide support for the ZLS hypothesis alongside further evidence for the individual learning abilities of chimpanzees.     

Developmental responses to early‐life adversity: Evolutionary and mechanistic perspectives

Adverse ecological and social conditions during early life are known to influence development, with rippling effects that may explain variation in adult health and fitness. The adaptive function of such developmental plasticity, however, remains relatively untested in long‐lived animals, resulting in much debate over which evolutionary models are most applicable. Furthermore, despite the promise of clinical interventions that might alleviate the health consequences of early‐life adversity, research on the proximate mechanisms governing phenotypic responses to adversity have been largely limited to studies on glucocorticoids. Here, we synthesize the current state of research on developmental plasticity, discussing both ultimate and proximate mechanisms. First, we evaluate the utility of adaptive models proposed to explain developmental responses to early‐life adversity, particularly for long‐lived mammals such as humans. In doing so, we highlight how parent‐offspring conflict complicates our understanding of whether mothers or offspring benefit from these responses. Second, we discuss the role of glucocorticoids and a second physiological system—the gut microbiome—that has emerged as an additional, clinically relevant mechanism by which early‐life adversity can influence development. Finally, we suggest ways in which nonhuman primates can serve as models to study the effects of early‐life adversity, both from evolutionary and clinical perspectives.     

The impact of water pH on association preferences in fish

Acidification of lakes and rivers, as a consequence of anthropogenic interference, can cause fundamental changes to biological and ecological processes. One of the main consequences of a reduction in water pH for aquatic organisms is the disruption of their chemosensory abilities, as the detection of chemical cues underpins a wide range of decision‐making processes; for example, a reduction to low pH has been shown to interfere with predator avoidance and the detection of foraging cues. Moreover, aquatic organisms are known to make widespread use of chemical information to inform their social behaviour, although we have a comparably poor understanding of how this is impacted by water acidification, especially their shoaling behaviour. Using a standard behavioural assay, we therefore investigated the impact of low water pH on the social interactions mediated by diet‐derived chemical cues in three‐spined sticklebacks (Gasterosteus aculeatus), by quantifying social behaviour in water that varied either experimentally or naturally in pH. In both cases, we predicted that association patterns would be disrupted by low pH conditions, as reduced pH has shown to interfere with the perception of chemical cues in other non‐social contexts. Consistent with this prediction, our results demonstrate that an acute, short‐term reduction in water pH caused a breakdown in the diet‐mediated social interaction patterns seen in more alkaline water, although, interestingly, the pattern of associations for fish tested in naturally acidic water was both more complex and in a direction that was precisely contrary to our predictions. Overall, the findings provide insights into the potential effects of an acute reduction in water pH on fish communication and social interaction patterns, which may have implication for various individual, group, population and community‐level processes.     

The brain and the law

Much has been written about how law as an institution has developed to solve many problems that human societies face. Inherent in all of these explanations are models of how humans make decisions. This article discusses what current neuroscience research tells us about the mechanisms of human decision making of particular relevance to law. This research indicates that humans are both more capable of solving many problems than standard economic models predict, but also limited in ways those models ignore. This article discusses how law is both shaped by our cognitive processes and also shapes them. The article considers some of the implications of this research for improving our understanding of how our current legal regimes operate and how the law can be structured to take advantage of our neural mechanisms to improve social welfare.     

Evo-devo and the evolution of social behavior

The integration of evolutionary biology with developmental genetics into the hybrid field of 'evo-devo' resulted in major advances in understanding multicellular development and morphological evolution. Here we show how insights from evo-devo can be applied to study the evolution of social behavior. We develop this idea by reviewing studies that suggest that molecular pathways controlling feeding behavior and reproduction in solitary insects are part of a 'genetic toolkit' underlying the evolution of a particularly complex form of social behavior, division of labor among workers in honeybee colonies. The evo-devo approach, coupled with advances in genomics for non-model genetic organisms, including the recent sequencing of the honeybee genome, promises to advance our understanding of the evolution of social behavior.     

Social influences on foraging behavior in young nonhuman primates: Learning what,where, and how to eat

Human infants rely on social interactions to acquire food‐related information. 1 , 2 Adults actively teach children about food through culturally diverse feeding practices. Characteristics we share with the other primates, such as complex diets, highly social lives, and extended juvenile periods, suggest that social learning may be important during ontogeny throughout the order. Although all young primates typically pay attention to feeding adults, great apes and callitrichids, in particular, acquire new foraging techniques through abilities unknown in other nonhuman primates; that is, they learn by imitation. However, ape social learning is almost exclusively infant‐initiated, while adult callitrichids actively teach their young. It is unlikely that the same selective forces have acted to favor sophisticated social‐learning mechanisms in both taxa. 3 , 4 Equipped with an ape brain, complex foraging methods, and a cooperative infant‐care system, early hominins were uniquely poised to take social learning about food and foraging techniques to a new level.     

Voice processing in human and non-human primates

Humans share with non-human primates a number of voice perception abilities of crucial importance in social interactions, such as the ability to identify a conspecific individual from its vocalizations. Speech perception is likely to have evolved in our ancestors on the basis of pre-existing neural mechanisms involved in extracting behaviourally relevant information from conspecific vocalizations (CVs). Studying the neural bases of voice perception in primates thus not only has the potential to shed light on cerebral mechanisms that may be--unlike those involved in speech perception--directly homologous between species, but also has direct implications for our understanding of how speech appeared in humans. In this comparative review, we focus on behavioural and neurobiological evidence relative to two issues central to voice perception in human and non-human primates: (i) are CVs 'special', i.e. are they analysed using dedicated cerebral mechanisms not used for other sound categories, and (ii) to what extent and using what neural mechanisms do primates identify conspecific individuals from their vocalizations?     

Developmental experiences and the oxytocin receptor system

The long-term effects of developmental experiences on social behavior, and the neuropeptide systems such as oxytocin which subserve the behavior, are still little understood. In this article, we review various types of early experience, including normal development, knockout models, pharmacological exposures, and early social experiences. We consider the processes by which experience can affect oxytocin receptor binding, and what is known about the directionality of experience effects on oxytocin receptors. Finally, we attempt to synthesize the literature into a predictive model as to the direction of early experience effects on oxytocin receptor binding potential, and whether these changes have functional significance. These predictions are relevant to current human health practice, given proposals to use chronic intranasal oxytocin to treat developmental disorders including autism and schizophrenia. This article is part of a Special Issue entitled Oxytocin, Vasopressin, and Social Behavior.     

Lamarck rises from his grave: parental environment‐induced epigenetic inheritance in model organisms and humans

Organisms can change their physiological/behavioural traits to adapt and survive in changed environments. However, whether these acquired traits can be inherited across generations through non‐genetic alterations has been a topic of debate for over a century. Emerging evidence indicates that both ancestral and parental experiences, including nutrition, environmental toxins, nurturing behaviour, and social stress, can have powerful effects on the physiological, metabolic and cellular functions in an organism. In certain circumstances, these effects can be transmitted across several generations through epigenetic (i.e. non‐DNA sequence‐based rather than mutational) modifications. In this review, we summarize recent evidence on epigenetic inheritance from parental environment‐induced developmental and physiological alterations in nematodes, fruit flies, zebrafish, rodents, and humans. The epigenetic modifications demonstrated to be both susceptible to modulation by environmental cues and heritable, including DNA methylation, histone modification, and small non‐coding RNAs, are also summarized. We particularly focus on evidence that parental environment‐induced epigenetic alterations are transmitted through both the maternal and paternal germlines and exert sex‐specific effects. The thought‐provoking data presented here raise fundamental questions about the mechanisms responsible for these phenomena. In particular, the means that define the specificity of the response to parental experience in the gamete epigenome and that direct the establishment of the specific epigenetic change in the developing embryos, as well as in specific tissues in the descendants, remain obscure and require elucidation. More precise epigenetic assessment at both the genome‐wide level and single‐cell resolution as well as strategies for breeding at relatively sensitive periods of development and manipulation aimed at specific epigenetic modification are imperative for identifying parental environment‐induced epigenetic marks across generations. Considering their diverse epigenetic architectures, the conservation and prevalence of the mechanisms underlying epigenetic inheritance in non‐mammals require further investigation in mammals. Interpretation of the consequences arising from epigenetic inheritance on organisms and a better understanding of the underlying mechanisms will provide insight into how gene–environment interactions shape developmental processes and physiological functions, which in turn may have wide‐ranging implications for human health, and understanding biological adaptation and evolution.     

Childhood Obesity: Do Parents Recognize This Health Risk?

Objective: This study examined parents’ understanding of excess weight as a health risk, knowledge of healthy eating habits, and recognition of obesity in their children. Research Methods and Procedures: An anonymous questionnaire was distributed during well‐care visits involving children 4 to 8 years of age at a pediatric faculty practice. Parents indicated their level of concern about excess weight and other familiar health risks using a four‐point Likert scale, answered multiple‐choice questions concerning healthy eating patterns, and communicated their perceptions about their child's weight using a visual analog scale. A parent's perception was considered “accurate” if it deviated from the child's growth chart percentile by <30 points. Results: Of the 83 parents surveyed, 23% (19/83) had overweight children (≥95th percentile of age‐ and gender‐specific BMI growth charts). These parents did not differ from other parents in their level of concern about excess weight as a health risk or in their knowledge of healthy eating patterns, but the two groups of parents did differ in the accuracy of their perceptions about their children's weight. Only 10.5% of parents of overweight children (2/19) perceived their child's weight accurately compared with 59.4% of other parents (38/64; p < 0.001). Parents of overweight children invariably underestimated their children's weight. The median difference between their perception and the growth chart percentile was ?45 points. Discussion: Given that most parents of overweight children fail to recognize that their child has a weight problem, pediatricians should develop strategies to help these parents correct their misperceptions.