Center for Behavior, Evolution, and Culture

Adam Sparks - Who takes risks, and why?
2017-03-06 00:00 (America/Los_Angeles)
Adam Sparks: UCLAWho takes risks, and why? Does risk-taking in one context predict risk-taking in other contexts? Attempting to answer these questions, I present a general conceptual model of decision-making under risk that integrates two inter-related pathways to risk-taking. The need-based pathway describes strategic response to competitive disadvantages; the ability-based pathway exploits competitive advantages. This broad model may help to reconcile long-standing disagreements regarding the etiology of risk-taking, especially debates between advocates of domain-general or domain-specific approaches to risk. Further, collaborators and I have applied this model to generate and test novel predictions about individual differences in diverse psychological/behavioral phenomena: pathogen avoidance, mating preferences, moral judgment, and cooperation/conflict decisions. There remain many opportunities for integrating the evolutionarily-informed study of risk-taking with the study of putatively domain-specific psychological mechanisms (e.g. emotions) and behaviors.

Marco Del Giudice - A unifying framework for evolutionary psychopathology
2017-03-13 00:00
Marco Del Giudice: University of New MexicoEvolutionary approaches to psychopathology have generated many innovative models of specific mental disorders, as well as a growing empirical literature. However, the field as a whole remains highly fragmented, and has not yet produced a biologically grounded alternative to existing classification systems. In this talk I introduce a unifying framework for mental disorders based on life history concepts. The updated classification model I present distinguishes between fast spectrum conditions (e.g., antisocial/conduct disorders and schizophrenia), slow spectrum conditions (e.g., obsessive-compulsive personality disorder and a variant of autism), and defense activation disorders (e.g., depression and phobias). I illustrate how this approach can be used to draw functionally important distinctions within single diagnostic categories and make sense of broad patterns of comorbidity, developmental patterns, and epidemiological risk factors. Finally, I present simulation results showing that the life history model successfully reproduces the observed structure of mental disorders, including the internalizing-externalizing distinction and the emergence of a “p factor” of generalized susceptibility to psychopathology.

Jeffrey Schank - The Evolution of Fairness
2017-04-03 00:00
Jeffrey Schank: UC DavisThere are many theoretical approaches to explaining fairness, but explaining fairness without leverage (e.g., genetic relatedness, punishment, or retaliation) is especially challenging. The dictator game (DG) is a fairness game without leverage. One player, the dictator, is given a divisible quantity of some resource (typically money) and must decide how much to give a second player, the recipient. The recipient has no counter strategy, so the obvious rational solution to the DG is for the dictator to keep all of the resource and give none to the recipient. In experimental applications of the DG, to control for possible forms of leverage (e.g., relatedness, friendship, etc.), anonymity is maintained between players. Nevertheless, hundreds of experiments using the DG across cultures have shown that people, on average, share nearly 30% of a resource with an anonymous recipient. Theoretically, this result has proven difficult to explain because of the lack of leverage. For example, Hamilton’s rule, which is standardly used to explain altruism and cooperation at the level of the individual, does not formally apply. Using an agent-based model, I show that fairness can evolve among agents that naively and anonymously play the DG. I also show that this framework can be extended to its close cousin the ultimatum game, providing a better explanation of the available Empirical data than models that only rely on leverage.

Ketema Paul - The Ability to Recover from Sleep Loss is Regulated by Biological Clocks in Skeletal Muscle Tissue
2017-04-16 00:00
Ketema Paul: University of California, Los AngelesSleep loss can severely impair cognitive performance, yet the ability to recover from sleep loss is not well understood. Sleep regulatory mechanisms are assumed to lie exclusively within the brain mainly due to the strong behavioral manifestations of sleep. Whole-body disruptions of circadian biological clocks in mice are known to impair several aspects of sleep. Surprisingly, we found that circadian-dependent sleep phenotypes were not rescued by restoring clock function in the brains of these mice. Instead, we found that most of the impaired sleep phenotypes could be rescued by restoring circadian clock function exclusively in skeletal muscle. Additionally, selective overexpression or knockout of core circadian gene Bmal1 in skeletal muscle had distinct and opposing effects on sleep traits. The most robust effects of Bmal1 manipulation in skeletal muscle tissue were on the ability to recover from sleep loss. Overall, these results suggest that molecular mechanisms in the periphery in general, and skeletal muscle tissue in particular, have regulatory influences on sleep-wake mechanisms in the brain.

Chris Dunkel Schetter - Stress and Anxiety in Pregnancy: Consequences and Mechanisms for Birth and Beyond
2017-04-24 00:00
Chris Dunkel Schetter: University of California, Los AngelesIn this talk, Prof Dunkel Schetter will touch on conceptions of stress, background on birth outcomes, and summarize briefly findings on stress and preterm birth and low birthweight. She will present findings from her own program of work on pregnancy anxiety as a risk factor for preterm birth and the mechanisms in diverse ethnic, racial and SES women. She will also note some developmental effects of prenatal stress and anxiety, and briefly mention resilience to stress in pregnancy and intervention work.

Cristine H. Legare - The Evolution and Ontogeny of Cultural Learning
2017-05-01 00:00
Cristine H. Legare: University of Texas at AustinHumans display a wide repertoire of socially acquired and transmitted behaviors that vary substantially across populations. Information is accumulated and transferred within and across generations through the process of cumulative culture. What are the evolved psychological mechanisms that underlie cultural learning and how do they develop over the course of ontogeny? In a systematic program of mixed-methodological, comparative, and cross-cultural research, I study the human capacities to learn, create, and transmit culture, to shed light on the cognitive and cultural evolution of our species. The propensity for social learning provides the foundation for cumulative culture, and is both early developing and universal. Selective social learning mechanisms also afford the capacity to flexibly respond to diverse ontogenetic contexts and cultural ecologies. I describe the global diversity in childrearing practices, and present evidence for continuity and variability in the psychological capacities that enable cultural learning.

Kevin Langergraber - Group Augmentation, Collective Action, and Territorial Boundary Patrolling by Male Chimpanzees
2017-05-02 00:00
Kevin Langergraber: Arizona State UniversityMany animals carry out activities together because the benefits derived from collective action exceed those that can be achieved individually. But how can collective action evolve when individuals benefit from cooperation regardless of whether they pay its participation costs? According to one influential perspective, collective action problems are common, especially when groups are large, but may be solved when individuals who have more to gain from the collective good or can produce it at low costs provide it to others as a byproduct. Several results from a 20-year study of one of the most striking examples of collective action in non-human animals, territorial boundary patrolling by male chimpanzees, are consistent with these ideas: individual participation varied positively with both paternity success, i.e., the benefits, and dominance rank, i.e., a proxy for costs, and negatively with group size. Collective action theory nevertheless could not explain all our results because individual patrolling effort was higher and less variable than participation in intergroup aggression in other primate species, and males often patrolled when they had no offspring or maternal relatives in the group to protect. In addition, the aggregate patrolling effort of the group did not decrease with group size. These results are better explained by group augmentation theory, which proposes that individuals should bear the short-term costs of collective action even when they have little to gain immediately, if such action leads to increases in group size and ultimately long-term reproductive success.

Claudia Valeggia - Life history (and other) transitions among the Qom of Argentina
2017-05-08 00:00
Claudia Valeggia: UC DavisThis talk will be about change and how we experience it. Humans go through several transitions during the course of their life. The transition from one life history phase to the next, e.g. from infancy to childhood or from reproductive to post-reproductive life, represents a physiological challenge as well as a sociocultural one. We have been evaluating the interaction among biocultural variables underlying key life history transitions and identifying the implicated trade-offs. With a different analytical focus, we are also interested in exploring transitions at a population level, like the ones indigenous communities are experiencing all over the world. For the last 20 years, we have been working with Qom and other indigenous communities in northern Argentina. Biological and ethnographic data are combined to understand the theoretical and applied components of these life and population transitions. I will present an overview of what we have learned so far and share some of the contributions we have made to evolutionary anthropology, human biology, biocultural studies, and global public health.

Anita Stone - From Juveniles to Adults: Life History Challenges and Strategies of Squirrel Monkeys
2017-05-15 00:00
Anita Stone: California Lutheran UniversityThe primate juvenile period has been considered a “limbo phase” with few evolutionary consequences, a view that has been challenged. In addition, it has been proposed that juvenility is a high-risk stage in which juveniles are at social and ecological disadvantages compared to adults in their group. Using field data from a population of squirrel monkeys (Saimiri collinsi) in Eastern Amazonia, Brazil, I evaluate the “riskiness” of the juvenile phase. These neotropical primates are small, show delayed maturation, are frugivorous-insectivorous and live in large social groups. Contrary to expectations, juveniles are at no disadvantage compared to larger and older adults, both in terms of time needed to acquire foraging skills or in competitive interactions with older conspecifics. I argue that in this genus of neotropical primate, adults face higher sociecological risks associated with reproductive challenges than do juveniles. I will then discuss the distinct life history pressures that affect adult male and adult female squirrel monkeys.

Adrian Bell - Advancing Our Evolutionary Understanding of Migration
2017-05-22 00:00
Adrian Bell: University of UtahMost evolutionary ecological outcomes are highly sensitive to the nature of migration. The when, where, and how of migration are fundamental to evolutionary questions that anthropologists and others have tackled, though with varying levels of analytical rigor. In worst cases, migration is merely acknowledged as the elephant in the room. How can we do better! In this talk I discuss theoretical and empirical approaches that help us more rigorously explore the patterns of migration and measure its impact in prehistory and the present. I take examples from my theoretical work on the Ideal Despotic Distribution, ethnic markers, and the evolution of essentialism. I also discuss my empirical work on settlement patterns in the Pacific, and ongoing ethnographic work in Tonga and the Tongan diaspora. Throughout I advocate the balanced use of mathematical theory and empirical rigor as the way forward.

Peter B. Gray - Sex, Babies, and Dogs: Evolutionary and Endocrine Aspects of Changing Human Families
2017-06-05 00:00
Peter B. Gray: University of Nevada, Las VegasCompared to great apes, several key features of human hunter-gatherer family life stand out: having more children at shorter inter-birth intervals, forming long-term reproductive partnerships, and investment by fathers and female relatives beyond their reproductive years. Behavioral reconstructions suggest derived features of human hunter-gatherer families evolved during the last several million years of Homo. As humans spread around the globe, a marvelous variety of human families has emerged and continues to change. Life history theory provides a functional approach, complemented by hormonal mechanisms, to structure how family members interact among themselves and with others. I discuss several key patterns intertwining human family change and hormones that differ from hunter-gatherer families. Almost all human children today are involved in formal education and many too in sports and school-based competitions organized by adults. How do adrenal hormones DHEA and androstenedione relate to children’s learning and social competition? In great apes and hunter-gatherers, the bulk of female reproductive years are spent pregnant or in lactational amenorrhea. Yet fertility has plummeted in much of the world and inter-birth intervals differ from ancestral conditions. How do hormonal shifts across pregnancy and postpartum impact maternal care and partnership dynamics, including sex lives, of parents? Fathers play variable roles across human families. Male involvement in family life is often linked to lower testosterone, and also involves oxytocin and prolactin. In some societies, dogs are increasingly viewed as family members, with several studies indicating that interactions with a dog can increase human oxytocin levels. Lastly, I speculate about patterns of female and male reproductive senescence and underlying hormonal mechanisms in relation to partnership maintenance and grandparenting.

William Audeh - Applying Evolutionary Biology to Make Progress in Cancer Medicine
2017-10-02 00:00
William Audeh : Cedars-Sinai Medical CenterPrinciples of Evolutionary Biology have been applied to the problem of cancer, primarily to explain why cancer develops. This approach has focused on intrinsic mutation rates and the stochastic risk of carcinogenesis, as well as the issue of “mismatch”, in which the argument is made that cancer arises because the human genome is mismatched and maladapted to the modern environment. What has been lacking until recently, however, is the practical application of evolutionary biology to guide the therapy of cancer in a clinically meaningful way. Cancer is understood and managed by clinicians as a clinical disease, rather than what evolutionary biology more correctly identifies it to be: a diverse population of cells undergoing active micro-evolution, adapting in response to the selective pressures of therapy and the tissue micro-environment, like an invasive species. The explosion of genomic information about cancer now allows a different, biologically-enlightened strategy to guide cancer therapy, based upon recognized principles of evolutionary biology and population genetics.
This is very similar in topic to the talk I gave at Grand Rounds for Darwinian Medicine Month in February, but will be modified and updated for a non-clinical audience.

Lauren Schroeder - Skull Diversity Within the Homo Lineage
2017-10-09 00:00
Lauren Schroeder: University of Toronto Mississauga Our genus is characterized by a significant amount of morphological diversity, a phenomenon at the heart of the longstanding debate surrounding the origin and evolution of Homo. Recent fossil discoveries from Dmanisi, Georgia, Ledi-Geraru, Ethiopia, and the Cradle of Humankind in South Africa have expanded the range of morphological variation observed within our genus, leading to new questions surrounding the mosaic nature of morphological evolution. This presentation explores skull diversity within Homo, focusing on the possible evolutionary processes that may have driven such a degree of diversification and innovation.

Michael Gurven - Do Costs of Reproduction Affect Human Survival?
2017-10-16 00:00
Michael Gurven: University of California, Santa BarbaraSex differences in human mortality and health are widely documented in both low and high income countries. Usual explanations focus on differences in intrinsic senescence, lifestyle, and health-seeking behaviors. Another possibility is that costs of reproduction unique to women may alter their physical condition in adulthood relative to men. Additionally, variability in the intensity of reproductive effort may account for health-related phenotypic differences among women. The underlying logic behind these propositions assumes a simple trade-off given a limited energetic budget where investments in reproductive effort subtract from those affecting maintenance and survival. In this talk, I develop and explore these ideas by assessing sex differences in adult health and physical condition among small-scale, natural fertility populations of hunter-gatherers and horticulturalists. I then attempt to uncover the effects of reproductive intensity on women’s health among Tsimane Amerindians – an attempt rife with the usual methodological obstacles due to self-selection and the absence of randomization. I discuss implications in light of social environmental context and declining fertility worldwide.

Sarah Mathew - Peer Sanctioning and Cultural Group Selection Promotes Large-Scale Cooperation: Evidence from Kenyan Pastoralists
2017-10-23 00:00
Sarah Mathew: Arizona State UniversityExplaining why humans cooperate in sizable groups requires detailed knowledge of how people cooperate in politically uncentralized societies. I will present findings from the Turkana, a politically uncentralized population of pastoralists in Kenya, which indicate that: a) the Turkana maintain costly large-scale cooperation in warfare through peer sanctioning of free riders; and b) Turkana norms regulating punishment mitigate the second-order free rider problem and promote group-beneficial punitive behavior. Additionally, with data from 750 individuals drawn from nine clans of four neighboring ethnolinguistic groups, the Turkana, Samburu, Rendille and Borana, I will show that: a) between-group cultural variation is sufficiently high for cultural group selection to operate; and b) the scale at which cultural variation is maintained can explain the scale at which people cooperate. This suite of patterns indicates that peer sanctioning and cultural group selection in combination played a key role in enabling large-scale cooperation in humans.

Darby Saxbe - Hormones, Sleep, and Health Over the Transition to Parenthood
2017-10-30 00:00
Darby Saxbe: University of Southern CaliforniaBecoming a parent is transformative. This talk will review recent research on neuroendocrine and behavioral changes in new parents, including studies of longitudinal change and within-person linkage in testosterone, cortisol, sleep, and depression in both mothers and fathers.

Robert Kurzban - Is Moral Judgment Designed to Deter?
2017-11-06 00:00
Robert Kurzban : University of Pennsylvania Evolutionary psychologists are committed to the view that form follows function. This commitment carries an epistemic corollary: if a mechanism with a proposed function does not have the form that is required to perform that function, confidence in the proposed function should be reduced. The view that moralistic punishment – imposing costs on those who violate a moral norm – functions to deter harm requires that moralistic punishment have a number of features to implement that function. First, moralistic punishment should be desired and deployed (only) in cases in which agents intend that harm come about; without intent, harmful acts can’t be deterred. Second, the magnitude of punishment desired should relate systematically to the benefits perpetrators receive, in line with standard decision theory. Third, and related, no punishment should be desired when no harm is intended and no harm comes about; there should be no victimless norm violations. Fourth, whether and how much punishment is desired should depend only on the costs and benefits of perpetrators’ actions/inactions; how violations occur is irrelevant to deterrence. All four of these predicted features of moralistic punishment have been empirically falsified. In this talk, I will briefly review this evidence and discuss the implications.

Tamsin German - Core Intuitions about Persons Co-Exist and Interfere with Acquired Christian Beliefs about God
2017-11-13 00:00
Tamsin German: University of California, Santa BarbaraI will discuss research conducted in my lab assessing recent proposals that complex human cultural concepts such as acquired scientific knowledge and religious belief rely on the co-option of early developing psychological mechanisms for representing and reasoning about the world. I will present evidence for this idea from studies showing that a basic intuition that, for example, God is a person, co-exists and interferes with later acquired theological conceptions of God’s omniscience and omnipotence. This pattern of results mirrors those found showing the co-existence of and interference between core conceptions of the world and later acquired knowledge in the domain of science.

Anne Pisor - Extra-Community Relationships in Humans: From Tolerance to Transactions
2017-11-20 00:00
Anne Pisor : Max Planck Institute for Evolutionary AnthropologyRelative to non-human primates, humans are heavily reliant on social connections beyond the boundaries of their local communities. However, individuals vary in the extent to which they exhibit interest in extra-community relationships. How did humans come to have such pronounced tolerance toward extra-community individuals, and what are the relevant payoffs that modulate interest in extra-community relationships? To address these questions, I first identify the incentive structures favoring tolerance in inter-group encounters in the Primate order. Turning to ethnographic and ethnohistoric data, I emphasize how incentives for encounter are even more pronounced in humans, often with high payoffs to forming enduring social relationships via inter-group encounters. I then focus on the instantiations of these relationships among three populations of Bolivian horticulturalists, for whom integration to the national economy is changing the affordances of these connections. I discuss the extent to which an individual’s interest in extra-community relationships varies with her opportunities for access to market goods, experience of resource shortfalls, and perceptions of the qualities of extra-community individuals as social partners. I conclude by identifying candidate ways forward, including how we might better document the existence of extra-community relationships in the field and formulate informed hypotheses about the relevant incentive structures favoring, or disfavoring, these relationships.https://ac.els-cdn.com/S1090513816303178/1-s2.0-S1090513816303178-main.pdf?_tid=bc376a48-cda7-11e7-ba36-00000aacb361&acdnat=1511150776_c708aab11cea987e2b4481a174afcecbhttps://peerj.com/preprints/3400.pdf

Carolyn Parkinson - Neural Encoding and Cognitive Consequences of Human Social Networks
2017-11-27 00:00
Carolyn Parkinson: University of California, Los AngelesThe cognitive demands of navigating large groups comprised of many varied and enduring social bonds are thought to have significantly shaped human brain evolution. Yet, much remains to be understood about how the human brain tracks, encodes, and is influenced by the social networks in which it is embedded. The work presented in this talk integrates approaches from social psychology, cognitive neuroscience, and social network analysis in order to better understand how the structure of the social world is encoded in the human brain and the cognitive consequences of this structure.

Ara Norenzayan - The Origins of Prosocial Religions and the Emergence of Large-Scale Cooperation and Conflict
2017-12-04 00:00
Ara Norenzayan: University of British ColumbiaThe rise of large-scale cooperation and the spread of parochial-prosocial religions in the last 12 millennia are two longstanding puzzles, one of human psychology, and the other of cultural history. I present a theory, maintaining that these two developments were importantly linked and mutually energizing. It is grounded in the idea that although supernatural beliefs and practices originally arose as nonadaptive by-products of innate cognitive functions, particular cultural variants were then selected in a long-term, cultural evolutionary process. A suite of culturally evolved religious beliefs and practices characterized by increasingly potent, moralizing, supernatural agents, credible displays of faith, and other psychologically active elements conducive to social solidarity promoted large-scale cooperation with co-religionists, contributing to success in intergroup competition and conflict. In turn, prosocial religious beliefs and practices spread and aggregated as these successful groups expanded and outcompeted rival groups through high fertility rates, conversions, cultural imitation, and conquest. In doing so, these relentlessly expanding human populations have brought about the Anthropocene, dominating every ecological niche and gravely straining the planet’s entire ecosystem. Evidence for some of these hypotheses, alternative accounts, and intriguing open questions are discussed.

Julian Kapoor - Leks, Lies, and Audiotape: Dialects and Deception in a Tropical Hummingbird.
2018-01-08 00:00
Julian Kapoor: Cornell UniversityAmong animals that develop signals through social learning, dialects – shared signals among a subset of individuals within a larger population – are nearly ubiquitous. Despite the prevalence of dialects across social animal species ranging from hummingbirds to whales to humans, the functional significance of such variation remains elusive; do dialects reflect an evolutionarily adaptive process, or are they simply the result of randomly generated variation in signals? The majority of scientific attention has focused on the broad-scale patterns of regional dialects, where it is thought that the process of cultural drift is a major driver of divergence. Relatively little work, however, has sought to explain the existence of fine-scale dialects between sets of individuals within social groups. In my talk, I will explain the evolutionary mechanisms leading to microgeographic vocal dialects among a group-living species of tropical hummingbird, the little hermit. Specifically, I will address tests of the ideas that microgeographic dialects might represent 1) strategic avoidance of superior competitors, 2) the effects of spatial and temporal queuing for status within the social group, 3) the result of sexual selection for increased signal salience to receivers, or 4) the effects of deceptive mimicry. Finally, I will discuss the implications of my findings for the evolution of vocal learning in social organisms.

Katie Hinde - Mother's Milk: Building Blocks and Blueprints for Infant BioBehavioral Development
2018-01-22 00:00
Katie Hinde: Arizona State UniversityMother’s milk is more than a food full of essential nutrients and more than a medicine packed with protective immunofactors. Mother’s milk contains maternal signals- hormones- that influence infant metabolism, neurobiology, and behavior. A growing body of evidence demonstrates that hormones from the mother, ingested through milk, bind to receptors within the young. Glucocorticoids in mother’s milk have been associated with offspring temperament, behavior, and cognition in rodents, monkeys, and humans. Among monkeys, glucocorticoids in mother’s milk, predict better cognitive performance and, independent of available milk energy, predict a more Nervous, less Confident temperament in both sons and daughters. Additionally, maternal-origin glucocorticoids in milk predict offspring growth. Taken collectively, emerging results suggest that mothers with fewer somatic resources may be “programming” behaviorally cautious offspring that prioritize growth through hormonal signaling. Glucocorticoids ingested through milk may importantly contribute to the assimilation of available milk energy, development of temperament, and orchestrate, in part, the allocation tradeoffs of maternal milk energy between growth and behavior.

Steven Neuberg - Discriminating Ecologies: A Life History Approach to Stigma and Health
2018-01-29 00:00
Steven Neuberg : Arizona State UniversityHow does being discriminated against affect a person’s health, and through what mechanisms? Most research has focused on two causal pathways, highlighting how discrimination increases psychological stress and exposure to neighborhood hazards. I advance an alternative, complementary set of mechanisms through which stigma and discrimination may shape health. Grounded in evolutionary biology’s life history theory, the framework holds that discrimination alters aspects of the physical and social ecologies in which people live, such as access to tangible economic resources, unpredictable extrinsic causes of early mortality, biased sex ratios, and community social networks. These discriminating ecologies, in turn, pull for specific behaviors and physiological responses (e.g., related to risk taking, sexual activity, offspring care, fat storage) that can be viewed as active, strategic, and rational given the threats and opportunities afforded by these ecologies, but which also have downstream implications for a wide range of health outcomes. This framework generates unique hypotheses, including predictions (a) about the effects of discrimination on a large number of (often underappreciated) negative health outcomes, ranging from physical injury and sexually transmitted diseases to diseases related to obesity and drug use; and (b) about the ecological factors that mediate between stigmatization and health outcomes, and the behavioral and physiological strategies these features engage. It also suggests specific approaches to intervention, while pointing to complex ethical issues. In all, the life history framework complements more traditional perspectives by providing nuanced insights and hypotheses about the discrimination-health relationship.

Sandeep Mishra - Minding the Gap: Inequality, Socioemotional Comparisons, and Risk-Sensitivity
2018-02-05 00:00
Sandeep Mishra: University of ReginaSubstantial epidemiological evidence shows that higher levels of income inequality are associated with a wide array of negative societal-level outcomes, ranging from greater risk-taking and crime to poorer mental and physical health. However, surprisingly little research has examined individual-level consequences of inequality. Risk-sensitivity theory, developed in the field of behavioral ecology, may help to shed light on why inequality has such wide-ranging harmful effects. Risk-sensitivity theory specifically posits that that risk-taking is a product of conditions of need (i.e., disparity between one’s present and desired/goal states). In this presentation, I explore how risk-sensitivity can be applied to understanding risk-taking under conditions of inequality. I also address research suggesting that proximate-level emotional reactions to social comparisons and disparity can shed light on risk-sensitive decision-making specifically, and mental health more generally.

Joshua Ackerman - The Sick Sense: Sensory Detection of Infectious Disease
2018-02-12 00:00
Joshua Ackerman: University of MichiganFunctional psychological responses to the dangers of infectious disease first require perceiving that pathogenic threats exist. How do people detect such threats? One way is through use of conceptual knowledge from lay beliefs or direct communication, but another, perhaps more primitive, means involves use of specific sensory information. In this talk, I will review human and non-human evidence regarding detection of pathogen indicators, focusing on various domains of sensory cues. I will also consider the relevance of this evidence for our understanding of downstream consequences that occur following detection. These sensory processes and downstream outcomes are marked by biases that drive behavior in particular, often functional ways.

Matthew Zefferman - The Evolutionary Origins of PTSD and Moral Injury: Evidence from a Small Scale Society.
2018-02-26 00:00
Matthew Zefferman: Arizona State UniversityCombat veterans in western industrialized societies can develop a collection of symptoms classified as post-traumatic stress disorder (PTSD). The origins of PTSD are a mystery. Some posit that it has deep evolutionary roots as a mechanism for avoiding and responding to harm. Others posit that it is socially constructed and perhaps unique to industrialized societies. I propose, with a gene-culture co-evolutionary theory of combat stress, that both perspectives are partially right and incomplete. This theory explains additional puzzling aspects of combat stress, such as the origins of “moral injury.” I support this new theory with evidence from ethnographic research and interviews with Turkana warriors from northern Kenya.

Louise Barrett - Primates, Plasticity and (Un)predictability: A Pragmatic View of Social Evolution
2018-03-05 00:00
Louise Barrett: University of LethbridgePrimates are known for their large brains, behavioural flexibility and cognitive complexity. These, in turn, are argued to have been selected for by the complexity of the social environment. The interesting thing is that no one quite knows what social and cognitive complexity actually are, and our attempts at conceptualising primate social life are often anthropocentric and “logomorphic”. Here, using both empirical data from vervet monkeys and baboons, along with recent work in radical enactivism and embodied cognitive science, I discuss ways in which we can think about plasticity, complexity and social life in ways that do justice to evolutionary continuity, but don’t require primates and other animals to just be hairier, less talkative versions of ourselves. This in turn has implications for how we think about our own evolution, and what we talk about when we talk about “minds”.

Michele Gelfand - Tight or Loose: A Fractal Pattern of Human Difference
2018-03-12 00:00
Michele Gelfand: University of Maryland Over the past century, we have explored the solar system, split the atom, and wired the Earth, but somehow, despite all of our technical prowess, we have struggled to understand something far more important: our own cultural differences. Observing the wide variety of cultural permutations, people assumed for centuries that there were as many explanations for these permutations and rifts as there were examples of them. But what my research has uncovered is that many cultural differences reflect a simple, but often invisible distinction: The strength of social norms. Tight cultures have strong social norms and little tolerance for deviance, while loose cultures have weak social norms and are highly permissive. The tightness or looseness of social norms turns out to be a Rosetta Stone for human groups. Using field, experimental, computational, and neuroscience methods, I’ve found similar patterns of difference across nations, states, organizations, and social class. Tight-loose is also a global fault line: many of the conflicts we encounter spring from the structural stress of tight-loose tension. By unmasking culture to reveal tight-loose dynamics, we can see fresh patterns in history, illuminate some of today’s most puzzling trends and events, and see our own behavior in a new light. At a time of intense political conflict and rapid social change, this template shows us that there is indeed a method to the madness, and that moderation – not tight or loose extremes – has never been more needed.

Simine Vazire - Safer Science: The Credibility Revolution in Psychological Science
2018-04-02 00:00
Simine Vazire: University of California, DavisA fundamental part of the scientific enterprise is for each field to engage in critical self-examination to detect errors in our theories and methods, and improve them. Psychology has recently been undergoing such a self-examination. Psychological scientists arguably tackle one of the hardest phenomena to understand and predict: human behavior. Naturally, our data are noisy and our findings are often tentative. However, we are slowly building knowledge and making our theories more complete. The recent self-analysis has revealed several ways we can further improve our research practices to make our findings more sound. These new norms are gaining steam within psychology and beyond, making science stronger.
