The Nature & Nurture Podcast

Dr. Webb Keane is the George Herbert Mead Distinguished University Professor in the Department of Anthropology at the University of Michigan. He is an expert in the anthropology of religion and ethics; semiotics and language; material culture; gifts, commodities, and money; and media. He is the author of Animals, Robots, Gods: Adventures in the Moral Imagination. In this episode we discuss Webb’s central argument that ethical dilemmas posed by interactions with non-humans and near-humans, including animals and AI, share common themes reflected in narrative and mythology cross-culturally. We discuss these findings in relation to cultural anthropology, evolutionary psychology, AI and large language models, and video games. 00:23 Exploring the Book's Themes 01:04 AI and Moral Imagination 04:51 Religious Language and AI 08:29 Human-AI Interaction 17:32 Moral Dimensions of Hunting 22:01 Animal Emotions and Morality 31:10 AI as a Moral Entity 34:45 The Fear of AI and Human Intentions 35:38 The Moral Implications of AI Decisions 38:34 Ethics and Social Interaction 41:04 Language and Perception 47:19 Cultural Differences in Language 52:48 The Intersection of Technology and Identity 59:46 Mythology and Technology in Popular Culture

Dr. Bailey is a psychologist, behavioral geneticist, and Professor at Northwestern University specializing in the etiology of sexual orientation, sexual preferences and paraphilias, and gender diversity. In this episode, we discuss the history of transexualism in clinical psychology and its relation to modern transgender identifying people, the science and ethics of gender affirming care in adults and children, and the different manifestations of gender dysphoria across children, men, women, and comorbidity with autogynephilia. We also discuss the heritability of sexual orientation, the role of prenatal hormones in determining sexual orientation, gender identity, and psychological gender differences, and arousal patterns. Lastly, we discuss the politics of sexology as a field, and how to conduct effective and impartial research on politically charged topics such as researching gender dysphoria, its causes, and evidence bases.

Dr. Holly Bowen is an Assistant Professor of Psychology at Southern Methodist University. Dr. Bowen’s research focuses on how affective states, specifically emotion and motivation, influence how we form memories and remember past experiences. She is also interested in how the links between emotion, motivation and memory are impacted by age-related cognitive changes, using multiple methods including behavioral paradigms, computational modeling, and neuroimaging with event-related potentials (ERP) and functional magnetic resonance imaging (fMRI). In this episode Holly and I discuss emotion and motivation’s impact on memory encoding and consolidation, the differences between emotional valence verses arousal and their neurophysiology, and their connections to the reward system, the amygdala, and the hippocampus. We talk about dual-systems models of reward processing, cognitive control, and decision-making, the role of dopamine in facilitating learning and memory, the role of norepinephrine and cortisol in threat processing and fear conditioning, and paradoxes in how brain activity and behavior changes with age. Lastly, we discuss the negativity bias in memory, the positivity bias in nostalgia, and how socioemotional selectivity and changes in emotion regulation skills may explain age-related changes in these phenomena.

Dr. Lars Chittka is a Professor of Sensory and Behavioral Ecology and the founder of the Research Center for Psychology at Queen Mary University of London. He directs the Bee Sensory and Behavioral Ecology Lab, and is the author of The Mind of a Bee. In this episode, we discuss the results of decades of research on intelligence in bees and other insects. This includes findings of numerical and spatial cognition, memory, perception, and personality. Lars describes differences and similarities between bumblebees, wasps, and honeybees, why honeybees produce so much honey and die after stinging and mating, and more. We also discuss the evidence for bees having emotions, feeling, and consciousness, and efforts for the preservation and ethical handling of bees.

Dr. Kevin Mitchell is an Associate Professor of Genetics and Neuroscience at Trinity College Dublin. He's the author of Innate: How the Wiring of Our Brains Shapes Who We Are, and Free Agents: How Evolution Gave Us Free Will. In this episode, we talk about Free Agents and the question of free will. We discuss what we mean by freedom, how living organisms have inherent biological constraints which actually define ourselves as causal agents. We also discuss the common scientific view of reductionist determinism and its limitations, and how causal agents use the inherent indeterminacy and forward motion of time in our universe as "causal slack" to make predictions and control their behavior in a meaningful way. We talk about the role entropy plays in life and computation, how free will grows as computational and cognitive complexity grows, and how these realities should define our ethical and legal conceptions of moral responsibility. Lastly, we talk about how individual differences in genes, environment, and brain development shape our personalities and constrain us in some ways, but also offer opportunities for unique identity, character development, meaning, and purpose.

Dr. Jennifer Silvers is an Associate Professor of Psychology and the Bernice Wenzel and Wendell Jeffrey Term Endowed Chair in Developmental Neuroscience at UCLA, where she runs the Social Affective Neuroscience and Development Lab. She is an expert in adolescent brain, cognitive, and emotional development, particularly in the development of emotion regulation strategies. In this episode, we talk about Jen’s background in developmental neuroscience, the use and limitations of animal models for understanding human brain development, and how adolescence is a particularly exciting window of brain development both due to puberty and other social and environmental changes. We talk about the role of stress and adversity influencing brain development, temperamental factors in emotion processing, emotion regulation as a learned skill, and how puberty interacts with all of these processes. We then discuss relatively recent effects on social and emotional development, such as the COVID-19 pandemic, social media use, and the influence of online dating apps in young adults’ sexual development. Lastly, we talk about other windows of rapid change influencing socioemotional processing, such as pregnancy, and future directions linking our shared interests in hormones and brain development in large-scale consortium-based studies.

Dr. James Roney is a Professor of Psychological & Brain Sciences at the University of California, Santa Barbara, where he runs the Human Behavioral Endocrinology Lab. In this episode we talk about the proximate and ultimate evolutionary explanations of different sex hormones’ roles in coordinating motivated behavior, such as testosterone’s influence on aggression and sex drive, and ovarian hormones’ influence on sex and food drive. We discuss how testosterone leads to sex differentiation in the brain and body both prenatally and during puberty; threshold effects, rather than continuous relationships, between testosterone and motivation; the opposite effects of estradiol and progesterone on women’s sex and food motivation across the menstrual cycle. We also discuss genetic differences in the receptors to different hormones, their interactions with other hormones, and how these subtle differences may predict traits ranging from morphology to sexuality. Lastly, we discuss Jim’s recent research using daily diaries and saliva hormones to test whether daily hormonal fluctuations influence sex drive and other motivated behavior, how smell and pheromones influence attraction in males and females, and how sex hormones influence reward processing in the brain, particularly during puberty. Timestamps: 0:00:51 Hormones act as coordinators in the body 0:02:06 Example of testosterone's input and output relationships 0:05:41 Importance of understanding the inputs and outputs of hormones 0:07:43 Conservation of hormone functions from non-human species to humans 0:09:35 The role of hormones in motivated behaviors 0:11:19 Time lag between stimulus event and hormone response 0:15:19 Evolutionary theories and mating behavior tied to sex hormones 0:18:23 Evolution and psychological functions of testosterone and oxytocin 0:20:08 Understanding hormone inputs and context for coordinated effects 0:21:58 Oxytocin paradox and effects on maternal aggression 0:23:33 Confounding effects of multiple signals on hormone outputs 0:25:14 Individual variability and receptor sensitivity to testosterone 0:26:47 Genetic polymorphism and developmental calibrators of individual differences 0:28:10 Prenatal testosterone and sexual orientation 0:38:21 Threshold effects of testosterone 0:41:06 Continuous relationship between estradiol, progesterone, sex drive, and food drive in women 0:53:01 Testosterone's effect on reward may be more generalized than estradiol and progesterone 0:54:47 Estradiol may affect satiety mechanisms, not just reward systems. 0:56:56 Theoretical framework for risk taking and impulsivity. 0:58:26 Research on anxiety and depression in females during puberty. 0:59:58 Effects of testosterone on motivation and individual differences 1:08:08 Study on concealed ovulatory timing, pheromones, and scent attractiveness during ovulation