Science (Audio)

Humans excel at transmitting ideas, skills, and knowledge across generations, and at building on those competencies in a cumulative manner. James Rilling, Professor of Psychology at Emory University, explores how the transmission of our cumulative culture is assumed to depend on both language and mental perspective-taking, or theory of mind. If humans have specialized abilities in these domains, we must have neurobiological specializations to support them. Our research has used comparative primate neuroimaging to attempt to identify such specializations. The arcuate fasciculus is a white matter fiber tract that links Wernicke’s and Broca’s language areas. It is known to be involved in multiple, high level linguistic functions such as lexical semantics, complex syntax, and speech fluency. Using diffusion weighted imaging and tractography, we have demonstrated human specializations in the size and trajectory of the arcuate fasciculus that may partially explain human linguistic abilities. Theory of Mind depends on a set of cortical regions that belong to a neural network known as the default mode network that is functionally connected, highly active at rest, and deactivated by attention-demanding cognitive tasks. We and others have used functional neuroimaging to show that chimpanzees and other primates appear to have a default mode network that is similar to that of humans. However, the non-human primate default mode network seems to have weaker connectivity between certain key nodes, suggesting that these connections could play a role in human theory of mind specializations. Series: "CARTA - Center for Academic Research and Training in Anthropogeny" [Science] [Show ID: 41329]

The distinct biology of the human brain, scaffolded by language and culture, allows ideas to be formed, named, shared, and accumulated across generations. Dean Falk, Professor of Anthropology, Florida State University, explains how paleoneurologists study the brains of human ancestors by producing endocasts from fossilized skulls and measuring cranial capacities. Dated skulls indicate brain size more than tripled in hominins during the Stone Age that began around 3.5 million years ago, while endocasts can also preserve traces of blood vessels and convolutions, even though sulci are often fragmentary and difficult to interpret. Falk describes how sulcal patterns differ most noticeably between great apes and humans in the lateral prefrontal cortex and in the parieto-occipital association cortices, and she addresses long-running debate about whether the lunate sulcus in evolving hominins marked the anterior border of primary visual cortex as it does in living monkeys and apes. Because few fossils exist from the earlier “Botanic Age,” she outlines how comparative primatology and evolutionary developmental biology can extend the study of brain evolution by considering brain development and locomotion, including bipedalism. She applies this extended paleoneurological synthesis with special attention to auditory entrainment and complex grammatical language. Series: "CARTA - Center for Academic Research and Training in Anthropogeny" [Science] [Show ID: 41328]

Our brains are engines of imagination—an “idea organ” that has transformed both our species and the planet. Genevieve Konopka, Chair of the Department of Neurobiology in the David Geffen School of Medicine at UCLA, asks how genes drive the development of the cell types that build the human brain and give rise to cognition, and how cognitive behavior emerges from evolutionarily adapted genomic programs. Because the human brain is comprised of heterogenous cell types, she examines gene expression patterns and chromatin states within specific cell types to gain insights into brain evolution and the development of cognitive disorders. Using single cell genomics to compare human and nonhuman primate brains, her work uncovers human brain innovations, including changes in the proportions of immature oligodendrocytes in the neocortex. She recapitulates this result in vitro using stem cell derived models from humans and nonhuman primates, highlighting the intersection of cellular genomics with brain evolution and function. Series: "CARTA - Center for Academic Research and Training in Anthropogeny" [Science] [Show ID: 41298]

Humans live in a world of ideas—born in the brain, shared through language, accumulated in culture across generations, and made reality. From the first flaked stone tools to the building of shelters, from figurative and symbolic art to abstract thought, our brains are engines of imagination—an “idea organ” that has transformed both our species and the planet itself. The distinct biology of the human brain, scaffolded by language and culture, allows ideas to be formed, named, shared, and accumulated across generations. This process of cumulative culture, knowledge built upon knowledge, has propelled humans far beyond the cognitive landscapes of other large-brained animals, including our closest living and extinct relatives. This symposium explores how the human brain develops, functions, and maintains its role as the seat of ideas. We trace its story from molecules, cells, neuronal migration and circuitry, to the maternal, parental, and social influences that shape its growth, including the countless ways that brain function can be compromised at any stage of life. We examine how the uniquely human interplay of biology and culture gave rise to a brain capable of perceiving and remaking the world around us. By examining the evolutionary roots of our “idea organ,” we aim to illuminate how this singular capacity emerged—and how it continues to drive human innovation. Series: "CARTA - Center for Academic Research and Training in Anthropogeny" [Science] [Show ID: 41358]

Humans live in a world of ideas—born in the brain, shared through language, accumulated in culture across generations, and made reality. Professor Alysson Muotri, UC San Diego Departments of Pediatrics and Cellular and Molecular Medicine, examines how human brain evolution reflects the interplay between genetic innovation and environmental pressures, focusing on Neuro-oncological ventral antigen 1 (NOVA1), an evolutionarily conserved splicing regulator essential for neural development with a protein-coding substitution unique to modern humans compared with Neanderthals and Denisovans. By reintroducing the archaic NOVA1 allele into human induced pluripotent stem cells and studying cortical organoids, the work finds accelerated maturation, increased surface complexity, altered synaptic marker expression, and changes in electrophysiological properties. Muotri also analyzes long-term lead exposure using fossilized teeth from multiple hominid species spanning over two million years, revealing pervasive exposure across extinct and extant hominids. Lead exposure selectively disrupted FOXP2 expression in cortical and thalamic organoids carrying the archaic NOVA1 variant, and findings were independently validated in NOVA1 humanized mouse models with altered vocalization. Together, these results suggest gene–environment interactions may have influenced neural circuit development, social behavior, and complex language capacity. Series: "CARTA - Center for Academic Research and Training in Anthropogeny" [Science] [Show ID: 41297]

If you love seafood, you’re not alone — but every bite comes from a complex and fragile marine ecosystem. To keep our ocean ecosystems thriving and our seafood resources abundant, we need a deeper scientific understanding of how they function. Colleen Petrik, a professor of oceanography at UC San Diego's Scripps Institution of Oceanography, talks about her work studying the changing ecosystem of the ocean from fishing to coastal development. Series: "Jeffrey B. Graham Perspectives on Ocean Science Lecture Series" [Science] [Show ID: 41301]

A common model of AI suggests that there is a single measure of intelligence, often called AGI, and that AI systems are agents who can possess more or less of this intelligence. Cognitive science, in contrast, suggests that there are multiple forms of intelligence and that these intelligences trade-off against each other and have a distinctive developmental profile and evolutionary history. Exploitation, the pursuit of goals, resources and utilities, is characteristic of adult cognition. Alison Gopnik, professor of psychology and affiliate professor of philosophy at the UC Berkeley, and a member of the Berkeley AI Research Group, argues that two very different kinds of cognition characterize childhood and elderhood. Childhood is characterized by exploration. In particular, children seek out information about the world. However, forgoing reward for exploration requires support, care and teaching from others. Care and teaching are particularly characteristic of elders and the intelligence of care has a distinctive structure – it involves empowering others – giving them the resources they need to be effective. The combination of these different kinds of intelligence across the course of a life explains human success. Series: "UC Berkeley Graduate Lectures" [Humanities] [Science] [Show ID: 41068]

The extractive linear economy and policies focused on endless growth have produced unparalleled socioeconomic inequality and the climate crisis. Communities around the world are calling for new economic models that are regenerative towards people, place, and ecosystems. Ancestral ʻŌiwi (indigenous Hawaiian) economic systems were built around people's relationships and understandings of wai (water). Kamanamaikalani Beamer, Director of the Kamakakūokalani Center for Hawaiian Studies at the University of Hawaiʻi, explores the lessons that can be drawn from the Hawaiian Ancestral Circular Economy and the resurrection of peoples' ancestral relationships to love and protect water. Series: "Ethics, Religion and Public Life: Walter H. Capps Center Series" [Public Affairs] [Science] [Show ID: 41295]

Dramatic advances in ancient DNA technologies have revolutionized our understanding of the human past. As part of the CARTA symposium on Ancient DNA, the panelists answer questions about the diverse applications of archaeogenomics in shaping not only a new vision of the human past, but also in creating a greater understanding of the present and our shared human future. Series: "CARTA - Center for Academic Research and Training in Anthropogeny" [Science] [Show ID: 41202]

Genetic data is transforming the understanding of our own species and refining historical chapters at different scales around the globe. However, despite the globalization of biotechnologies to analyze the human genome, indigenous populations from the Americas and Oceania remain underrepresented in large-scale genomic studies. Andrés Moreno-Estrada, Cinvestav, discusses recent efforts to characterize the genetic profile of Indigenous Americans throughout the analysis of ancient and modern DNA, as well as their relationship within and beyond the continent, including the possibility of prehistoric contacts with Pacific Islanders. This topic poses challenges and opportunities to adequately study human diversity not only for the benefit of genetic research and science, but also for the benefit of the local communities, which are bearers of a unique evolutionary history that has been recorded in their DNA. This rapidly evolving field also raises questions about the best practices when studying the DNA of underrepresented ancestries while conducting cutting-edge science in a more equitable way. Series: "CARTA - Center for Academic Research and Training in Anthropogeny" [Science] [Show ID: 41201]

Large-scale optimization and machine learning shape modern data science, and Courtney Paquette, Ph.D., McGill University, studies how to design and analyze algorithms for large-scale optimization problems motivated by applications and data science. Paquette draws on probability, complexity theory, and convex and non-smooth optimization, and examines scaling limits of stochastic algorithms. Speaking with Saura Naderi, UC San Diego, Paquette describes an unconventional path from finance to pure mathematics and explains how persistence and comfort with uncertainty support long-term research. She highlights the challenge of building missing foundations while advancing through graduate training, and she connects that experience to the realities of doing original work. Paquette also reflects on rapid progress in machine learning and frames AI systems as tools that can be used thoughtfully. Series: "Science Like Me" [Science] [Show ID: 41119]

The human genetic history of South Asia has been shaped by its pivotal location at the crossroads of East and West Eurasia, dramatic landscapes such as the Himalayas, and longstanding socio-cultural practices like endogamy. A consequence is the diversity of East and West Eurasian genetic ancestral lineages found in South Asians today. Maanasa Raghavan, professor at the University of Chicago, explains that the increasing genome-wide data from ancient and present-day humans are providing emerging insights into the demographic processes that underlie present-day genetic diversity of South Asians and how they interface with evidence from archaeology, anthropology, linguistics, and oral histories. Human history in South Asia is also closely intertwined with the animals that humans domesticated, traded, and moved with them, offering yet another window into the dynamics of human mobility and connectivity in the past. Raghavanon's talk focuses on ancient and modern DNA insights into the origins of present-day human genetic diversity in South Asia, evolutionary history of domesticates, and broader implications for our understanding of human movements and interactions across Eurasia. Series: "CARTA - Center for Academic Research and Training in Anthropogeny" [Science] [Show ID: 41200]

Stem cell science is reshaping treatment for complex disorders of the brain and spinal cord. Researchers develop cell based therapies to replace lost dopaminergic neurons in Parkinson’s disease, fill gaps across spinal cord injuries, and calm seizure networks in refractory epilepsy by restoring the balance of inhibition and excitation. Teams test immune cell therapies against Epstein Barr virus infected B cells in multiple sclerosis and collaborate to move treatments across the blood brain barrier to reach diseased cells. Clinicians combine imaging in the operating room, surgical tools, and research on biological age and the pace of aging to understand disease and guide treatment. Patient advocates describe challenges and hopes for better options, and contemporary art reflects on perception in digital and physical worlds. Series: "Stem Cell Channel" [Health and Medicine] [Science] [Show ID: 40992]

Ancient DNA has revolutionized the study of the human past, providing unprecedented insights into ancient migrations and interactions among populations. Central Asia, due to its geographic location between Europe and Asia, has seen experienced diverse human and hominin migrations, which have been a focus of genetic, archaeological, linguistic, and historical research. Ainash Childebayeva, professor at the University of Texas at Austin, discusses recent advances in population genetics which have revealed the complex ancestry of Central Asian groups, both modern and ancient. Significant progress has also been made in understanding the role of natural selection in shaping genetic variation across the region. Childebayeva presents recent developments in our knowledge of Central Asia’s genetic history, integrating findings from both modern and ancient genomic studies. Additionally, she highlights the selective pressures that have influenced the genomes of Central Asians through time, shedding light on the dynamic interplay between admixture, adaptation, and cultural change. Series: "CARTA - Center for Academic Research and Training in Anthropogeny" [Science] [Show ID: 41199]

We’re surrounded by digital devices — from phones and tablets to streaming platforms and social media. In this excerpt, Kristy Hamilton, Assistant Professor in the Department of Communication at UCSB, shares findings on how cognitive self-esteem can change if a person is using a personal mobile device. Series: "GRIT Talks" [Science] [Show ID: 41214]

Over the past decade, archaeogenetics has analyzed more than 15,000 ancient genomes spanning 45,000 years of western Eurasian prehistory, uncovering dozens of migrations that reshaped Europe. Johannes Krause, Max Planck Institute, traces the earliest, unsuccessful attempts of modern humans to settle Europe after leaving Africa around 50,000 years ago, when they also interbred with Neandertals. Krause examines two major genetic turnovers of the Neolithic: the spread of early farmers from Anatolia about 8,000 years ago, who brought agriculture and domesticated animals and later mixed with indigenous hunter-gatherers; and the arrival of mobile herders from the Pontic steppe around 5,000 years ago, who introduced pastoralism and possibly Indo-European languages. Finally, he considers migrations triggered by the collapse of the Roman Empire, showing how large-scale mobility created the multiple ancestral strands found in modern Europeans. Series: "CARTA - Center for Academic Research and Training in Anthropogeny" [Science] [Show ID: 41198]

Dramatic advances in ancient DNA technologies have revolutionized our understanding of the human past. Since the publication of the first ancient human genomes in 2010, the field of archaeogenomics has grown at an astonishing pace, and today the genomes of more than 10,000 ancient humans have been sequenced. Kicking off this symposium are CARTA Co-Director and Salk Institute President Jerry Joyce and event co-chair Johannes Krause. Series: "CARTA - Center for Academic Research and Training in Anthropogeny" [Science] [Show ID: 41194]

How do most organisms in the natural world communicate? It's through the language of chemistry. Scripps Institution of Oceanography marine biologists Bradley Moore and Natalie Grayson explore how ocean life uses molecules as a language. Examples include a pigment that lets squid and octopus change color for camouflage, a coral and its microbial partners that produce biologically active compounds, and a chemical now in phase three human clinical trials to treat glioblastoma, an aggressive cancer of the brain. Their research has applications for new materials in biotech, and improving the food supply and human health. Series: "Jeffrey B. Graham Perspectives on Ocean Science Lecture Series" [Science] [Show ID: 41190]

How do you navigate a nonlinear, “squiggly line” career in science and public health? Dr. Katelyn Jetelina, an epidemiologist and scientific communicator, explores challenges of science communication within academia—from cultural resistance to misaligned incentives—and why so much vital research never reaches the public. Joined by Dr. John Schwartzberg, Professor Emeritus, School of Public Health, they discuss the growing opportunities for scientists both within and beyond academia, and what needs to change to better support public impact across all career paths. Series: "UC Berkeley Graduate Lectures" [Health and Medicine] [Science] [Education] [Show ID: 41067]

We’re surrounded by digital devices — from phones and tablets to streaming platforms and social media. In this excerpt, Kristy Hamilton, Assistant Professor in the Department of Communication at UCSB, shares research on how digital media shapes the way we see ourselves and the way we behave. Series: "GRIT Talks" [Science] [Show ID: 41215]