CARTA - Anthropogeny (Audio)

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: 41359]

Human brain expansion is often discussed in terms of the genetic and molecular innovations that drove uniquely human cognitive abilities. Yet evolution is fundamentally a process of tradeoffs. Disproportionate expansion of forebrain structures increases the demands placed on long-range connectivity, metabolism, and cellular maintenance, imposing costs that scale with brain size. Alex Pollen, associate professor of neurology at UC San Francisco, discusses using stem-cell-derived brain organoids to investigate the development of human-specific connectivity differences in dopaminergic neurons and to test whether these cells deploy compensatory mechanisms to cope with the metabolic and structural demands of large brains. His research findings support a model in which human brain evolution involves not only mechanisms driving greater computational capacity, but also the emergence of cellular adaptations that mitigate the costs of large, highly connected brains. Series: "CARTA - Center for Academic Research and Training in Anthropogeny" [Science] [Show ID: 41357]

From stone tools and shelters to symbolic art and abstract thought, human history is shaped by a brain built to form and share ideas. Joseph Paradiso, Professor in Media Arts and Sciences at the MIT Media Lab, explores what comes next after the early visions of ubiquitous computing have largely arrived in today’s Internet of Things world, where low-power sensors and interfaces are embedded in smart devices across our environments and connect seamlessly to widespread networking infrastructure. He asks how this information connects to people, and how perception, cognition, and identity might expand beyond our corporeal confines. Drawing on recent projects from his Responsive Environments research group, he examines sensing at multiple scales in the physical world, including wearables, smart buildings, connected landscapes, and space missions, and the different ways sensed or inferred information can connect to people. Examples include smart buildings as “prosthetic” extensions of their inhabitants, manifesting sensed or inferred phenomena in virtual analog environments, and interfaces modulated by user attention and focus or augmented by real-time AI. Series: "CARTA - Center for Academic Research and Training in Anthropogeny" [Science] [Show ID: 41327]

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]

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. 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]

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]

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]