Science (Video)

UCLA’s Avishek Adhikari, PhD, presents new research on the role of GABAergic neurons in the brain’s periaqueductal gray (PAG) region. Previously studied for their involvement in fear and defensive behaviors, these neurons were found to promote food-seeking behavior when activated—even in fully fed mice. Using calcium imaging and optogenetics, Adhikari’s team discovered that these neurons are active during food approach but suppressed during eating. The effect is stronger for high-value foods like chocolate or crickets and depends on the mouse’s prior experience with that food. A key finding is that these neurons influence behavior through a specific projection to the zona incerta, a subthalamic region. Rather than signaling hunger, this pathway appears to drive food seeking based on reward value, highlighting a new motivational circuit in the brain. Series: "Stem Cell Channel" [Health and Medicine] [Science] [Show ID: 40444]

The land we now call Scripps Oceanography has been home to the Kumeyaay people for thousands of years. A history of encroachment, colonization and displacement from coastal lands has challenged Kumeyaay ocean traditions and practices. Today, Kumeyaay-Iipay-Tipay people are actively revitalizing Indigenous ocean culture. As part of Perspectives on Ocean Science Lecture Series, Stan Rodriguez and Priscilla Ortiz Sawah of the Iipay Nation of Santa Ysabel, and Andrew James Pittman of the Los Coyotes Band and Cupeño Indians, talk about the history of the Kumeyaay culture in the region. Through community efforts, they are rebuilding traditional ha kwaiyo (tule boats), harvesting ha shupill (grunion) and teaching language about the ocean (ha silowik). These intergenerational practices embody Indigenous resilience, resistance and revival — nurturing and evolving Indigenous ocean knowledge, culture and traditions. Series: "Jeffrey B. Graham Perspectives on Ocean Science Lecture Series" [Humanities] [Science] [Show ID: 40596]

It's time for a new narrative for the ocean, one that reflects current scientific knowledge and acknowledges innovative new partnerships and solutions that center the ocean in our future. In this program, Jane Lubchenco, Professor of Marine Biology at Oregon State University and with expertise in the ocean, climate change, and interactions between the environment and human well-being, talks about the two current dominant narratives for the ocean are anchored in the past. The older one considers the ocean to be so vast, bountiful, and resilient that it is simply too big to fail. This first narrative drives pollution and over-exploitation of resources. A second, more recent narrative is that the ocean is now so depleted, polluted, and disrupted, and the drivers of those outcomes are so powerful and complex, that the ocean is simply too big to fix. A third, new narrative is emerging, based on scientific findings, existing solutions, and innovative partnerships and policies. This new narrative acknowledges that the ocean is central to a safe, clean, healthy, just, and prosperous future. This new narrative tells us that the ocean is neither too big to fail, nor is it too big to fix. But it is too important and too central to our future to ignore. Series: "UC Berkeley Graduate Lectures" [Public Affairs] [Science] [Show ID: 40427]

Three major global challenges – climate change, loss of biodiversity and its benefits, and inequality and inequity among people – are typically tackled within three separate silos. However, scientific knowledge tells us that the three are inextricably linked. If the problems are not considered together, solutions to one may undermine solutions to the others. Moreover, more holistic, integrated solutions can deliver multiple co-benefits. Success requires integrated solutions. Jane Lubchenco, Professor of Marine Biology at Oregon State University, talks about the historically ambitious, innovative policies implemented by the Biden-Harris Administration to achieve this integration. Lubchenco is a marine ecologist with expertise in the ocean, climate change, and interactions between the environment and human well-being. From 2021-2025, she served as Deputy Director for Climate and Environment in the White House Office of Science and Technology Policy. Series: "UC Berkeley Graduate Lectures" [Public Affairs] [Science] [Show ID: 40426]

The human body has traits that evolved at different times, from 1.5 billion to 2 million years ago, each bringing health benefits and risks. Multicellularity enabled organs and cancer. The immune system defends us but can cause inflammation. Breastfeeding supports infant health but relates to breast cancer risk. Menstruation and invasive placentas improved reproduction but led to pain and cancer risks. Human-specific traits like bipedalism and aging brought new issues like back pain and childbirth problems. Hair loss and sweat glands helped us stay cool but increased skin cancer risk. Our hunter-gatherer past shaped our microbiome and health, but also made us prone to modern diseases from lifestyle changes. Series: "CARTA - Center for Academic Research and Training in Anthropogeny" [Humanities] [Science] [Show ID: 40702]

Humans have long been exposed to three main types of smoke: from early domestic fires, modern wildfires, and more recently, tobacco and fossil fuel pollution. All release tiny particles from partly burned plants, containing harmful chemicals like nitrogen oxides and carcinogens. These particles raise risks for lung cancer, dementia, and even childhood obesity. Studies show that air pollution can disrupt brain chemistry, increase Alzheimer’s-related proteins, and activate stress-related genes (NFkB, Nrf2). A new drug (GSM-15606) shows promise in reducing brain damage from pollution in mice. People with the ApoE4 gene may be more vulnerable, while the ApoE3 gene, possibly evolved 200,000 years ago, may offer some protection. Series: "CARTA - Center for Academic Research and Training in Anthropogeny" [Humanities] [Science] [Show ID: 40700]

The human gut microbiome is tightly linked our health. Our analyses of diverse human populations from around the globe, ranging from hunter-gatherer to industrialized, show that the gut microbiome is profoundly influenced by lifestyle. With a large collaborative team, we conducted deep metagenomic sequencing of the gut microbiomes of Tsimane horticulturalists from Bolivia and compared them to those of Hadza hunter-gatherers from Tanzania. We are also investigating whether diet and microbial therapies can address deficiencies in the industrialized gut community. Molecular mechanisms of host-microbial interaction are pursued using an array of technologies and experimental approaches including gnotobiotic and conventional mouse models, quantitative imaging, and a metabolomics pipeline focused on investigating microbiota-dependent metabolites. Series: "CARTA - Center for Academic Research and Training in Anthropogeny" [Humanities] [Science] [Show ID: 40698]

The essence of Being Human is the practice of Biocultural Reproduction (BCR). BCR is defined as the set of marriage and kinship based rules for extra-maternal cooperation in the production, feeding, and care of offspring. Human evolution theory needs to explain how people successfully combined a vastly extended period of offspring dependency and delayed reproduction with helpless newborns — with large heads and much body fat (even with problems giving birth) -- a short duration of breast-feeding, an adolescent growth spurt, and vigorous post-menopause valuable grandmothers. Are these characteristics a package or a mosaic? Series: "CARTA - Center for Academic Research and Training in Anthropogeny" [Humanities] [Science] [Show ID: 40697]

Musculoskeletal disorders are one of the most important challenges of modern medicine worldwide. They are often attributed to maladaptations of our body to our peculiar form of locomotion, upright bipedalism. This lecture will explore the evolutionary origin of major musculoskeletal disorders such as back problems and hip joint osteoarthritis. I will show that these problems represent a relatively recent phenomenon, occurring only during the last few decades, and thus are unrelated to our skeletal adaptations. Series: "CARTA - Center for Academic Research and Training in Anthropogeny" [Humanities] [Science] [Show ID: 40696]

Phenotypic variation within the skeleton has biological, behavioral, and biomedical functional implications for individuals and species. Thus, it is critical to understand how genomic, environmental, and mediating regulatory factors combine and interact to drive skeletal trait development and evolution. One way to do this is by studying skeletal diseases that disrupt skeletal function — like osteoarthritis (OA) which is a chronic disorder characterized by the degradation of cartilage and underlying bone in joints and can lead to severe pain and mobility limitations. This talk will discuss what is known about OA in humans and other primates, as well as recent advances that are further informing these topics. Series: "CARTA - Center for Academic Research and Training in Anthropogeny" [Humanities] [Science] [Show ID: 40695]