Topic: extinction

Steve Brusatte discusses the dinosaurs that survived the end-Cretaceous asteroid impact: birds. The episode follows fossil evidence for feathered dinosaurs and the emergence of avian traits, then considers how surviving bird lineages diversified after the extinction. Publisher illustrations connect fossils, anatomy and evolutionary relationships.

Sara Pruss discusses archaeocyath sponges, the first multicellular reef builders, and their relationship to diversification during the Cambrian. The episode traces successive reef-building groups through the geological record and asks why reefs repeatedly emerge despite environmental disruption and extinction.

In most animals including in humans, emotions occur together with changes in the body, such as variations in breathing or heart rate, sweaty palms, or facial expressions. It has been suggested that this interoceptive information acts as a feedback signal to the brain, enabling adaptive modulation of emotions that is essential for survival. As such, fear, one of our basic emotions, must be kept in a functional balance to minimize risk-taking while allowing for the pursuit of essential needs. However, the neural mechanisms underlying this adaptive modulation of fear remain poorly understood. In