The Evolutionary Epic: From Single Cells to Dinosaurs

CrashCourse

This episode of Crash Course Big History provides a dynamic and comprehensive overview of the evolutionary epic of life on Earth. Hosted by John Green, Hank Green, and Emily Graslie, the video traverses 3.8 billion years of history, explaining the mechanisms of evolution by natural selection and the dramatic history of life's development. It clarifies the scientific definition of "theory," distinguishes random variation from non-random selection, and highlights the pivotal role of mass extinctions in shaping biodiversity. The narrative moves from single-celled organisms through the Cambrian explosion, the colonization of land by plants and animals, and the reign of dinosaurs, culminating in the rise of mammals.