Humanity Almost Went Extinct... And It Will Happen Again | Science for Sleep скачать в хорошем качестве

Humanity Almost Went Extinct... And It Will Happen Again | Science for Sleep

Welcome to Night Science! Seventy four thousand years ago, the largest volcanic eruption in two million years ripped open the island of Sumatra. The Toba supervolcano ejected nearly three thousand cubic kilometers of ash and rock into the atmosphere, triggering a volcanic winter that lasted years and dropped global temperatures by as much as five degrees. The sky went dark. Ecosystems collapsed. And the human species, already living in small scattered bands across Africa, was pushed to the edge of extinction. Genetic evidence hidden in the DNA of every person alive today reveals a population bottleneck so severe that the entire human species may have been reduced to as few as one thousand to ten thousand breeding individuals. Some researchers believe the number was even lower. A twenty twenty three study suggested that human ancestors once numbered just one thousand two hundred eighty breeding individuals for over one hundred thousand years during an even older crisis nearly a million years ago. In this documentary, we trace the full story of how humanity nearly vanished. From the mechanics of the Toba supereruption and the volcanic winter it caused, to the archaeological evidence of human survival at sites in Ethiopia and South Africa, to the genetic signatures of the bottleneck written into mitochondrial DNA and the nuclear genome, to the fierce scientific debate over what actually caused the crash and how our ancestors fought their way back. We explore the concept of minimum viable population, the founder effect, the role of Mitochondrial Eve, the Out of Africa migration, and the astonishing possibility that the crisis that nearly destroyed us may have been the crucible that forged the adaptive intelligence that defines our species. This is a story about survival at the most fundamental level. About a species that held on when every calculation said the end had come. About the thread that connected a few thousand ancient survivors to the eight billion people alive today. If you enjoy deep investigations into human evolution, ancient history, and the science behind our origins, please like and subscribe. Your support makes these detailed stories possible.