What Really Killed the Dinosaurs? | Dinosaurs Inside and Out | Ep. 4

65 million years ago, the most successful animals in the history of life on Earth vanished from the fossil record. The popular explanation is an asteroid impact. But many scientists are convinced that is only part of the story, and the search for a fuller answer has taken researchers to the ocean floor, the bottom of ancient amber deposits, and the far reaches of the solar system. Off the coast of Mexico, geologist Harold Sigurdsson leads a deep-sea drilling expedition to the site of the asteroid impact, buried beneath a mile of ocean sediment. He is looking for evidence that the asteroid struck an unusually sulfur-rich seabed, releasing clouds of acid rain far more lethal than the impact alone. Meanwhile, paleontologist Keith Rigby has been studying the fossil record in Montana and finds something troubling: the dinosaurs were already in decline long before the asteroid hit, with extinctions unfolding gradually across tens of thousands of years. Rigby's alternative theory begins with ancient air. Working with geochemist Gary Landis, the team extracts bubbles of atmosphere trapped inside Cretaceous amber, some of the only samples of air that dinosaurs ever breathed. The results reveal that oxygen levels during the age of dinosaurs were nearly 35%, compared to 21% today. As tectonic activity slowed, carbon dioxide output fell, plant life diminished, and oxygen levels dropped, the dinosaurs, lacking the efficient respiratory systems of mammals, may have slowly suffocated over millions of years. The episode closes with a different question: could it happen again? At Kitt Peak Observatory in Arizona, the Space Watch project scans the skies for near-Earth asteroids, finding roughly three new candidates per month. At Wild Life, we are dedicated to bringing you the most breathtaking wildlife and nature documentaries from every corner of the globe. From the awe-inspiring majesty of predators in the wild to the intricate beauty of delicate ecosystems, our documentary films invite you on a thrilling adventure to the planet's most fascinating destinations. Whether you're a passionate nature lover, a curious traveller, or a wildlife enthusiast, there’s something here for everyone. With fresh content added regularly, you'll always discover new stories that spark your wanderlust and deepen your appreciation for the wild. Join our vibrant community of explorers and let your journey begin! Subscribe now and embark on an unforgettable exploration of the world’s enchanting landscapes and extraordinary creatures! #FullFreeMovies #FreeDocumentary #Wildlife #NaturalHistory #PlanetEarth