The Cretaceous–Paleogene (K–Pg) extinction event, also known as the Cretaceous–Tertiary (K–T) extinction, was a sudden mass extinction of three-quarters of the plant and animal species on Earth, approximately 66 million years ago. The Alvarez hypothesis posits that the mass extinction of the dinosaurs during the Cretaceous–Paleogene extinction event was caused by the impact of a large asteroid on the Earth. Jesse Mason of the … Continue reading →