ANOTHER Mass Extinction?! Compelling Proof of Past Mass Die-off

As far as scientists know, there have been a grand total of five mass extinctions over the last 500-million years - world-changing events during which the great majority of Earth's life was eliminated to make way for new organisms and evolutionary paths. However, for several decades, some experts have suspected that a 6th mass extinction existed among these "Big Five." Now researchers are claiming to have found extremely compelling proof of its existence.