We could be on the brink of a mass extinction — the Earth’s sixth — according to a paper published last year in the journal Nature. First author Anthony Barnosky, an integrative biologist at the University of California at Berkeley, says Earth has experienced five mass extinctions during the past 540 million years, and another extinction could be around the corner. During each of the five previous events, three-quarters or more of the world’s animal species died out. One of the mass extinctions — which occurred 65 million years ago — ended the dinosaurs.
Some say, however, that this isn’t much cause for alarm. Species have always come and gone over long periods of time; and given the five mass extinctions we’ve already had, it’s a natural event. But will this sixth one be a “different animal”?