In the twentieth century, the biodiversity crisis, as it eventually came to be known, only sped up. Extinction rates are now hundreds—perhaps thousands—of times higher than the so-called background rates that applied over most of geological time. The losses extend across all continents, all oceans, and all taxa. Along with the species formally categorized as endangered, countless others are headed in that direction.
Why would you classify this as a great extinction event? How could this affect the human population?
