he concluded that the contemporary extinction rate was “on the order of 10,000 times greater than the naturally occurring background rate.” This, he further observed, was “reducing biological diversity to its lowest level” since the end-Cretaceous extinction, an event, he noted, that while not the worst mass extinction in history, was “by far the most famous, because it ended the age of the dinosaurs, conferred hegemony on the mammals and ultimately, for better or worse, made possible the origin of our own species.”
