“If Wake and Vredenburg were correct, then those of us alive today not only are witnessing one of the rarest events in life’s history, we are also causing it.” 

Kolbert references a common theme of her book in this quote. She firmly believes that human-caused extinction is the primary mover of the Sixth Extinction. What we may not realize is that by destroying other species, we are also paving the way for our own demise.

“Today, amphibians enjoy the dubious distinction of being the world’s most endangered class of animals; it’s been calculated that the group’s extinction rate could be as much as forty-five thousand times higher than the background rate. But extinction rates among many other groups are approaching amphibian levels. It is estimated that one-third of all reef-building corals, a third of all freshwater mollusks, a third of sharks and rays, a quarter of all mammals, a fifth of all reptiles, and a sixth of all birds are headed toward oblivion.” 

Once considered the greatest survivor on the planet, amphibians have not been able to adapt to a rapid change in environment and climate, or survive the influx of invasive species and diseases that have been carried around the world by human beings. 

“On the basis of a few scattered bones, Cuvier had conceived of a whole new way of looking at life. Species died out. This was not an isolated but a widespread phenomenon.” 

Cuvier’s theory, formed via his career as a “fossilist,” was that species went extinct during certain epochs because of cataclysmic events that occurred in those moments, such as the giant meteor that wiped out the dinosaur species. This theory of catastrophism was widely mocked by many scientists at the time, but in fact, it has since been accepted as a cause of extinction.