“Microbes can come and wipe us out. It can happen fast. Avian virus or mad cow disease, you name it. … Or a cataclysmic volcanic eruption which would darken the skies for 10 years … Trilobites died out, dinosaurs died out. Life on our planet has been a constant series of cataclysmic events, and we are more suitable for extinction than a trilobite or a reptile. So we will vanish.”