For their first 100 million years on planet Earth, our mammal ancestors relied on the cover of darkness to escape their dinosaur predators and competitors. Only after the meteor-induced mass extinction of dinosaurs 66 million years ago could these nocturnal mammals explore the many wondrous opportunities available in the light of day. Fast forward to the present, and the honeymoon in the sun may be over for mammals. They’re increasingly returning to the protection of night to avoid the Earth’s current terrifying super-predator: Homo sapiens.