Dinosaur extinction made mammals more active in day: Study
Ancient mammals started becoming more active during the daytime around 65.8 million years ago, 200,000 years after dinosaurs went extinct, a UK-based study has inferred from genetic data of 2,000 present-day mammals. Gorillas were probably among the first to come out of the dark in dinosaurs' absence, however, a transition from nocturnal lifestyle would've taken millions of years for others.