Fact
Days were shorter when dinosaurs were alive
Late Cretaceous days ran about 23 and a half hours. Growth rings in shells recorded it.
Because Earth’s rotation is gradually slowing, the day has been lengthening throughout history. Daily growth bands in fossil molluscs let researchers count days per year directly: one Cretaceous shell yielded 372 days in a year, implying a day of roughly 23.5 hours.