145 – 66 million years ago

The Cretaceous

The longest of the three Mesozoic periods, the Cretaceous saw flowering plants spread across the planet and dinosaurs reach their peak diversity — just before the end.

Apex predators

Tyrannosaurus rex dominated North America, while Spinosaurus patrolled the river systems of North Africa. Smaller dromaeosaurs like Velociraptor and Deinonychushunted in coordinated groups.

The K-Pg extinction

66 million years ago, an asteroid roughly 10 km wide struck the Yucatán Peninsula. The impact, combined with massive volcanic activity in India's Deccan Traps, ended the reign of the non-avian dinosaurs. Their descendants — birds — survived.