National Geographic Dinosaurs of Gondwana & Laurasia Map: (folded from the Archives)

When dinosaurs emerged some 230 million years ago, Earth was ripe for a takeover. The massive Permian extinction had wiped out many potential competitors, and continental drift had created a supercontinent, Pangaea, that stretched from pole to pole. Over many millions of years, dinosaurs proliferated, adapting to every terrestrial environment. More than 550 species have been identified, and scientists estimate that more than a thousand others are yet to be discovered. Gradually, Pangaea separated into the great landmasses of Gondwana in the south and Laurasia in the north, dividing dinosaurs into two main populations that evolved mostly in isolation from one another until they met their end 65 million years ago.