Climate worldwide has been changing forever. During Gondwana's stint as the southerly supercontinent, the planet was much warmer than it was today — there was no Antarctic ice sheet, and dinosaurs still roamed the Earth. By this time, it was the Jurassic Period, and much of Gondwana was covered with lush rainforest. The great supercontinent was still under strain, however. Between about 170 million and 180 million years ago, Gondwana began its own split, with Africa and South America breaking apart from the other half of Gondwana. About 140 million years ago, South America and Africa split, opening up the South Atlantic Ocean between them. Meanwhile, on the eastern half of the once-supercontinent, Madagascar made a break from India and both moved away from Australia and Antarctica. Australia and Antarctica clung together longer; in fact, Antarctica and Australia didn't make their final split until about 45 million years ago. At that point, Antarctica started to freeze over as Earth's climate cooled, while Australia drifted northward. (Today, the Australian continent still moves north at a rate of about 1.2 inches (3 centimeters) a year.)
