Two-thirds of today's continental land once belonged to a single southern landmass
South America, Africa, Antarctica, Australia, Arabia and India were all pieces of Gondwana, a giant landmass that at its peak covered about a fifth of the planet. Its name comes from a forest region in India, and plants and animals across its scattered fragments still share a family resemblance.
Gondwana was assembled slowly, as stable blocks of ancient crust called cratons collided. The process began around 800 to 650 million years ago with the East African Orogeny, when India and Madagascar ran into East Africa, and it reached completion between roughly 600 and 530 million years ago as South America jammed against Africa and Australia and Antarctica were added. The mountain-building episodes behind it, grouped as the Pan-African orogeny, gathered fragments of Rodinia, a far older supercontinent. Because ancient magnetic records are scarce, geologists still do not fully understand the sequence.
Those final assembly stages overlapped with the Cambrian explosion. For a brief spell near the start of the Cambrian, the landmass Laurentia sat docked against Gondwana's western shore, forming a short-lived supercontinent called Pannotia whose existence is still disputed. At its greatest extent Gondwana was the largest piece of continental crust of the Paleozoic, spanning some 100,000,000 square kilometres, and it later merged with Laurasia to form Pangea.
The breakup came in stages. Gondwana pulled away from the northern landmass during the Triassic and began fragmenting in the Early Jurassic, about 180 million years ago. The last link to go was the Antarctic land bridge: Antarctica separated from South America and Australia between about 66 and 23 million years ago, opening the Drake and Tasmanian passages.
The Austrian scientist Eduard Suess named the continent after the Indian region of Gondwana, from the Sanskrit for forest of the Gonds. H. B. Medlicott had already used the word geologically in 1872 for a sequence of Permian and Triassic rocks. Because early definitions required a supercontinent to include Baltica, Laurentia and Siberia, some scientists prefer the longer form Gondwanaland to keep the landmass distinct from the Indian region.
Source: Gondwana
