History › Complex life › Age of dinosaurs
Supercontinent Pangaea
assembled c. 335 million years ago; split apart from c. 200 million· Event· Universe & Earth
Well documentedSolid records, physical evidence or scientific consensus.
Nearly all of Earth's land joined into one supercontinent, surrounded by a single world ocean called Panthalassa.
See it on the History map →What happened
Continents ride on moving plates, drifting a few centimeters a year. By about 335 million years ago they had collided into Pangaea ('all land'), pushing up mountains such as the Appalachians. Its huge interior was largely dry. From about 200 million years ago it split apart, opening the Atlantic Ocean, and the pieces drifted toward today's map. The Curious Science map covers plate tectonics.
Why it matters
Joined land let animals spread worldwide; the breakup isolated them, which is one reason Australia's animals differ so much from Africa's.
How we know
Matching coastlines, rocks and fossils across oceans, such as the reptile Mesosaurus in Brazil and South Africa; seafloor magnetic stripes; GPS measuring plate motion. Alfred Wegener proposed drift in 1912; it won acceptance in the 1960s.
Still debated
How earlier supercontinents formed and broke up, and exactly how the next one may form in some 200–250 million years, are open questions.
Connections (2)
▸Supercontinent Pangaea was the world of the early Age of dinosaursWell documented
The connection
When dinosaurs appeared about 230 million years ago, nearly all land was joined in Pangaea. With no oceans to cross, early dinosaurs spread across the supercontinent. As Pangaea broke apart, separated dinosaur groups evolved in different directions, producing the varied types of the Jurassic and Cretaceous.
When and how
Across Pangaea in the Triassic Period, about 230–200 million years ago; the earliest fossils come from Argentina and Brazil.
How we know
Similar early dinosaur fossils turn up on continents now far apart, such as South America, Africa and India.
Debates and open questions
How much Pangaea's hot, dry interior limited where early dinosaurs could live is debated.
▸Permian extinction ('the Great Dying') struck life across Supercontinent PangaeaWell documented
The connection
The Great Dying struck while nearly all land was joined in Pangaea. With a single landmass and one world ocean, the warming, acidifying seas and loss of oxygen reached almost everywhere, possibly leaving few refuges. Life across Pangaea collapsed, on land and at sea.
When and how
Across the supercontinent and its surrounding ocean, about 252 million years ago.
How we know
Rock layers in China, Russia, South Africa and Antarctica, all once part of Pangaea, record the same abrupt extinction.
Debates and open questions
Whether Pangaea's single-block shape made the extinction worse, by limiting refuges or slowing ocean circulation, is debated.