The Journey of South America Through 300 Million Years
May 13, 2026
South America has not always sat where it does today. Over the past 300 million years it has been part of a supercontinent, joined to Africa, isolated in its own ocean, and gradually drifted to its current position. Each stage of this journey shaped the continent's geography, climate, and life.
300 Million Years Ago: Deep Inside Gondwana
Three hundred million years ago, during the Carboniferous period, South America was firmly part of Gondwana. It sat south of the equator, connected to Africa on its eastern side, Antarctica on its south, and with North America attached via a narrow connection through what is now Central America.
The climate was cold at this time. Evidence of glaciation found in Brazil, Argentina, and Uruguay confirms that parts of South America were covered by ice sheets, a dramatic contrast to the tropical forests that cover much of the continent today.
200 Million Years Ago: Pangea Begins to Break
By 200 million years ago, Pangea was starting to break up. South America remained joined to Africa but the North Atlantic was beginning to open, slowly separating North America from Europe and Africa. South America and Africa still formed a single continuous landmass.
The climate of South America at this time was shifting. The interior was increasingly arid as Pangea fragmented, with early dinosaurs crossing freely between South America, Africa, and North America before the Atlantic completed its opening.
130 Million Years Ago: The Atlantic Opens
Around 130 million years ago, rifting began to separate South America from Africa, starting in the south and slowly propagating northward. A narrow seaway formed first, eventually growing into the South Atlantic Ocean.
As South America became isolated, its fauna began to evolve independently. The continent developed a unique set of animals including giant ground sloths, armadillos, and the ancestors of modern South American mammals.
The opening of the South Atlantic was one of the most significant geological events of the Cretaceous. It took tens of millions of years for the seaway to fully develop into an ocean.
3 Million Years Ago: The Americas Unite
For most of the past 130 million years, South America was a true island continent, isolated from North America by the gap that is now Central America. Around 3 million years ago, the Isthmus of Panama rose from the sea and connected the two continents.
This Great American Biotic Interchange allowed animals to cross between North and South America. North American species like deer, horses, and big cats moved south, while South American species like ground sloths and opossums moved north.
Frequently Asked Questions
Was South America always in the same hemisphere as today?
South America has always been in the southern hemisphere, but it was further south during Gondwana times, with parts covered by glaciers, unlike the tropical continent of today.
When did the Amazon rainforest develop?
The Amazon rainforest in its modern form developed relatively recently, expanding significantly after the Andes rose and created the wet climate conditions of the Amazon basin.
Is South America still moving?
Yes. South America moves westward away from Africa at roughly 3 centimeters per year as the South Atlantic continues to widen.