On an expedition to Antarctica, it’s easy to stare in awe at the gorgeous, icy landscape and forget that it hasn’t always been this way. What we see is a large continent swathed in ice and home to myriad unique animal species, not to mention a number of scientific outposts. However, our world’s southern-most continent was once very different. Let’s look back in time and see where it came from.
Antarctica’s earliest days
Once, there were few continents at all on Earth. Indeed, Alfred Wegener’s 1912 theory of continental drift surmises that a number of supercontinents shifted into each other about 1 billion to 542 million years ago, forming the enormous landmass known as Pangaea. The southern region of this land was Gondwana, which consisted of modern day South America, Australia, India, Africa and Antarctica, according to Encyclopaedia Britannica. We know this because numerous fossil records have been taken from these nations that match each other’s origins. Imagine Antarctica lying at the equator, teeming with both plant and animal life. That’s what its prehistory was like, according to the Australian Antarctic Division. Indeed, explorers found 200-300 million-year-old plant fossils from the genus Glossopteris, a now-extinct type of seed plant, on the continent, which compare to those from India, South America and Australia.
However, Gondwana was not to remain. From around 150-180 million years ago, it began to separate, seeing South America-Africa and India depart from Australia-Antarctica. About 10-40 million years later, the Atlantic Ocean was created when the former two continents split away from each other, while India and Madagascar coming away from Australia-Antarctica filled the Indian Ocean. The lands Down Under stayed together for some time after, until Australia alone began to move north quite quickly, crashing into Southeast Asia. Antarctica was finally isolated.
— Antarctic Station (@AntarcticBase)
April 22, 2015
How did it get its ice?
Though the exact story of Antarctica’s ice development is uncertain, there are some theories. It is believed that the reduction in Earth’s carbon dioxide levels, as well as changes in its orbit, caused a high degree of cooling. This, in combination with the formation of the Antarctic Circumpolar Current, formed glaciers on the landmass, which grew sizably and carved deep valleys in the landscape. This was about 34 million years ago. When the ice cooled further, it froze these shifting sheets to the rock, preserving the landscape below and covering it in a thick blanket of white. More research is needed on how the continent-sized sheets truly formed, but it makes for a fascinating discussion point on Antarctic voyages around the Peninsula.
- Exploring the past and future of Antarctica with Dr Paul Willis
- Learn about Antarctica’s regions
- Check out our daily excursions in Antarctica