Eromanga
The Eromanga region of Australia was once beneath a shallow ocean.CC

An ancient sea that once submerged the arid centre of Australia could return one day, splitting the country down the middle. The Eromanga Basin was a vast sea 100 million years ago, with sharks, turtles and plesiosaurs living together in the prehistoric land.

However, the asteroid that wiped out the dinosaurs 66 million years ago also dried up the sea and pushed its species to extinction. Just as the shallow ocean – which covered about a third of the country – disappeared, so too could it return, a scientist has said.

Danielle Clode told news.com.au: "Australia looked like an archipelago with land down the east and west. The sea was dominated by marine reptiles, plesiosaurs, ichthyosaurs, Loch Ness monster-type creatures, things that look like dolphins, only much bigger. Australia is an old country and it's been the same for a long time, but it has changed dramatically. We need to think about what climate is suited to us. These animals were sensitive to climactic conditions — and so are we."

Plesiosaur
Plesiosaurs once lived in the Eromanga Sea

At the time of the Eromanga Sea, Australia had a cool and wet climate and parts of the continent would have had a polar winter, with the south having sea-ice that would melt in the spring. In the north, the water was warmer and ice would not have been able to form. On land, towering conifer forests covered much of the country, with smaller plants creating an understory.

Fast forward 110 million years and experts say the Eromanga could return as a result of climate change, an asteroid or another ice age – and that this could happen any time from thousands to many millions of years in the future. Whether any human beings will be there to see it is another question.