Newly-discovered fossils have revealed something stunning to the scientific world: that some of the first animals to walk on land lived in Antarctica. Scientists unearthed the fossils of prehistoric Devonian Period amphibians at a site called Waterloo Farm in Grahamstown, South Africa. Hundreds of millions of years ago, Waterloo Farm would have been in the Antarctic circle.
Devonian tetrapods are believed to be the earliest known four-legged vertebrates, making them the ancestors of all vertebrates. The new species, named Tutusius umlambo and Umzantsia amazana, pre-date the next earliest African tetrapod fossils by some 70 million years. The paleontologists, working with the South African Center of Excellence in Palaeosciences, recently published their findings in the journal Science.
The environment where the fossils were unearthed was the real surprise. Devonian tetrapod fossils are found practically everywhere in the world, with most fossils discovered in present day North America, Greenland, and Europe. However, the fossils of both Tutusius and Umzantsia were found to have come from the southernmost part of ancient supercontinent Gondwana, which became Africa, South America, Australia, Antarctica, and India in the present day.
Scientists trace the original locations of ancient fossils by mapping the movement of continents over millions of years. Dr. Robert Gess, the lead author of the study, said, “Whereas all previously found Devonian tetrapods came from localities which were in tropical regions during the Devonian, these specimens lived within the Antarctic circle.” While Waterloo Farm wasn’t frozen back in the ancient Devonian period (plant fossils show that forests grew nearby), it still faced nights that lasted for weeks in the dead of winter.
The researchers built a picture of the animals from just a few fossilized bones. They said in the published article, “Alive, they would have resembled a cross between a crocodile and a fish, with a crocodile-like head, stubby legs, and a tail with a fish-like fin.” The Tutusius species was estimated to be about 3 feet long. Umzantsia measured about 2.3 feet long.
South African fossils offer new insight on how life started on land. It was previously thought that prehistoric tetrapods evolved exclusively in tropical regions. The discovery of the new fossils show that four-legged vertebrates could have evolved anywhere in the world.