Researchers in Antarctica have discovered the remains of a frog that dates back 40 million years, to a period when the frozen continent had a radically different climate.
The remains were found on Seymour Island, at the end of the Antarctic peninsula in a region that’s closest to the southern tip of South America.
The team, which was co-led by Thomas Mörs from the Swedish Museum of Natural History, found the skull and hip bone of a frog believed to be a part of the Calyptocephalellidae family.
More commonly known as helmeted frogs, these small amphibians are still found across South America, mostly in the lowlands of Chile, where temperatures are warm and humid.
It’s unlikely a helmeted frog could survive long in the freezing conditions of Antartica today, but the discovery offers new insight into just how long Antarctica’s formerly temperate period lasted.
‘The question is now, how cold was it, and what was living on the continent when these ice sheets started to form?’ Mörs said in an interview with Science News.
‘This frog is one more indication that in [that] time, at least around the Peninsula, it was still a suitable habitat for cold-blooded animals like reptiles and amphibians.’
In the past, scientists believe Antarctica was part of a larger supercontinent called Pangaea with what is now Australia and South America.
During that time, the region was covered with temperate rainforests similar to what’s currently found in New Zealand, which would have supported an entirely different set of creatures than are associated with Antarctica today.
Past research has found teeth and other fragments of marsupials dating from the pre-freeze period, but according to Mörs no one has yet found evidence of frogs.
Around 34 million years ago, Pangaea began to separate, and Antarctica began cooling and formed large glaciers that would eventually make it uninhabitable for most life.
Mörs’s team had begun their expedition in the hopes of learning more about what the terrain was like during that period and what exactly caused the cooling.
Mörs believes that learning more about the kinds of life the region supported could help scientists better understand what caused Antarctica’s climate to change so drastically.
‘It would be great to have more data for these [six million years] to get a better idea about the cooling process,’ he told Vice.