Australian scientists investigating ice caves under Antarctica’s glaciers say they are so warm they could support animals and plants.

Around Mount Erebus, an active volcano on Ross Island in Antarctica, steam has hollowed out extensive cave systems.

Dr Ceridwen Fraser from the ANU Fenner School of Environment and Society says forensic analyses of soil samples from these caves has revealed intriguing traces of DNA from algae, mosses, and small animals.

"It can be really warm inside the caves, up to 25 degrees Celsius in some caves," Fraser says.

"You could wear a T-shirt in there and be pretty comfortable. There’s light near the cave mouths, and light filters deeper into some caves where the overlying ice is thin."

Most of the DNA found in the caves is similar to DNA from plants and animals found elsewhere in Antarctica but not all could be fully identified.

"The results from this study give us a tantalizing glimpse of what might live beneath the ice in Antarctica – there might even be new species of animals and plants," she says.

The next step will be to take a closer look at the caves and search for living organisms.

The scientists explain:

Co-researcher Professor Craig Cary, from the University of Waikato in New Zealand, says previous research found that diverse bacterial and fungal communities lived in Antarctica’s volcanic caves.

"The findings from this new study suggest there might be higher plants and animals as well," Professor Cary said.

Dr Charles Lee, another co-researcher from the University of Waikato, says there are many other volcanoes in Antarctica, so subglacial cave systems could be common across the icy continent.

"We don’t yet know just how many cave systems exist around Antarctica’s volcanoes, or how interconnected these subglacial environments might be. They’re really difficult to identify, get to and explore," Dr Lee says.

The research, published in the international journal Polar Biology, was funded by the Australian Research Council, with sample collection supported by Antarctica New Zealand and the Marsden Fund.