Wednesday, September 20, 2017

Is there life beneath the ice? Antarctica's mysterious caves

Via nzherald.co.nz by Jamie Morton

Hidden beneath the surface of the coldest, driest, windiest continent lie mysterious caves - some so warm, you could comfortably wear a T-shirt within them.

Now, a team of scientists has revealed evidence that animals and plants might exist in these extensive cave systems that have been hollowed out around Mt Erebus on Antarctica's Ross Island, the home of New Zealand's Scott Base.

Forensic analyses of soil samples from these caves, carried out by an international team including Kiwis, have turned up intriguing traces of DNA from algae, mosses and small animals.

"It can be really warm inside the caves - up to 25C in some caves," said Dr Ceridwen Fraser, of the Australian National University's Fenner School of Environment and Society.

There was also light near the cave mouths, and light filters deeper into some caves where the overlying ice was thin.


Most of the DNA found in the caves on Mt Erebus was similar to DNA from plants and animals - including mosses, algae and invertebrates - found elsewhere in Antarctica, but not all sequences could be fully identified.

"The results from this study give us a tantalising glimpse of what might live beneath the ice in Antarctica - there might even be new species of animals and plants," Fraser said.

Another scientist involved in the project, Professor Laurie Connell from the University of Maine, said these intriguing DNA traces did not conclusively prove plants and animals were still living in the caves.

"The next steps will be to take a closer look at the caves and search for living organisms," Connell said.

"If they exist, it opens the door to an exciting new world."

Microbial ecologist Professor Craig Cary, director of the Waikato University-based International Centre for Terrestrial Antarctic Research, said previous research had 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."

His Waikato University colleague Dr Charles Lee said there were 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," Lee said.

"They're really difficult to identify, get to and explore."

The research been published in the international journal Polar Biology and was supported by Antarctica New Zealand and the Marsden Fund.

It comes amid other new studies centring on Mt Erebus, which is infamous for the 1979 air crash that killed 257 people, but is also the world's southernmost active volcano and one of a handful with a persistent lava lake.

Kiwi scientists in one project have been working to create a 3D model of Mt Erebus' plumbing, or magmatic system, from source to surface.

Erebus also has magma formed from the rare and poorly understood rock type phonolite, which has also been found in some volcanoes that have produced devastating eruptions, including Pompeii in 79AD.

The project aimed to not only improve the knowledge of Antarctic geology but also to enable Antarctica to make a valuable contribution to understanding the mechanics of phonolitic magma systems across the world.

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