Our Changing World: Searching for extreme life

9:17 am today

Claire Concannon, for Our Changing World

Two people in yellow hazmat suits wearing beanies and eye goggles kneel in the snow and dark volcanic rock of a mountain slope. Volcanic steam makes the scene below hazy: black outcrops peeking out of smooth snow and ice. They are fixated on a frame contraption sitting on the snow between them, with two chilly bins resting nearby.

Professor Matthew Stott and Pepper Cook on the slopes of Mt Erebus. Photo: Stephen Noell

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Professor Matthew Stott of the University of Canterbury is fascinated by the extremophiles he studies - microbes that live at the extreme ends of survivability.

These living things challenge our ideas of what life is capable of, living in the hottest, coldest, saltiest and most acidic environments possible.

Mt Erebus microbes

Matthew's latest field site might be the most extreme yet: on the slopes of the world's southernmost active volcano, Mt Erebus on Ross Island in Antarctica.

A man wearing a thick orange jacket, blue beanie and sunglasses stands smiling at the camera on an expanse of ice and snow criss-crossed with vehicle tracks. A snow-cloaked volcano is visible in the background, rising into a bluebird sky.

Professor Matthew Stott and Mt Erebus, 2024. Photo: Megan Nicholl / Antarctica New Zealand

The volcano's chemistry is unique, the outside temperatures are -30 to -40°C, and the soil temperatures are 60 to 70°C.

"Frankly, it's quite nuts to go there with cold weather gear on trying to sample hot microorganisms. It doesn't quite make sense in your brain," he says.

In collaboration with scientists from the University of Waikato and the University of Southern California, Matthew has been involved in a project to investigate these microbes living on the edge.

A person wearing a bright yellow hazmat suit, dark balaclava and eye goggles stands on a slope on dark volcanic rock and snow.

Scientists wear hazmat suits over their cold-weather gear to do their mahi on Mt Erebus. Photo: Supplied

Microbe halfway houses

One of the issues microbiologists around the world face is how to grow these extremophile microbes in a lab in order to study them, says Matthew - especially those that feed on very different gases or metals, or that thrive in extreme temperatures.

"Globally, we've only really managed to grow maybe 1 to 5 percent of all organisms on Earth," he says.

To combat this, the team are using microbe 'halfway houses' on Mt Erebus.

They collect soil samples from the slopes, bring them back to the lab at Scott Base, and then mix the microbes from the soil with some water and nutrients before putting them into little containers that go back up onto the mountain.

Two people in bright yellow hazmat suits, beanies and eye goggles crouch on the dark volcanic soil strewn with snow on a slope. Volcanic steam rises around them into a bluebird sky.

Jon Tyler (left) and Dr Stephen Noell on Tramway Ridge, Mt Erebus, 2023. Photo: Matthew Stott

The microbes are left on the mountain for a few weeks (ideally, happily growing away) before being collected and brought back to New Zealand for study.

The team also set up containers to be left on the mountainside over winter, for collection in the next field season.

While previous investigations into Erebus microbes have led to commercial applications, Matthew says the goal in this case is to better understand how life at the edge works - whether it's figuring out how certain sunlight-loving microbes survive the long dark winters, or identifying unique microbes that are not found anywhere else on Earth.

Their investigations might also give insights into extraterrestrial microbiology - what simple life might look like on other planets.