Microbes that 'breathe iron' are found in Antarctic

Unique organisms have developed from more than a million years in isolation

A community of microbes that have lived cut off from the rest of the world for more than 1.5 million years has been discovered beneath a vast glacier in the Antarctic.

The organisms have survived in total darkness on nothing but the minerals and long-decayed organic matter that were also trapped at the base of the glacier. Instead of breathing oxygen, they have learnt to "breathe" iron to produce energy.

The discovery of the microbes demonstrates the tenacious capacity of life to survive in the most extreme environments, and raises the prospect that it may one day be possible to find life in equally extreme environments both on Earth and on other planets.

"It's a bit like finding a forest that nobody has seen for 1.5 million years," said Professor Ann Pearson of Harvard University, one of the scientists who made the discovery. "Intriguingly, the species living there are similar to contemporary organisms, and yet quite different – a result, no doubt, of having lived in such an inhospitable environment for so long."

The scientists discovered the microbes by analysing the very salty water flowing out of a crack in the wall of the Taylor Glacier in the McMurdo Dry Valleys of East Antarctica. The glacier is famous for its "Blood Falls", an outflow of rusty-red mineral deposits first discovered in 1911.

The brine seeping from the glacier contained no oxygen, indicating that it had been isolated from the atmosphere, but it did include the telltale genetic signatures of living organisms living beneath the mass of ice.

The scientists believe that the microbes are descended from a population of marine organisms that once lived in an ancient ocean that had become a landlocked briny pond before being covered in the glacier between 1.5m and 2m years ago. The exact size of the pond is not known but it lies more than 1,300 feet below ice, about 2.5 miles from Blood Falls.

"This briny pond is a unique sort of time capsule from a period in Earth's history," said Jill Mikucki of Dartmouth College, New Hampshire, the lead author of the study, published today in the journal Science.

The scientists obtained a cold, clear sample of the brine as it flowed from a crack in the glacier. "When I started running the chemical analysis on it, there was no oxygen. That was when this got really interesting. It was a real Eureka moment," Dr Mikucki said.

"The brine is about four times more salty than seawater and so it does not freeze, despite being at a temperature of about -10C. The chemical analysis showed that the genes of the microbes found in the brine were closely related to the genes of modern-day marine microbes even though they have been cut off from the ocean for more than a million years. The salts associated with these features are marine salts, and given the history of marine water in the dry valleys, it made sense that subglacial microbial communities might retain some of their marine heritage," Dr Mikucki said.

Scientists at the site are using the same sort of analytical techniques to search for extreme terrestrial life forms that they hope to use in the search for life on Mars and Europa, the frozen moon of Jupiter.

Suggested Topics
Arts and Entertainment
Kirk Cameron is begging his Facebook fans to give him positive reviews
film
Sport
premier leagueMatch report: Arsenal 1 Man United 2
Arts and Entertainment
Jason goes on a special mission for the queen
tvReview: Everyone loves a CGI Cyclops and the BBC's Saturday night charmer is getting epic
Sport
Jonny May scores for England
rugby unionEngland 28 Samoa 9: Wing scores twice to help England record their first win in six
PROMOTED VIDEO
News
ebooksNow available in paperback
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Recruitment Genius: Senior Project Manager

£45000 - £65000 per annum: Recruitment Genius: This is a fantastic opportunity...

Recruitment Genius: Shopfitter

Negotiable: Recruitment Genius: This is an opportunity to join a successful an...

Recruitment Genius: Digital Sales Account Manager

£25000 - £30000 per annum: Recruitment Genius: A Digital Sales Account Manager...

Recruitment Genius: Trainee Sales Account Manager

£20000 - £25000 per annum: Recruitment Genius: A Trainee Sales Account Manager...

Day In a Page

Mau Mau uprising: Kenyans still waiting for justice join class action over Britain's role in the emergency

Kenyans still waiting for justice over Mau Mau uprising

Thousands join class action over Britain's role in the emergency
Isis in Iraq: The trauma of the last six months has overwhelmed the remaining Christians in the country

The last Christians in Iraq

After 2,000 years, a community will try anything – including pretending to convert to Islam – to avoid losing everything, says Patrick Cockburn
Black Friday: Helpful discounts for Christmas shoppers, or cynical marketing by desperate retailers?

Helpful discounts for Christmas shoppers, or cynical marketing by desperate retailers?

Britain braced for Black Friday
Bill Cosby's persona goes from America's dad to date-rape drugs

From America's dad to date-rape drugs

Stories of Bill Cosby's alleged sexual assaults may have circulated widely in Hollywood, but they came as a shock to fans, says Rupert Cornwell
Clare Balding: 'Women's sport is kicking off at last'

Clare Balding: 'Women's sport is kicking off at last'

As fans flock to see England women's Wembley debut against Germany, the TV presenter on an exciting 'sea change'
Oh come, all ye multi-faithful: The Christmas jumper is in fashion, but should you wear your religion on your sleeve?

Oh come, all ye multi-faithful

The Christmas jumper is in fashion, but should you wear your religion on your sleeve?
Dr Charles Heatley: The GP off to do battle in the war against Ebola

The GP off to do battle in the war against Ebola

Dr Charles Heatley on joining the NHS volunteers' team bound for Sierra Leone
Flogging vlogging: First video bloggers conquered YouTube. Now they want us to buy their books

Flogging vlogging

First video bloggers conquered YouTube. Now they want us to buy their books
Saturday Night Live vs The Daily Show: US channels wage comedy star wars

Saturday Night Live vs The Daily Show

US channels wage comedy star wars
When is a wine made in Piedmont not a Piemonte wine? When EU rules make Italian vineyards invisible

When is a wine made in Piedmont not a Piemonte wine?

When EU rules make Italian vineyards invisible
Look what's mushrooming now! Meat-free recipes and food scandals help one growing sector

Look what's mushrooming now!

Meat-free recipes and food scandals help one growing sector
Neil Findlay is more a pink shrimp than a red firebrand

More a pink shrimp than a red firebrand

The vilification of the potential Scottish Labour leader Neil Findlay shows how one-note politics is today, say DJ Taylor
Bill Granger recipes: Tenderstem broccoli omelette; Fried eggs with Mexican-style tomato and chilli sauce; Pan-fried cavolo nero with soft-boiled egg

Oeuf quake

Bill Granger's cracking egg recipes
Terry Venables: Wayne Rooney is roaring again and the world knows that England are back

Terry Venables column

Wayne Rooney is roaring again and the world knows that England are back
Michael Calvin: Abject leadership is allowing football’s age-old sores to fester

Abject leadership is allowing football’s age-old sores to fester

Those at the top are allowing the same issues to go unchallenged, says Michael Calvin