Bacteria in Antarctica

An ancient ecosystem has just been discovered isolated in a pool of dark, salty water underneath 500m of ice in Antarctica.

The bacterium in this ecosystem has managed to survive millions of years by evolving to be able to live without light or oxygen. They had to do this because the Taylor glacier on the East Antarctic ice sheet covered it around 2 millions years ago. Scientists think that the temperature of the pool is around -10°C, however the water hasn't frozen because it is so salty (It contains about four times as much as seawater!).

Scientists made this remarkable discovery while they were analysing at some water samples from a place called 'Blood Falls' in Antarctica where there is a blood-red coloured stain on the Taylor glacier that comes from the rust in the water.  

Blood Falls in Antarctica

"This briny pond is a unique time capsule from a period in Earth's history," Jill Mukucki said, who led the research that is being done at Dartmouth College in New Hampshire, US. "I don't know of any other environment quite like this on Earth."

So far she has found 17 different types of 'marine microbe', including a bacterium called 'Thiomicrospira arctica' (try saying that 10 times really fast!) but she thinks that there could be around 30 types living in the pool!

She has also tested the microbes by taking samples of their DNA and she has found that they are remarkably similar to modern marine microbes.

Most microbes survive by using 'photosynthesis', where they lie and soak up lots of sun and then convert it to energy for them to use. Plants use this as well, that's why their leaves are green because they contain something called 'chlorophyll' which helps soak up the sun. But these unique microbes apparently manage to live without oxygen by 'breathing' iron that they get from the bedrock beneath the glacier and they are thought to feed on an 'organic matter' (something that is living) that was trapped in the pool with them.

Finding out more about these curious microbes might help us to explain just how life managed to survive through a time known as 'Snowball Earth', when huge ice sheets from both poles advanced towards the middle of the earth (the equator), which covered the whole world in ice.

Images sourced from: http://www.guardian.co.uk/science/2009/apr/16/extremophiles-ecosystem-antarctica-taylor-glacier

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