It seems as though some worms have crawled down to where no other land animal dares to tread or should we say wriggle - 2.2 miles below the surface of the Earth. Earlier this month, scientists discovered a new species of roundworm dubbed Halicephalobus mephisto or 'devil worm' inside the goldmines of the Witwatersrand basin, near Johannesburg.

Prior to this discovery, researchers believed only single celled organisms could survive at such depths, where the oxygen level is less than one percent that found in oceans, food is almost non-existent and temperatures, so extreme.

In fact, when the research team, led by Princeton University's Dr. Tullis Onstott first discovered the tiny worm, they were no sure whether the worms had emerged from a rock or been trekked down by miners.

In order to find out Dr Onstott and his colleague Gaetan Borgoni from Belgian's University of Ghent, spent a year, boring holes into the ground and drawing out samples of water to look for more evidence - After scouring through 8,343 gallons, they finally came across a few of the tiny creatures that measure a mere 0.5 millimeter long.

And it turns out that these ringworms are not new immigrants either - Further tests proved that they have been living there for at least 3,000 years. The scientists believe that they were probably first carried down to such depths by ancient rainwater. Now that they have found one multi-cell organism, the team plans to continue the research in the hope that there may be many more - So stay tuned!

Resources :National Geographic.com, bbc.co.uk