Deepest-Dwelling Life Forms Found

Scientists have found the most extreme single-celled Archaea yet, subsisting on methane nearly three miles below the surface

By Matt Ransford
Posted 05.27.2008 at 12:42 pm

Hot Springs: Archaea were first discovered in extremely hostile environments, such as this hot spring in Yellowstone National Park Photo by the U.S. National Park Service

The Archaea group of organisms has just gotten a little bigger—and quite a bit deeper. Known to scientists as extremophiles—organisms which live in places inhospitable to other forms of life—the Archaea group is home to many single-celled creatures capable of thriving in environments of exceptional temperature, pressure, and acidity. The latest member has been discovered off the coast of Newfoundland, Canada, under 2.8 miles of water and a mile of rock. Previously, the deepest these organisms had been found underground was half as far.

These new Archaea were discovered in a sediment core extracted by a research ship. The scientists analyzing the sample have surmised that the organisms are able to survive off of methane released from hydrocarbons in the stone. The tremendous heat and pressure at that depth cooks the fossil fuel, breaking it down into compounds potentially useful to the Archaea. How they arrived in the bedrock is also something of a mystery; the two leading theories are that they were brought down by water currents or that they have been living in the rock since the days it was formed millions of years ago.

[Via the Guardian]