Lake Vostok Contains Living Organisms Swimming Beneath 4 Kilometers of Ice

As scientists continue to study Antarctica's frozen mysteries, they have discovered that fish may exist in a lake four kilometers below the sheet of ice, BBC reported.

Lake Vostok, discovered in 1956 by the Russians and was mapped in the 1990's by the British, is 200 meters below sea level and is part of a complex system of rivers and lakes below the ice of Antarctica. The lake covers 15,000 square km and is 800 meters deep.

Scientists discovered the genetic material in ice drilled from near the surface of the lake, thousands of meters down. The material contained signatures of organisms, like bacteria, normally associated with marine mollusks, crustaceans and fish.

The findings were reported in a paper published in the journal PLOS One. The researchers also acknowledged that the genetic material could be traces of past contamination.

The team reported a large number of bacterial sequences were from "animal commensals, mutualists and pathogens... including those associated with annelids, sea anemones, brachiopods, tardigrades and fish."

94 percent were from bacteria, while six percent were multi-cellular organisms, also known as eukaryotes. Only a few connections were made to single-celled microbes.

The team also discovered organisms that exist in extremely hot environments and concluded that they could come from volcanic hydrothermal vents on the ocean floor.

If such vents existed in Vostok, they could "provide sources of energy and nutrients vital for organisms living in the lake," the team study said.

Vostok is the largest of about 375 bodies of water beneath the ice of Antarctica. They are kept from freezing like the ultra-thick ice above them by the heat from the rockbed below and the pressure of the ice above.

Astrobiologists believe the conditions beneath the ice resemble conditions beneath the surface of Jupiter's icy moons. If true, outer Solar System moons would be ideal for alien organisms to exist.

(The author of this artcle changed various instances of measurement units; from "800 km" to "800 m" and from "thousands of kilometers" to "thousands of meters.")