Year in review: Life thrives under Antarctica

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An unseen ecosystem flourishes in the darkness, entombed beneath 800 meters of ice. In 2014, researchers shed light on this microbial community.

Rivers and about 400 subglacial lakes traverse the land sealed beneath Antarctica’s 14-million-square-kilometer ice sheet. For decades, scientists speculated about what strange creatures might lurk in the frigid waters. In 1999, researchers found life in an ice core drilled above Lake Vostok in East Antarctica. But critics said the scarce cells were simply contamination from the drilling process.

Since then, researchers from Russia, the United Kingdom and the United States have sought more convincing proof of life. In January 2013, the U.S. team reported finding live cells in water from Lake Whillans, 800 meters below the West Antarctic ice sheet (SN: 3/9/13, p. 12). In August, the team announced that it had found not only life but a thriving ecosystem there (SN: 9/20/14, p. 10).

The team identified genetic traces of 3,931 microbial species or groups of species in water from the lake (bacteria cultured from the lake are shown above). The abundance of bacteria and single-celled organisms called archaea was a surprise. Project scientist Brent Christner of Louisiana State University compared the number of microbes to that found in a typical surface lake or ocean.

The finding bolsters the idea that life exists elsewhere in the solar system, Christner says, such as under Mars’ polar ice caps or in a subsurface ocean on Jupiter’s frozen moon Europa.