Potential New Antarctica Bacteria Actually Contamination

Late last week, a Russian news outlet reported that scientists at Antarctica's Lake Vostok, buried under miles of ice, said they had found bacteria that appeared to be new to science. Now, the head of that lab has said the signature is actually just contamination, leading outside researchers to say that the Russian team rushed too quickly to announce the possibility of new bacterial life.

Russian news media reported last week that the team had found DNA from a microbe that did not appear in databases and is only 86 percent similar to others on Earth — considered a reliable threshold of new life.

On Monday (March 11), the lab analyzing the finding said it was not new bacteria that generated the signal, but contamination.

"We found certain specimens, although not many. All of them were contaminants," laboratory head Vladimir Korolyov said in a quote attributed in media reports to the Interfax news agency.

The quick backtrack illustrates the danger of bypassing peer review when announcing new results, Peter Doran, an Arctic and Antarctic researcher at the University of Illinois at Chicago, told OurAmazingPlanet.

'You can say anything you want in a press release'

Peer review is the scientific process that all findings must undergo before work is published, generally in the form of a paper in a scientific journal. The research comes under the scrutiny of other scientists in the field and is validated and questioned before anything goes to print. That's not the case in a news report.

For that reason, the scientists who OurAmazingPlanet spoke with said that it was hard for them to discuss why the Russians failed since they do not even know, for example, what contaminates were found in the lab. That information could take weeks or months to surface.

"You can say anything you want in a press release," Doran said. "The peer review literature [by contrast] is very controlled. It needs to be substantiated, and written in clear language."

"I tell my students," he continued, "don't trust anything you read in the popular press. Even if there is a paper, there's often a disconnect between what is in the paper and in the popular press."

Peer review, however, can take years, acknowledged David Pearce, a researcher with the British Antarctic Survey who worked on a similar British effort to drill into buried Lake Ellsworth. (That effort failed and is being subject to a review board. The results should be published around May, at which point the British will decide whether to try again.) [Extreme Antarctica: Amazing Photos of Lake Ellsworth]

Taxpayers are often impatient to find out what is going on, Pearce said, and the press works to fill that need. A balance must be struck between these needs, he added.

"It's important [the public] is kept informed of what's going on, and the interesting things that are coming out," Pearce said. Science, by contrast, requires time and careful thought.

"You do want to find out what's happened to the research money," he added, "but you don't want to say too much too soon."

Sterilization part of best practice

The Russian researchers not only faced challenges concerning announcing their findings, but also scientific challenges in their quest to discover life.

It's still not known what kind of life, if any, lies below the 2 miles (3 kilometers) of ice that sits on top of Lake Vostok. As far as researchers know, the underground freshwater has been lying there untouched for more than a million years.

Confirming that any possible signature of life is not a contaminant is complicated, to say the least.

There's a strict protocol the Americans strive to follow in Antarctica, said Doran, who is familiar with the practices of the U.S. Whillans Ice Stream Subglacial Access Research Drilling project (WISSARD) team that worked this year at Antarctica's Lake Whillans.

Doran could not speak specifically to the Russians, but said the American work demonstrates a good methodology.

In WISSARD's case, it involves sterilizing all the equipment with hydrogen peroxide gel or a similar product, then hermetically sealing them in bags for shipment. Scientists on-site sterilize the water in the drill system through several steps that include filters and life-killing ultraviolet radiation.

As the drill progresses through the ice, the scientists monitor cell counts to make sure there are no unexplained jumps.

WISSARD recently announced life findings of its own, but Doran was equally skeptical of that until a paper comes out confirming the work. [Gallery: Finding Life in a Buried Antarctic Lake]

To the WISSARD announcement, Doran said, "I understand how it happened. There are embedded reporters in the field with them. They are sitting around the dinner table together, and drinking Scotch together, and the reporters are right there [when scientists say] 'Our cell counts are way up when we've gone into the lake water.'"

"Of course that gets reported, but without the peer review literature, it's still a violation of how the standard things are done," Doran said.

Follow Elizabeth Howell @howellspace. Follow OurAmazingPlanet @OAPlanet, Facebookand Google+.

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What Antarctica Looked Like Before the Ice

Like Alaska's mighty Yukon, a broad river once flowed across Antarctica, following a gentle valley shaped by tectonic forces at a time before the continent became encased in ice. Understanding what happened when rivers of ice later filled the valley could solve certain climate and geologic puzzles about the southernmost continent.

The valley is Lambert Graben in East Antarctica, now home to the world's largest glacier. Trapped beneath the ice, the graben (which is German for ditch or trench) is a stunning, deep gorge. But before Antarctica's deep freeze 34 million years ago, the valley was relatively flat and filled by a lazy river, leaving a riddle for geologists to decode: How did Lambert Graben get so steep, and when was it carved?

The key to Lambert Graben's history was found in layers of sediments just offshore, in Prydz Bay. In a new study, Stuart Thomson, a geologist at the University of Arizona (UA) in Tucson, looked into the past by decoding sands deposited by the river, and the messy piles left behind by the glacier. The river sands are topped with a thick layer of coarser sediment that signals the onset of glacial erosion in the valley, the researchers found. The erosion rate more than doubled when the glaciers moved in, Thomson said.

"The only way that could happen is from glaciers," he said. "They started grinding and forming deep valleys."

Understanding when glaciers first wove their way across Antarctica will help scientists better model the ice sheet's response to Earth's climate shifts, the researchers said.

"There's a big effort to model how glaciers flow in Antarctica, and these models need a landscape over which glaciers can flow," Thomson told OurAmazingPlanet. "Once these models can predict past changes, they can more accurately predict what will happen with future climate changes."

The sediments also hold clues to the tectonic evolution of East Antarctica, and a mountain range buried beneath the vast, thick ice sheet. [Album: Stunning Photos of Antarctic Ice]

The findings are detailed in the March 2013 issue of the journal Nature Geoscience.

History of the ice

Lambert Graben formed during the breakup of Gondwana, an ancient supercontinent, a process that happened in stages. Antarctica, India and Africa tore apart in the Late Cretaceous (about 80 million years ago). The split created long, linear valleys oriented perpendicular to the continental coastlines. At the time, Earth's climate was warmer than it is today, and as Antarctica moved southward, settling into its home over the South Pole, the continent teemed with plants and animals.

Scientists can partially reconstruct this past environment with fossils and through radar that peers beneath the ice to map the shapes of the rock below. A 3D map of Antarctica today shows chasms carved by glaciers, rugged mountains and other remnants of its warmer existence.

But the surveys tell nothing about how the landscape looked before the ice carved out all those features. "People have speculated when the big fjords formed under the ice," Thomson said. "But no one knows for sure until you sample the rocks or the sediments."

Thomson and his colleagues analyzed sediments drilled from the ocean floor just offshore of Lambert Glacier, as well as from onshore moraines, the rock piles pushed up by glaciers. Tests on minerals in the sands and muds helped them figure out when and how fast the surface eroded.

Here's what the sediments say: From about 250 million to 34 million years ago, the region around Lambert Glacier was relatively flat, and drained by slow-moving rivers, Thomson said. About 34 million years ago, which coincides with a cooling of Earth's climate, big glaciers appeared, shaping the spectacular valley now hidden under thick ice.

"It seemed like it occurred very early on, 34 [million] to 24 million years ago," Thomson said. Erosion slowed dramatically as the ice sheet stabilized about 15 million years ago, he said.

Some 5,250 to 8,200 feet (1.6 to 2.5 kilometers) of rock have since disappeared, ground down by glaciers and carried away by the ice, according to the study.

"Glaciers can carve deep valleys quickly — and did so on Antarctica before it got so cold that the most of it got covered by 1 or 2 miles [1.6 to 3.2 km] of thick, stationary ice," Peter Reiners, a UA geologist and study co-author, said in a statement.

Clues to buried mountain range

Lambert Graben extends about 375 miles (600 km) inland, ending at one of Antarctica's most enigmatic features — an entombed mountain range called the Gamburtsev Mountains. Buried under the ice, the mountains rose during Gondwana's rifting. Geologic evidence suggests two pulses of upliftfrom rifting events about 250 million years ago and 100 million years ago pushed up the jagged peaks.

But Thomson and his colleagues did not find evidence in the sediments for a second uplift phase 100 million years ago. The river sands contain minerals from the Gamburtsev Mountains, and the tiny grains suggest the mountains got their height with one tectonic push.

"This underscores both the mountain range's remarkable age and the extraordinary degree of subglacial landscape preservation," writes Darrel Swift in an accompanying article in Nature Geoscience. Swift, a geologist at the University of Sheffield in the United Kingdom, was not involved in the study.

Email Becky Oskin or follow her @beckyoskin. Follow us @OAPlanet, Facebook or Google+. Original article on LiveScience's OurAmazingPlanet.

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