Scientists claim to have discovered a 32,000-year-old bacterium. Their colleagues are skeptical
NASA scientists report that they recently discovered, in a frozen lake in Alaska, a "dormant" bacteria that is 32,000 years old. If the discovery is confirmed, it means that additional pockets of ancient life may be found in frozen layers of soil or silt on the sea floor. The bacterium's robustness even hints at the possibility of the existence of life on the surface of Mars, in places similar to the frozen sea on the planet, the discovery of which researchers reported last week.
The bacterium was discovered near "Fox Trench", a tunnel dug by a US Army research team deep into Pleistocene ice layers. Dr. Richard Huber, a biologist at NASA, said that when he visited the cave and examined a layer of ice that froze 32,000 years ago, he noticed an area with a different shade. Huber and his colleague, Dr. Elena Picota, took samples from the area to their laboratory and discovered bacteria, which began to move when the ice melted.
The bacterium that was discovered is of a species unknown to science, but it resembles a group of bacteria known for their ability to withstand cold conditions. Huber stated that he believes that the bacterium was unable to divide during the thousands of years of being in the ice, and for that reason the bacteria that were thawed in the laboratory should be 32,000 years old - the time that has passed since the lake was last in a liquid state.
Other researchers announced in 2000 that they had succeeded in "bringing back to life" 250-million-year-old bacteria discovered in fluids stored in rock in Pennsylvania, but the report was met with skepticism by the scientific community. One of the reasons is that DNA is not a stable chemical substance and its state changes very quickly, certainly under conditions where metabolism stops.
Dr. Eske Willerslav from the University of Oxford in England, an expert on the bacteria found in Ice-Ed, said that the discovery is "extremely interesting, if it is true." According to him, there is a possibility that NASA researchers did not rule out the possibility that the ice was contaminated by modern-day bacteria.
