14 DAY TRIAL // An Antarctic lake located under miles of solid ice has just revealed one of its secrets, when researchers found a colony of bacteria that apparently first developed some 140,000 years ago. Its cells are apparently still alive today, and experts expect many similar instances to be discovered.
The thing about this research site, called Lake Vostok, is that it was covered by ice sheets when Antarctica first froze over. Over millions of years, meter upon meter of ice accumulated over the lake, cutting off all contact with the outside world.
As such, it can be expected that organisms which got trapped within and survived were able to adapt to the new conditions, and endure. Experts are very interested in this aspect, because studies such as the one carried out on this lake could inform future space missions.
The conditions bacteria and microbes survive in underneath the ices are similar to the ones they would be exposed to on the Saturnine moon Enceladus or the Jovian moon Europa. Both these celestial bodies are covered in thick ice crusts, but harbor a liquid ocean underground.
In one of the first studies to be conducted on Lake Vostok since Russian drillers managed to reach its surface, experts discovered a type of nitrifying bacteria that appears to have mastered the recipe for immortality, Daily Galaxy reports.
The study was conducted by expert Buford Price, who is based at the University of California in Berkeley (UCB) and Todd Sowers, from the Pennsylvania State University (Penn State).
Past studies conducted on long-lived microorganisms demonstrate that these lifeforms survive either by stopping their metabolism and entering a hibernation mode, or by maintaining a low, yet steady metabolism. The newly-found bacteria were found to be “fans” of the latter method.
“Extremely low expenditures of survival energy enable microbial communities in extreme environments to survive indefinitely,” the experts say. Indeed, the new organisms apparently lived in water cooled to minus 40 degrees Celsius for more than 140,000 years.
The new work also implies that we should reassess the theoretical limits between which life can exist. “Our results disprove the view that the lowest temperature at which life is possible is minus 17 degrees Celsius in an aqueous environment,” the team explains.
If life can be discovered in the harsh environment of Lake Vostok, then is there really a reason to believe that similar organisms do not exist in the same conditions on other moons in the solar planet? Astrobiologists say that to think that of Enceladus, Europa or even Mars would be narrow-minded.