(Close-up of salt in Death Valley; Image: National Park Service)
Organisms dating to 34,000 years ago were recently found buried alive in California, according to a new GSA Today paper.
To put that time in perspective, Neanderthals were still marching around Europe. Woolly mammoths, saber-toothed cats, and numerous other now-extinct animals were going strong.
Salt-loving bacteria from Death Valley and Saline Valley, Calif., however, were just getting their proverbial second wind then, since the very same bacteria still thrives today.
“They’re alive, but they’re not using any energy to swim around. They’re not reproducing,” Brian Schubert, who discovered the bacteria, told OurAmazingPlanet. “They’re not doing anything at all except maintaining themselves.”
Schubert and colleagues Tim Lowenstein and Michael Timofeeff not only identified the living bacteria, but they also managed to reproduce it. Schubert grew the same organisms in his lab. He then sent some of the bacteria, still embedded in salt, to another lab, which also reproduced the prehistoric cells.
“So this wasn’t something that was just a contaminant from our lab,” Schubert said.
He and his team suspect that the microbes survived over the millennia thanks to an algae called Dunaliella, which also became trapped and encased in the salt.
“The most exciting part to me was when we were able to identify the Dunaliella cells in there,” Schubert said, “because there were hints that could be a food source.”
The findings demonstrate just how long-lived and durable some forms of life can be. If entire ecosystems exist embedded in a material such as salt, the discovery also strengthens the possibility that living organisms could be found on other planets. Evidence for salt deposits, for example, has been spotted on Mars.
The age of this newly found Death Valley bacteria may not even reflect the real limits of longevity on Earth. About a decade ago, a short paper in the journal Nature described 250-million-year-old bacteria. Since the results of that study weren’t reproduced, it remains controversial that an organism could still be alive at such an advanced age, but scientists haven’t yet completely ruled out the possibility.