They may have been frozen inside giant crystals for tens of thousands of years, but these ancient microbes are still kicking.
Miners discovered spectacular crystals in the Naica Mine below Chihuahua, Mexico, about a century ago. Since then, they’ve become a source of fascination for geologists, who have scoured the hot, acidic environments for signs of extremophiles (samples of life that can survive extreme conditions).
In particular, what they’ve found is that microbes up to 50,000 years old have sat dormant inside small blemishes in the crystals—little nooks where fluids have accumulated. The team of scientists was then able to “reawaken” these sleeping bacteria and archaea, which process energy from rock minerals, back in the lab.
NASA Astrobiology Institute director Penelope Boston announced the finding at a meeting of the American Association for the Advancement of Science this weekend.
Here’s Victoria Jaggard, reporting for National Geographic:
Boston took samples from pockets of fluid trapped inside the crystals in 2008 and 2009, under the auspices of New Mexico Tech. Her team was able to “wake up” dormant microbes in that fluid and grow cultures, she revealed today at the meeting. The organisms are genetically distinct from anything known on Earth, according to her team’s analysis, although they are most similar to other microbes found in caves and volcanic terrain.
Previous work dated the oldest crystals in the cave at half a million years. Based on those calculations for the crystal growth rate, her team thinks the organisms they have growing in the lab had been inside their glittering cocoons for somewhere between 10,000 and 50,000 years.
There are some concerns that these microbes are merely the result of previous human contamination inside the caves, but Boston believes that the diverse microbial community she’s witnessed there proves otherwise.
If the microbes have in fact been there for as long as scientists suspect, they could help elucidate the kinds of life we might find in other parts of the Solar System—and how they manage to survive in strange, harsh environments.