Microbes discovered in Mexican crystal cave may have survived up to 50,000 years

Scientists have discovered long-dormant microbes trapped in giant crystals in the famous Naica mine of Mexico and have estimated that these organisms may have survived 10,000 to 50,000 years.

The Naica mine is a lead, zinc and silver mine located in the northern Mexican state of Chihuahua and contains extremely large selenite crystals measuring as large as 1.2 meters in diameter and 15 meters long.

The environment inside the crystal cave is very hot and humid, with the high temperature at roughly 60 degrees Celsius.

With no light deep inside the cave, any forms of life has to rely on chemosynthesis, the process to obtain energy released from chemical reactions instead of the energy of sunlight, to survive.

Scientists had identified microbes living in the walls and other nearby areas in the crystal cave. But the microbes discovered by the team led by Penelope Boston, director of NASA's Astrobiology Institute in Moffett Field, California, were trapped in small voids and cracks inside the massive crystal needles.

Using sterile tools, Boston's team obtained samples of these microbes and were able to revive them in the lab.

"Other people have made longer-term claims for the antiquity of organisms that were still alive, but in this case these organisms are all very extraordinary - they are not very closely related to anything in the known genetic databases," said Boston at a press conference during the annual meeting of the American Association for the Advancement of Science held in Boston on Friday.

These special microbes leave Boston and her team fairly confident that the samples were not contaminated with other microbes and that their age estimates for the crystal-trapped microbes is solid.

Studies like these show how resilient life can be to adapt to and thrive in extremely harsh conditions, including on other planets beyond Earth.

"Any extremophile system that we're studying actually allows us to push the envelope of life further, and we add it to this atlas of possibilities that we can apply to different planetary settings," Boston said.

"If you took some of these organisms from Earth and put them elsewhere, they may do just fine," she added. Endi