Life forms that could be 50,000 years old found in caves in Mexico

The bizarre, ancient microbes and viruses found living in crystals in extremely punishing conditions deep in an abandoned lead and zinc mine

In a Mexican cave system so beautiful and hot that it is called both fairyland and hell, scientists have discovered life trapped in crystals that could be 50,000 years old.

The bizarre and ancient microbes were found dormant in caves in Naica, in Mexico's northern Chihuahua state, and were able to exist by living on minerals such as iron and manganese, said Penelope Boston, head of Nasa's Astrobiology Institute.