In some of the planet’s biggest caves, primitive life has been existing for millions of years in isolation. Could it hold answers to evolution on Earth?

Sometimes, it is the life that’s hidden away in the dark that is the most intriguing.

Italian scientist Francesco Sauro has been studying the microbial life that inhabits caves for years. The Italian scientist believes that these simple forms of life – sometimes isolated from the rest of our planet for many millions of years – may hold some valuable clues to our evolutionary journey.

When he discovered a huge cave in Venezuela’s remote Auyan tepui region, he found a new mineral – rossiantonite – and microbes that had developed cut off from the rest of the planet.

“Caves are witness to geographic history,” he says. “They preserve much more than the surface. They are archives of time, of the evolution of the landscape and life.”

Watch the video above to see why Sauro believes caves like this can shed light on the earliest days of life on Earth.

Getty Images 74076688

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