Hoping to shed light on the origins of life, speleologist Francesco Sauro investigates some of the world's darkest places.

His expeditions have led to the discovery of the world’s largest quartzite cave system, the Imawari Yeuta; the mineral rossiantonite; a species of blind cave fish; and previously unclassified bacteria. But it’s South America's mysterious tepuis, or table mountains—home to ancient geologic and biologic treasure chests—that beckon the Rolex Laureate.

"The most fascinating thing is they have been untouched for millions of years—like a giant library where you can find information about your ancestors, about life in the past,'' he says.

Microbiologist and fellow Rolex Laureate Hosam Zowawi, who accompanied Sauro on two South American cave expeditions, says the