Diving Robot Discovers Life In Slow Lane

A deep-diving robot exploring the depths of the world's deepest water-filled sinkhole has found an amazing diversity of microbial life, even down where sunlight can't reach. The discovery re-affirms life's resilience and ability to thrive in extreme environments on Earth, and possibly on other planets as well, scientists say.

The robot, named DEPTHX, dove about 900 feet (275 m) deep toward the bottom of the Zacaton sinkhole in northeastern Mexico. Over almost 50 dives, the craft retrieved samples of water and microbes lining the limestone sinkhole.

Among these samples, researchers were able to identify more than 100 types of microbes, including three new phyla of bacteria never before discovered. The scientists also used data gathered by the robot's 54 onboard sonars to create high-resolution three-dimensional maps of the underground hole, which had never before been explored to such depths.

Sinkholes are depressions in the ground that are thought to be formed by the chemical dissolution of carbonate rocks, leaving behind a void that can fill up with water or air.

The Zacaton sinkhole is about 344 feet (105 m) across, and is filled with water that stays about 86 degrees Fahrenheit (30 degrees Celsius) throughout the year. The water contains sulfuric compounds that serve as a food source for some of the life within.

"It's a vertical column that goes straight down into the Earth," said researcher John Spear of the Colorado School of Mines. "We didn't know how deep before we went down."

Diving Robot Discovers Life In Slow Lane