New Discovery: Blood-Red Worms That Thrive in a Toxic Cave (EXCLUSIVE VIDEO)

June 3, 2016 - It's wet, muddy, slimy, and smells like rotten eggs: Sulfur Cave in Steamboat Springs, Colorado, is full of gases so toxic that a person who enters would pass out after just a few breaths. But that didn't stop David Steinmann of the Denver Museum of Nature & Science. Donning a special respirator, he first explored the cave in 2007. In this extreme environment, devoid of sunlight, Steinmann found clumps of tiny blood-red worms, each one just an inch long and as thin as a pencil lead. Now genetic analysis has confirmed that the worms are a new species that may not be found anywhere else on Earth. These tiny worms could even offer clues to the kinds of life that might be found on other planets.

Read more about the wormy wonders that live in Sulfur Cave on National Geographic's Phenomena.