Researchers from Texas A&M University at Galveston think they’re closer to discovering alien life forms – and they’re looking in the Bahamas.

Underwater caves hold clues to how life formed on Earth millions of years ago, housing microbes that can survive in environments with very low amounts of oxygen and light. There are tens of thousands of underwater caves across the globe, but less than 5 percent have ever been explored.

“We know more about the far side of the moon than we do about these caves right here on Earth,” said Tom Iliffe, professor of marine biology. “If life exists elsewhere in our solar system, it most likely would be found in water-filled subterranean environments, perhaps equivalent to those we are studying in the Bahamas.”

Iliffe’s team examined three caves – two on Abaco Island and one on Andros Island. They found layers of bacterial microbes in each cave with specialized forms of life at different depths.

“These bacterial forms of life may be similar to microbes that existed on early Earth and thus provide a glimpse of how life evolved on this planet,” said Iliffe. “These caves are natural laboratories where we can study life existing under conditions analogous to what was present many millions of years ago.”

The research has been published in Hydrobiologia.