New studies suggest the beginnings of life on this planet could have occurred deep underground, the Independent reports.
Researchers have found microbes up to 3.1 miles below the Earth's surface — tiny organisms that are almost exactly the same on opposite sides of the planet. That points to a possible common ancestor about 3.5 billion years ago, which is when earthly life began, the paper explains.
Scientists pulled such microbes from fissures in rocks as widespread as North America, Japan, Europe, South Africa, and even, according to Red Orbit, deep hydrothermal vents in the Caribbean.
The samples were more than 97% identical, or practically the same species, according to researcher Matt Schrenk, who notes that some may "live as deep as (6 miles) into the Earth."