Newly discovered single-celled creatures living deep beneath the seafloor have provided clues about how to find life on Mars. These bacteria were discovered living in tiny cracks inside volcanic rocks after researchers perfected a new method cutting rocks into ultrathin slices to study under a microscope. Researchers estimate that the rock cracks are home to a community of bacteria as dense as that of the human gut, about 10 billion bacterial cells per cubic centimeter.
— Read on www.sciencedaily.com/releases/2020/04/200402080506.htm