A dark realm far beneath the Earth's surface is a surprisingly rich home for tiny worms and "zombie microbes" that may hold clues to the origins of life, scientists said on Monday.
The scientists also found viruses deep underground. Unlike those at the surface, those in the energy-poor subsurface typically insert their genes into microbes without seeking to reproduce aggressively, apparently waiting for better conditions.
"This role of virus as parasite, as mutualist, and as a sharer of information through gene transfer may be a fundamental underpinning of life in the deep subsurface," the book suggests.
By Environment Correspondent Alister Doyle.