Michael Ray Taylor and his team penetrate up to a mile underground- lugging as much paraphernalia as an Everest assault team - in a quest to find the oldest life on the planet - organisms that could provide the key to life on earth. Taylor names these organisms 'dark life', and reports that they 'form complex ecosystems and food chains wholly independent of sunlight, photosynthesis, oxygen and other standard requirements for life as we know it'. Dark life resemble the headline-grabbing organisms, known as nanobacteria, discovered in a Martian meteorite in 1996, thereby adding to the debate on the possibility of life elsewhere in the solar system.