The revolutionary discovery in the 1970s of a thriving complex marine ecosystem around the hydrothermal vents of the Galapagos Rift on the ocean floor of the eastern Pacific forever changed our understanding of habitability showing that life could also arise and flourish in the complete absence of sunlight in conditions that were utterly toxic to any other life forms on Earth. (americaspace.com)
That brings up another point: cold weather humans were eating fructose and polyunsaturated fats in the relative absence of sunlight. (marksdailyapple.com)
Such rock reactions are exciting because they provide possible energy sources to fuel life in the absence of sunlight. (sciencedaily.com)