It’s true, men really are from Mars The Guardian

Comment: Nasa landed two Viking spacecraft on the Martian surface with the specific aim of searching for signs of biological activity. Not so much as a bacterium was found. The surface of Mars appeared to be a freeze-dried desert, utterly hostile to any form of life. Today this pessimistic assessment seems too hasty. I believe not only that Mars has harboured life, but it may actually be the cradle of life. This conclusion arises because of the recent discovery that our biosphere extends deep into the bowels of the Earth. Microbes have been found thriving at depths of several kilometres, inhabiting the pore spaces of apparently solid rock. Genetic studies suggest these deep-living organisms are among the most ancient on the planet. They are, in effect, living fossils.