From Space.com WASHINGTON -- A pair of NASA scientists told a group of space officials at a private meeting here Sunday that they have found strong evidence that life may exist today on Mars, hidden away in caves and sustained by pockets of water. What Stoker and Lemke have found, according to several attendees of the private meeting, is not direct proof of life on Mars, but methane signatures and other signs of possible biological activity remarkably similar to those recently discovered in caves here on Earth. Such a find would of course be fantastic, albeit not terribly surprising. Scientists on our own dynamic world have found life in the most inhospitable places- from volcanic vents to the blackest depths of our oceans.