The results discovered by the Curiosity Rover are fascinating and suggest that our theories about life need to keep updating. This all suggests that we have evidence of the possibility of a little life on Mars but we're going to need a lot more Curiosity work before we actually know what happened ... at the moment we only have theories that might give us some ideas, but a lot of Curiosity evidence is that a very tiny form of life might have existed. I have always found Dr. Neil Shubin's writings about the creation of life to be very accurate about our life (our Inner Fish) and the possibility of life's creation in the Universe. Read his books if you want to learn how we started to exist on our planet.
This Mars evidence (Thank you El Reg) and all these theories about life's creation make me think that human life is wonderful, but very rare in the Universe. But I wonder if alien life exists, and is visiting us, then maybe they are fascinated too ... are those flying saucers Alien Rovers?