Life on Mars

I have been following Curiosity Rover on Twitter.
For those of you who don't know what that is, it is the unmanned science robot that is on the surface of the red planet looking to see if there ever had been Life on Mars.
It sends images and videos back to NASA, which are made available on line.
The photos show that the dust on the planet is not always as red as portrayed.
But if it was, and they did find signs of life, would it have looked like this?