I started my own study on the posibility for life on Mars and concluded it is virtually inevitable that there is life. While there is micoscopic lifeforms and bacteria and the such around on the surface, what about underground? The temperature changes on Mars can be intence, ranging from Earth normal, to freezing cold, and with a thin atmosphere solar radiation and sudden temperature spikes. Mars is also extremely prone to massive sand storms that can batter the surface for days or even weeks. All of these things said, the surface of the red planet is all but inviting. On earth we see how in similar climates (as similar as they can get) life lives on underground. In some desert climates, where it is burning hot in the day and freezing at night, where sand storms tear at the earth and there is little if any rain, if one was to dig several feet underground, things like lungfish, certain types of reptiles, frogs even along with a wide asortment of insects can be found. If perhaps anywhere from several feet to roughly a mile under the surface of Mars the temperature stays consistant, without solar radiation and sand storms, then I am almost certain there is life. If the life is humanoid, then it would probably take form of a very hairy creature, to retain heat, probably short to navagate easier and would have excellent hearing. They would probably not need to eat much, and could retain moisture extremely effiecently. Of course, this proposed humaoid creature would have to be carbon based, and its cells based on liquid water, which of course every other race is not.