"Finding a new reservoir of water on Mars--even if it's frozen mud--inevitably raises the question of life. Intriguingly, the combination of a dry top layer and an ice-laden lower layer exists today in the Dry Valleys of Antarctica. There, despite the cold and dry conditions, lichen grows. Mars could turn out be the home of little green plants."

Little green plants? Maybe, but some people might think a "little green plant" is a couple inches high instead microscopic.

I wonder how the "Dry Valleys of Antarctica" would really compare to the "wettest" locations found on Mars (not considering the higher radiation and lack of atmospere).