Mars Rock Varnish May Harbor Life

flewp points to this CNN story about yet another bit of evidence for life on the red planet, writing: "Basically, two Mars probes have found similiarities between Mars rocks and terrestrial rocks found in desert environments. Some real promising stuff for the supporters of martian life. Essentially, the organisms (if there) take metals from the atmosphere and oxidize them, and make them stick using secretions, leaving a varnish like surface on the rock." The evidence here is pretty thin (ha!), but interesting.