EPOW - Ecology Picture of the Week

Wind erosion on sandstone,
Capitol Reef National Monument, Utah USA

Explanation:  Your mission: scout the wind-ripped surface of Mars for life. Where should you begin?

NASA has sent many orbiters, rovers, and landers to Red Planet over the years, and has determined that water once ran on the surface and still occurs in polar regions.  But surface water is at best extremely rare at present.  So where do you look for signs of life?

One simple approach is to apply a trick used for decades by herpetologists and entomologists on Earth:  flip rocks!  It is beneath rocks where innumerable tiny organisms find shelter from the harsh world of wind, temperature extremes, desiccation, ultraviolet light, and ... perhaps on Mars .... also from cosmic radiation that would otherwise cook biotic forms.  

Earthly inhabitants of soil beneath rocks:
left: Campanotus carpenter ant ... right: Lithobius soil centipede
(click for larger versions)

Many tiny life forms hide beneath rocks in most environments on this globe ... so it may be a reasonable hypothesis (and very simple mechanical operation) to try it on Mars.  There may be an entire microscopic ecosystem awaiting discovery.

Also, rock surfaces that are more sheltered from the direct harsh environment might also be potential habitat for resilient life forms which, here on Earth, include bacteria, fungi, and lichens.   

Earthly life on rock surfaces:  crustose, foliose, and fruticose lichens.
Might there be some similar, rock-clinging life somewhere on Mars?
(click for larger versions)