A laboratory experiment simulating conditions on Mars found that certain terrestrial microorganisms called methanogens can survive in extreme Mars-like conditions involving low air pressure. While the work does not by any means suggest there is or ever was life on Mars, it illustrates one possible way primitive organisms might have once thrived on the Red Planet or could even exist below the surface today, according to Tim Kral of the University of Arkansas. Kral led the experiment and presented it to colleagues during a bioastronomy conference in Australia last month.