If microbial life is found on Mars, will it be native to the planet or something carried there from Earth? Either way, will it be safe to return samples of such organisms to Earth? Astrobiology, the search for life elsewhere, says a University of Illinois microbiologist, is making us look a lot closer at microbial life on Earth — how it adapts and its relationship to emerging infectious diseases. “Even if we don’t find life on other planets, we are learning a lot about life on the Earth, particularly microbial life,” Abigail Salyers said in an interview about her speech Friday, Feb. 15 at the annual meeting of the American Association for the Advancement of Science in Boston, Mass. She challenged scientists to consider far-reaching possibilities in a talk titled “Are There Medical Implications of Geomicrobiology?”