Strange DNA found in the desert offers lessons in the hunt for Mars life

Joel Achenbach in The Washington Post:

The Atacama Desert in Chile is just about the driest place on Earth. In spots, it looks a lot like Mars. But it’s not lifeless, even in the hyper-arid regions. Using state-of-the-art equipment to probe the desert rocks, researchers found bits of DNA from an intriguing mix of microbes.

Strikingly, 9 percent of the genetic fragments belong to organisms unknown to science, making them part of the “dark microbiome,” according to a report published Tuesday in the journal Nature Communications. These organisms are bacteria that are “so strange and different,” as the report puts it, that researchers could not identify any known relatives. “In almost half of the cases, the databases could not clearly say what we had in our hands,” lead researcher Armando Azua-Bustos, a microbiologist at the Center of Astrobiology in Madrid, told The Washington Post.

More here.