National Science Foundation
Media Tipsheet
February 14, 1994
Lynn Simarski

"This sandstone rock is alive," explains a new display in the Smithsonian Museum of Natural History's Constitution Avenue lobby. The chunk of calico-colored sandstone shelters cryptoendolithic microorganisms -- lichens and cyanobacteria -- growing in the tiny spaces between the rock's crystals. The rock was found in Antarctica's Dry Valleys, an ice-free area near the Ross Sea, by Florida State University microbiologist E. Imre Friedmann. The organisms are estimated to be 10,000 years old.

With the ambitious goal of "defining the absolute limits of life," Friedmann and NASA-Ames Research Center physicist Christopher McKay are monitoring an environmental transect in the Dry Valleys, which are also known unoficcially as the Ross Desert. The five sites range from barren, high peaks -- where nothing lives, but cryptoendolithic fossils abound -- to lower and milder locales that Friedmann calls the "crypto- endolithic Banana Belt." Small sensors inside the rocks monitor temperature, humidity, and light levels through the year, while conditions outside are also recorded. The researchers theorize that on Mars, given its own harsh environment, fossil traces of past life might also be found inside rocks. Friedmann works under the U.S. Antarctic Program, run by the National Science Foundation, and is also supported by NASA.