The latitudinal gradient in species diversity is one of the most celebrated and best studied global patterns, even inspiring naturalists like Alfred Russel Wallace. However, what appears true for plants and animals may simply not hold for bacteria. Queen's University professor Paul Grogan, postdoctoral fellow Haiyan Chu, and collaborators from the University of Colorado investigated species composition and genetic divergence of soil bacterial communities in 29 arctic locations scattered across Canada, Alaska, Iceland, Greenland and Sweden.The researchers found that each soil sample not only contained thousands of bacterial types, but that about 50% were unique to each. Perhaps more surprising still was the observation that geographic proximity was not a good predictor of community composition, but rather that soil acidity irrespective of distance between samples best predicted the pool of bacterial types found. These findings will be published in the journal Environmental Microbiology. For more information please see the Queen's press release | here |.