Scientists uncover vast differences in Earth’s polar ocean microbial communities

ANN ARBOR-An international team of scientists, including a University of Michigan graduate student, has demonstrated that a clear difference exists between the marine microbial communities in the Southern and Arctic oceans, contributing to a better understanding of the biodiversity of marine life at the poles. The most comprehensive comparison of microbial diversity at both of Earth's polar oceans showed that about 75 percent of the organisms at each pole are different. This insight sheds light on newly recognized biodiversity patterns and reinforces the importance of studying Earth's polar regions in the face of a changing climate. And it highlights the need for further research on the impacts of sea ice, seasonal shifts and freshwater input in both regions. "We believe that significant differences in the environmental conditions at each pole and unique selection mechanisms in the Arctic and Southern oceans are at play in controlling surface and deep-ocean community structure," said Alison Murray, leader of the international team and an associate research professor at the Desert Research Institute in Reno, Nev. The team reported its findings online Monday in the Proceedings of the National Academy of Sciences. Kevin Bakker, a graduate student in the U-M Department of Ecology and Evolutionary Biology, is a co-author of the PNAS paper.