WOODS HOLE, MASS.In another blow to the "Everything is Everywhere" tenet of bacterial distribution in the ocean, scientists at the Marine Biological Laboratory (MBL) have found "bipolar" species of bacteria that occur in the Arctic and Antarctic, but nowhere else.
And, surprisingly, they found even fewer bipolar species than would turn up by chance if marine bacteria were randomly distributed everywhere. "That suggests that there are forces that are limiting the dispersal of bacteria in the ocean," says Linda Amaral-Zettler, a scientist in the MBL's Bay Paul Center and faculty member in the Brown-MBL Partnership.
The discovery is reported this week in Proceedings of the National Academy of Sciences, with Amaral-Zettler as corresponding author.
"Our study shows that marine bacteria are not just homogenous populations in the ocean. They are more selective than that. Different bacteria prefer certain temperatures, levels of nutrients, light and salinity, " Amaral-Zettler says. "Understanding their distribution is really important because bacteria play crucial roles in the ocean ecosystem services we rely upon, such as providing food stocks, and in climate. As our environment changes, and temperatures become warmer, we have to pay attention to shifts in bacterial distributions, as well as those in animals and plants."
The study is one of many born from the gigantic database on marine microbes created during the International Census of Marine Microbes (ICoMM), a part of the Census of Marine Life. It also contains data from MIRADA-LTERS (Microbial Inventory Research Across Diverse Aquatic Long-Term Ecological Research Sites).
Over a six-year period (2004 to 2010), ICoMM scientists from many nations collected water samples and, crucially, related environmental data from a broad range of marine ecosystems, from open ocean to undersea volcanoes, densely populated coastlines to polar seas. MIRADA-LTERS also contri
|Contact: Diana Kenney|
Marine Biological Laboratory