American Association for the Advancement of Science
Topsy-turvy algae tumble into line
Single algae cells called phytoplankton have a weird habit of spreading out in a thin film that can reach several kilometers across the ocean.
Phytoplankton are good swimmers that regularly move up and down in the water, and grouping together like this makes them easy targets ocean life looking for some algae to graze on. So, why do the phytoplankton freeze into place to make these films?
William Durham of MIT and his colleagues now have an answer. In a study appearing in the 20 February issue of the journal Science, the researchers explain how layers of ocean water flowing past each other can flip the organisms and send them tumbling around, unable to swim in a particular direction.
The cells then accumulate at the boundaries between the horizontally moving water layers.
These findings may help improve models of how and where phytoplankton accumulate in the ocean, which in turn may help address problems such as harmful algal blooms, damaged fisheries and ocean acidification.