Scientists guided herds of "sea monkeys" with a laser to determine how zooplankton migrations affect global ocean currents.
These brine shrimp vertically migrate in large groups that swim closer to the surface in the darkness of night and dive deeper when the Sun comes up, the American Institute of Physics reported.
Researchers demonstrated how this pattern of movement affects water currents, which could in turn influence global circulation patterns on a scale comparable to wind and tides.
Since brine shrimp (sea monkeys) display phototaxis (the tendency to move towards light) researchers used lasers to herd the small crustaceans in a water tank to induce a vertical migration pattern. To see how these movements affected the current the team mixed silver-coated glass spheres into the water and captured the changes in their distribution on high-speed camera.
The team found when two or more brine shrimp swim in close proximity to each other they create eddies that trigger "powerful swirling fluid forces" which could affect global circulation patterns. These patterns are important because currents are responsible for distributing nutrients, salts, and heat throughout the ocean.
"This research suggests a remarkable and previously unobserved two-way coupling between the biology and the physics of the ocean: the organisms in the ocean appear to have the capacity to influence their environment by their collective swimming," researcher John Dabiri said.
In the future the researchers hope to replicate the experiment in a tank where the water density increases at lower depths, which is closer to the conditions within the ocean.
"If similar phenomena occur in the real ocean, it will mean that the biomass in the ocean can redistribute heat, salinity and nutrients," Dabiri said.
Small organisms make up the vast majority of oceanic biomass, so researchers estimate their movement as a whole could contribute a trillion watts of power to the ocean.
The findings were published in a recent edition of the journal Physics of Fluids. The study was conducted by Dabiri and Monica Wilhelmus of the California Institute of Technology .
