0117 GMT May 21, 2019
To find out, they built a fleet of mini underwater robots designed to mimic plankton existence, UPI reported.
For now, there are 16 of the miniature autonomous underwater explorers, or M-AUEs, but someday scientists could deploy thousand of the devices.
Each robot is roughly the size of a grapefruit and is outfitted with sensors to measure temperature and current.
The bots constantly swim up and down to maintain their position just beneath the surface. Like real plankton, they let currents do most of the work of transportation.
Researchers designed the swarm of bots to help them understand how and why plankton move and accumulate as they do.
Scientists were specifically keen on figuring out why plankton tend to concentrate in 'patches' just beneath the ocean surface, only later revealing their presence during red tides and similar phenomena.
"These patches might work like planktonic singles bars," Peter Franks, a biological oceanographer at Scripps, part of the University of California, San Diego, said.
Franks was hopeful the plankton-mimicking bots would confirm a mathematical theory he developed two years ago to describe plankton patches.
Franks' theory posited that internal waves — ocean waves beneath the surface — push groups of plankton into dense patches.
The early returns supported his hypothesis.
Data returned by the bots showed currents generated by internal waves encouraged the formation of tightly knit patches, while wave crests had a dispersion effect. Researchers published the initial findings in the journal Nature Communications.
"This is the first time such a mechanism has been tested underwater," said Franks.
Researchers believe their technology could be used to study a variety of other dynamic underwater systems.