Jellyfish build walls of water to swim around the ocean

Scientists have found that through a jellyfish’s pulsing gelatinous undulations, at least one species of jellyfish creates vortices that rotate in opposite directions. (Giovanni Paciello/Special to West Hawaii Today)

Locomotion through the seas can be arduous. Water is more viscous than air, and so underwater creatures must overcome strong frictional resistance as they swim.