Dolphins are famous for their speed and agility in the water, but what exactly allows them to swim so effectively? Scientists have been asking this question for years, hoping to learn how to optimize propulsion in fluids from these elegant creatures.

When a dolphin swims, it flaps its tail up and down in a kicking motion. This motion pushes water backward, generating a turbulent flow filled with swirling currents of many different sizes. Until now, it has been difficult to determine how these complex motions conspire to propel the dolphin forward.