Jellyfish have been hiding a stunning secret about their ability to move throughout the water, and a recent study from Stanford engineers has finally cracked the code. According to a report from the LA Times, jellyfish bear a remarkable similarity to lampreys, which allows them to move swiftly and efficiently through the water.

The study found that rather than pushing themselves against the current, lampreys and jellyfish actually create zones of low pressure, forcing water around their bodies and propelling them forward.

The study was published in the journal Nature Communications and completely rewrites the chapter on jellyfish propulsion. According to senior author John Dabiri, a fluid dynamicist at Stanford, the findings present a whole new range of possibilities for studying jellyfish locomotion.

In general, animals move across terrestrial surfaces by pushing up against solid surfaces and propelling their bodies forward. This creates an area of high pressure between the animal’s foot and the ground, which results in forward movement.

Humans use this principle to both walk on land and swim in the water, using legs and arms to push against the water or ground. Researchers believed that this is how the majority of the animal kingdom moved, but the new study reveals a method that has not yet been observed by scientists.

The study compared jellyfish and lampreys, filling a tank with millions of tiny glass beads coated in silver. They outlined the tank with cameras and lasers, which traced the movement of the beads as animals swam through the tank. This would allow them to see different pressure gradients and figure out what forces were propelling the animals forward.

They found that jellyfish and lampreys bent their bodies to make a zone of low pressure, which caused water to rush in from in front of them and pull them forward.

The study’s findings are causing evolutionary biologists to seriously reconsider the way they visualize the progression of animal locomotion in the ocean.

A press release from Stanford outlining the study’s findings can be found here.