High-Speed Video Shows Sea Butterflies 'Flying' Like Insects Through the Water


Snails aren't exactly known for being graceful creatures, but the way this species of sea snail gets around is unique. Where a land-based snail’s foot would be, the aptly nicknamed “sea butterfly” has a pair of wing-like structures it uses to flutter through the water. According to New Scientist, video has been recorded for the first time of the snail in motion that shows it moving in water similarly to how an insect flies in the air.

In their new study published in the Journal of Experimental Biology [PDF], scientists at the Georgia Institute of Technology detail how they were able to capture this phenomenon on tape. The team released 20 sea snail specimens into a tank of salt water, hoping that the 3-millimeter creatures would pass in front of one of the four high-speed cameras inside.

The movements they were lucky enough to capture revealed something surprising about the snails. Instead of using their appendages like paddles to drag them through the ocean, like most zooplankton do, the sea butterflies flapped their wings to produce lift. The familiar figure-eight pattern the snails demonstrated is remarkably similar to what’s seen in fruit flies and other insects, even though the species are separated by 550 million years of evolution.

Because sea snail wings flap at a much slower pace than the wings of insects like fruit flies—about five beats per second compared to 200 beats per second—further studying this behavior could help scientists better understand how insects fly. Brad Gemmell, an assistant professor at the University of South Florida who studies swimming in sea creatures, believes the mechanism could be used to design new micro flying vehicles. 

[h/t New Scientist]

Header/Banner images courtesy of New Scientist via YouTube