Japanese scientists discover sea slugs that decapitate their own heads, grow new bodies

Japanese researchers have identified two species of sea slugs that have the ability to detach their own heads from their bodies, move around and grow entirely new bodies. 

Ecologists from Nara Women’s University in Japan published a study in the scientific journal Cell in which they identified two species of sacoglossan sea slug demonstrating the miraculous event. 

Researchers say that these animals were able to separate their heads from their hearts and body. 

The heads were then able to move around independently from its own body immediately after separation. 

Scientists say the wound from the separated heads would heal within a matter of days. 

The slug would feed on algae, and a new heart would be regenerated within a week. After around three weeks, the regeneration was complete, according to researchers. 

Video posted to YouTube (https://youtu.be/rtmtW_n09f4) on March 8 by Mitoh shows the head of a sea slug moving around as a lifeless body lies near it.

"We were surprised to see the head moving just after autotomy," Sayaka Mitoh of Nara Women’s University told Science Daily (https://www.sciencedaily.com/releases/2021/03/210308111922.htm).

"We thought that it would die soon without a heart and other important organs, but we were surprised again to find that it regenerated the whole body," she added.

This only occurred in young slugs, reports said. "The heads of older individuals didn’t feed and died in about 10 days," according to Science Daily. "In either case, the cast-off bodies didn’t regenerate a new head. But the headless bodies did move and react to being touched for several days or even months."