MAR 09, 2021 2:57 PM PST

Sea Slug Shows Extreme Case of Regeneration

WRITTEN BY: Tiffany Dazet

Some of the most interesting—and possibly strangest—scientific discoveries happen by accident. According to the New York Times, Sayaka Mitoh, a Ph.D. candidate at Nara Women's University in Japan, was studying the life history of sea slugs when she stumbled upon something bizarre.

One of her captive-raised sea slugs had somehow been decapitated, and the head seemed to be moving around and eating. Then, as the Times reports, she realized that the slug itself initiated the decapitation. While self-amputating limbs are not unheard of for some organisms, the self-amputation of an entire body had not yet been observed. The video below from Live Science summarizes this unique discovery.

As Mitoh stated to the Times, "I was really surprised and shocked to see the head moving." She also says that she expected it to die quickly without major organs needed to survive. Not only did it survive, but the Times reports that it regenerated most of its body within three weeks.

This random incident encouraged Mitoh to investigate this extreme form of self-amputation. The results of this work were published earlier this week in Current Biology. According to the study, the two species of sacoglossan sea slug (Elysia marginate and Elysia atrovirdis) undergo "a new type of extreme autonomy." They shed their main body and regenerate a new one—including the whole head. Additionally, the study reports that the shed body does not regenerate a head. According to the Times, some detached bodies remained reactive to stimuli for months until they finally decomposed.

The New York Times reports that the head wound where the detachment occurred healed within one day. The heart regenerated in about one week, and most sea slugs completely regenerated within three weeks. Additionally, these particular sea slugs can sustain themselves through photosynthesis, which likely allows them to survive without the rest of their vital organs for extended time periods.

Because this process occurs too slowly to be a predator defense mechanism, the Times reports that the team suspects the body detachment occurs if the slug has a parasitic infection. However, only one of the two species studied had parasites.

While this study confirmed these two species' extreme regeneration capabilities, the exact mechanism of this process is yet to be determined. The Times reports that Mitoh is hopeful that this process could lead to advancements in regenerative medicine.

Sources: New York Times, Current Biology, Science News

About the Author
  • Tiffany grew up in Southern California, where she attended San Diego State University. She graduated with a degree in Biology with a marine emphasis, thanks to her love of the ocean and wildlife. With 13 years of science writing under her belt, she now works as a freelance writer in the Pacific Northwest.
You May Also Like
SEP 07, 2021
Plants & Animals
All dogs may be descended from the same 23,000-year-old Siberian ancestor
SEP 07, 2021
All dogs may be descended from the same 23,000-year-old Siberian ancestor
New research suggests that all modern dogs are descended from the same 23,000-year-old Siberian ancestor
SEP 19, 2021
Microbiology
How a Bacterial Molecule Turns Plants to 'Zombies'
SEP 19, 2021
How a Bacterial Molecule Turns Plants to 'Zombies'
Some parasites are known to turn their hosts into mindless servants, or zombies, that only function to serve the parasit ...
SEP 28, 2021
Microbiology
A 24,000-Year-Old Rotifer From the Siberian Arctic is Alive & Thriving
SEP 28, 2021
A 24,000-Year-Old Rotifer From the Siberian Arctic is Alive & Thriving
This image by Michael Plewka shows a very tough old rotifer.
SEP 28, 2021
Neuroscience
Is morality all about taste?
SEP 28, 2021
Is morality all about taste?
Researchers establish inhibited tongue motor capacity in response to moral transgression
OCT 25, 2021
Cancer
Could Pomegranates Play a Role in Cancer Prevention or Treatment?
OCT 25, 2021
Could Pomegranates Play a Role in Cancer Prevention or Treatment?
Pomegranate (Punica granatum L) is an ancient fruit grown primarily in western Asia and Mediterranean regions.  ...
OCT 14, 2021
Plants & Animals
Urbanization A Key Factor In Insect Population Decline
OCT 14, 2021
Urbanization A Key Factor In Insect Population Decline
In recent years, the number of insects in a given ecosystem (biomass) and the number of insect species (biodiversity) ha ...
Loading Comments...