Scientists have discovered the ultimate case of resuscitation: some headless sea snails can regain control of the heart and the whole new body.
This “wonder of nature”, reported in the Biology Journal on Monday, could ultimately help scientists better understand and cope with the regeneration of human tissues.
Biology researcher Sayaka Mitoh said he prefers to study Japanese sea snails because they are small, beautiful and exotic. They can also synthesize photosynthesis briefly, like plants drawn from the sun.
One day in the lab, she saw something strange: a sea snail had crumbled on its own and its head was moving and living. A couple did the same thing later in a study of current biology.
So Yoichi Yusa, a doctoral student and professor of aquatic ecology at Nara Women’s University, tried it by beheading 16 sea snails. Six of the creatures began the resurrection, three successful and surviving. One of the three also lost and regained his body twice. Two different species of Japanese sea snails performed this revival trick.
Other creatures cast out body parts when needed, such as when a lizard throws its tails to move away from a predator, in a biological phenomenon called autotomy.
“We think this is the most extreme case of ot totomi,” Yusa said. “Some animals could automate their legs or appendages or tails, but no other animal laid their whole body.”
Scientists thought that this relatively large animal – a species of sea snail that could grow up to 6 inches (15 cm) tall – could not live without a heart to put blood and nutrients into the brain, said Canadian marine biologist Susan Anthony. Which was not part of the study.
But the only thing that makes this species stunning is the one that helps pull the trick, Anthony and Yusa said.
When these sea snails eat certain types of algae, they can photosynthesize their food from sunlight and oxygen like plants for about 10 days, Yusa said. What is probably happening after the beheading is a major operation like vegetation, he said. It changes the shade of greenery and gets its energy from oxygen and sunlight. The fact that it gets smaller helps, he said.
Mitoh and Yusa said the species has developed this achievement as a way to fight parasites.
Humans can learn something useful from sea creatures, many scientists said. Of particular interest is the fact that these sea snails are more complex than flatworms or other species known for regeneration, said Nicholas Curtis, a professor of biology at the University of Maria, who was not part of the study.
“It is inherently a wonder of nature, but understanding the molecular mechanisms underlying it can help us understand how our cells and tissues can be used to repair damage,” Curtis said in an email.
