The severed head of a sea snail reconstructed the rest of its body

The severed head of the marine nudibranch snail Elysia cf. marginata has regenerated and reconstituted the rest of its body at an express pace.

The whole situation is described in a scientific article published in the journal Current Biology. It turns out that the severed head of a nudibranch snail regenerated the rest of its body in just two to three weeks.

-- Advertisement --

Incredibly and worth noting, the decapitated torso was also able to survive for as long as several months, until putrefactive processes began to progress and decomposition of the body took place.

The study was carried out by a team of researchers from Nara Women’s University in Japan, who bred a species of Sacoglossan sea snail (Elysia cf. marginata) to investigate its ability to conduct photosynthesis. At that time, a still-living severed head was discovered and observation began.

It is nothing new that some animals are capable of autotomy, i.e. discarding a body part when the animal is in danger and getting rid of a limb or tail could help it escape. However, in this case, when the researchers tried pinching and poking another group of snails to mimic a predator attack, none of the animals responded by getting rid of any body part.

It was only after an extensive study in which the team observed 160 nudibranch snails every day, which included individuals bred in the lab as well as wild ones caught in the wild, that they discovered that 5 of the 15 bred in the lab and 3 of the 145 wild ones had shed their heads, while 39 wild snails had discarded smaller body parts such as the tail.

Further research also revealed that some of the nudibranch snails collected in the field had internal copepods, parasitic crustaceans – including all 42 that had cut off part of their bodies.

We believe that at least this particular species of sacoglossans autotomizes to remove internal parasites that inhibit their reproduction,” said Sayaka Mitoh, a scientist with the Nara Women’s University research team

The researchers suspect that stem cells play a key role in the whole process of regenerating the discarded body. The team is currently conducting research on other snail species in an effort to learn more about their ability to regenerate.

Photo: Sayaka Mitoh