They look like open pea pods with a bright sheen, sea slugs Elisis cf. marginalized i Elysia atroviridis they are not your average gastropods. First, they are members of sacoglossa, a slug clade known to take algae from marine plants and integrate the chloroplasts of this alga their own cells, which allows them to obtain energy from sunlight. These two species of slugs are also capable of extreme regeneration; they tin cut off his head and grow completely new bodies.
New research published today in Current Biology describes this incredible feat of autotomy or self-amputation. (It is worth noting that the bodies do not generate any new ones.) The discovery was made in Yoichi Yusa’s laboratory at Nara Women’s University in Japan, which sea slugs from eggs to adulthood from generation to generation to better understand these viscous creatures.
Sayaka Mitoh, a university biologist and lead author of the recent article, stumbled upon the good intention of dismembering slugs when she came across an individual in the lab whose head was no longer connected to her pickled milled body. . But his head was still moving.
“We hadn’t thought they would perform such an unusual autotomy,” Mitoh said in an email. “This finding was completely a coincidence.”
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Once the team found a self-taught individual, they set out to investigate why, and precisely, how this breakup occurred. These observations included attempts to induce self-decapitation, mimicking the kind of shallow pebbles a marine predator would make in the slime in the wild (perhaps, they guessed, the separation of the slug from its body was similar to a fighter jet pilot using an ejector seat).
The investigators he tied a nylon cord around the place where the slug’s head met his body, where it looked like the slug was predisposed to split the body-cranial body. They did it lightly enough, more like a tie too tight than a suffocating agent, but slugs don’t have respiratory systems like vertebrates do, so there are no grains..
While the true nature of autotomy remains unknown, the team was able to induce autonomy in all but one tragedy. in one day. In the newspaper, Mitoh’s team suggested that autotomy could occur in the wild Elysia atroviridis because the slug is often loaded with planktonic parasites, perhaps leaving behind a parasitic body to make a new one it is the easiest way to deal with the infestation. The researchers found that slugs could spend days without their heart (located in the (just below the break plane), and, along a couple weeks, the new bodies were almost full size. In the diary, the team argued that slugs could come out without their bodies surviving purely photosynthetic capabilities.
“While living a few days without a heart may seem impossible from our human perspective, these animals really breathe through their skin and don’t have gills completely,” he said. Elise Laetz, expert in photosynthesizing sea slugs at the University of Groningen in the Netherlands who is not affiliated with the new to study. “I’m not surprised they can endure a heartless week of pumping oxygenated hemolymph (like invertebrate blood) around the body while they regenerate a new one.”
Laetz said in an email which seemed like the idea of photosynthesis as rations less likely, as many of the mechanisms of kleptoplasty (this unique ability to take seaweed chloroplasts and use them take advantage of them solar energy) are in the body, not the head.
“Chloroplasts are stored in the digestive gland of the slug, which is highly branched and located mainly in the body of most sacoglossan species. When the slug self-automates its body, it releases most of the chloroplasts and therefore most of the energy it could get from these chloroplasts, “Laetz said.” I think slugs are more likely to feed regeneration. feeding directly after it automates its body, as the authors observed. “
Much more research is needed to better understand how these creepy little slugs exercise existence without the help (or obstacles) of most of their body shape. TNew observations suggest that there are many more questions to order themand animals.
“We want to study whether other species of sacoglossans have this ability, to study the evolutionary pattern and process of this extreme autotomy and regeneration,” Mitoh said. “It is also worth studying the function of autotomy. In addition, we will further explore the mechanisms underlying this phenomenon at the tissue and cellular level. “
Maybe not have the charisma of a “corgi ” giraffe or the DNA zany of a platypus, but the photosynthesizer, self-decapitated sea slugs inside sacoglossa deserve the same attention. Headless bodies will continue to be investigated and headless bodies even more so.
“Observations such as those presented in this article highlight the need for fundamental scientific research on all branches of the tree of life,” Laetz said. “You never know when an animal as harmless as a sea slug has a capacity that could lead to advances in applied research.”