If you were told that there was a creature capable of stealing organs from other organisms and then integrating them perfectly into its own body, you would immediately think of a B-series horror film. Yet, nature has realized this disturbing fantasy in the form of a small and peaceful sea snail. The elysia chlorotica It's not just any snail: this mollusc, just five centimeters long, has developed a capacity that defies every boundary between the animal and plant kingdoms. Which one?
When young, this small sea creature feeds on a brown algae called Coastal vaucheria, but instead of simply digesting it, it does something extraordinary: it steals millions of plastids (cell organelles that function like tiny solar panels) and stores them in the cells of its intestine, literally transforming into an animal-vegetable hybrid.
A solar thief
Incredibly enough, this snail has perfected the art of biological theft. It is, it must be said, the elysia chlorotica He chose his victim carefully: the algae Coastal vaucheria It has no walls between adjacent cells, it is basically a long tube filled with nuclei and plastids. When the snail makes a hole in the outer cell wall, it can suck out the entire contents and collect all the algal plastids in one go. A perfect robbery, planned by evolution over millions of years.
This is a remarkable achievement because it is highly unusual for an animal to behave like a plant and survive solely through photosynthesis.
These are the words of Debashish Bhattacharya, senior author of the study (that I link to you here) and professor in the Department of Biochemistry and Microbiology at the Rutgers University-New Brunswick.
The idea that an animal can literally “go green” and survive on light like a plant challenges our most basic understandings of the separation of biological kingdoms.
Elysia Chlorotica, beyond simple storage
You might wonder if the snail is simply storing these plastids as a food reserve, much like camels do with their humps of fat. But the study published in the journal Molecular Biology and Evolution proves that it is not so. The snail actively maintains these stolen plastids by protecting them from digestion and activating its own genes to utilize the products of algal photosynthesis.
The most surprising thing is that, while the plastids survive, the algal nuclei sucked up along with them do not last long. And here lies the real mystery.: Scientists still don't understand how the Elysia Chlorotica keep plastids functioning for months without the nuclei that normally control their function.
Towards perpetual green energy
What makes the elysia chlorotica so interesting is not only its peculiar biology, but also the potential applications in the field of artificial photosynthesis. The broader implication is revolutionary: If we could figure out how the snail keeps these isolated plastids functioning, we could theoretically exploit isolated plastids for eternity. as “green machines” to create bioproducts or energy.
The study, conducted by a team of researchers from the Rutgers together with colleagues from the universities of Queensland, Maine and Connecticut, opens up fascinating scenarios. The current paradigm is that to produce green energy we need the whole plant or algae to operate the photosynthetic organelle. But this snail shows us that it doesn't have to be that way.
Looking at this little green creature swimming peacefully in the cold waters of the Atlantic, I can't help but think that, sometimes, the most innovative solutions to our energy problems might already be there, hidden in plain sight, in the ingenuity of natural evolution. It's just a matter of knowing how to look at the light (so to speak) with different eyes.
