Scientists have discovered a jellyfish which can live forever. The Immortal Jellyfish known scientifically as Turritopsis dohrnii is now officially known as the only immortal creature. When the medusa of this species is physically damaged or experiences stresses such as starvation, instead of dying it shrinks in on itself, reabsorbing its tentacles and losing the ability to swim. It then settles on the seafloor as a blob-like cyst. In response to physical damage or even starvation, they take a leap back in their development process, transforming back into a polyp. In a process that looks remarkably like immortality, the born-again polyp colony eventually buds and releases medusae that are genetically identical to the injured adult.
The secret to eternal life, as it turns out, is not just living a really, really long time. It’s all about maturity, or rather, the lack of it. The immortal jellyfish propagate and then, faced with the normal career path of dying, they opt instead to revert to a sexually immature stage. Simply explained, yes. Here is what actually happens. When the medusa the immortal jellyfish dies, it sinks to the ocean floor and begins to decay. This regeneration process has now been found in around five species of jellyfish.
Immortal jellyfish can still die if they become prey to other animals. Their bodies are miniscule, so they are easy prey for a variety of hungry creatures. Still, their specialized cells make it possible for them to revert to their juvenile stage when they experience damage or stress. If they avoid predation, they have the potential to live forever. The jellyfish Turritopsis nutricula is biologically immortal and could, under ideal conditions, live for 1000s of years. After sexually reproducing, this jellyfish can revert back to the immature polyp stage (back into a “child”). The jellyfish can still die due to predation, but aging is not a problem for it.
What happens with this particular species is that it can transform from jellyfish medusa (the jellyfish part) back to the polyp (the sea anemone-looking part). Now in one sense, this is like an adult going back to a baby, or a butterfly turning back into a caterpillar. So it’s getting younger right, which means it can last forever! But hold on. It’s getting younger in terms of shape, but that doesn’t tell you anything about the animal’s age on the level of its DNA. Its easy to imagine a situation where the total lifespan of the animal is not extended, it’s just able to swap back and forth from medusa to polyp as circumstances require.
What’s the oldest immortal jellyfish?
There is a special jellyfish species that scientists say may be immortal. Turritopsis dohrnii, dubbed ‘the immortal jellyfish’, can regenerate old cells and revert to a younger stage of life after injury, illness, hunger or aging. This regeneration happens through a process called ‘transdifferentiation’.
The jellyfish falls to the ocean floor where the adult medusa reverts to a polyp form. The polyp creates new, genetically identical cells. Theoretically, this renewal process enables the jellyfish to live indefinitely until a predator like a turtle or fish eats it.
Despite having a huge party trick, immortal jellyfish average only three millimeters in diameter. The born-again polyp colony eventually buds, releasing medusae identical to the formerly injured adult.
While the jellyfish’s immortality skill fascinates us, it lives an ephemeral existence. Many creatures like to eat it. Its tiny size makes it barely visible in the ocean. Any predator — a larger jelly, sea anemone, shark or penguin — would find it a tasty treat.
Can immortal jellyfish sting you?
The immortal jellyfish is typically found in temperate and tropical oceans. Originally from the Pacific, this jellyfish has spread across the world. This happened due to ballast water discharge. The immortal jellyfish primarily feeds on plankton, fish eggs and smaller sea creatures. It uses its tentacles to hunt. Despite having predators like sharks and sea turtles, the immortal jellyfish’s stings are not lethal to humans.
What makes the Turritopsis dohrnii jellyfish unique is its ability to revert to an earlier developmental stage. This happens when it is injured or threatened. This process of reversing its lifecycle is called “transdifferentiation.” This was never before observed in the animal kingdom. In the mid-1990s, skeptical students led by their professor studied the jellyfish. Through experiments, they proved the jellyfish become polyps when stressed. And that they can repeat this process over and over.
While immortal, the jellyfish can easily be killed by predators. Its tentacles contain stinging cells that can be painful. But the immortal jellyfish is tiny, barely visible at 4.5 millimeters wide. If provoked, it will sting in defense. Although immortal, the jellyfish still dies from old age after completing its natural life cycle. It also dies from diseases or environmental changes. But unlike other animals, it doesn’t perish due to old age alone. This makes the jellyfish biologically immortal. No other known species possesses this trait.
Can immortal jellyfish get eaten?
They might be ‘kind of immortal’, but the immortal jellyfish are not impervious to all threats. They can be eaten by bigger creatures, or get killed. The jellyfish has skipped to an earlier life stage to begin again.
In the medusa stage, immortal jellyfish can move. In the polyp stage, they are also somewhat motile. We know that jellyfish can catch and eat prey in all stages of their life. Though it isn’t advanced, jellyfish display behaviors that prove they have senses.
The nutrition of immortal jellyfish consists of plankton, fish eggs, larvae, and other tiny sea creatures. It is a unique mechanism called transdifferentiation that allows this particular jellyfish to regenerate. Immediately noticeable due to their colorful presence, jellyfish can be found in seas all over the world. They are also one of the oldest multi-organ animals, inhabiting our planet for 500 million years.
It is highly possible that immortal jellyfish survive ocean crossings thanks to their ability to reverse their life cycle when they experience stresses, such as a lack of food. From a study of T. dohrnii around the world, researchers found that immortal jellyfish in tropical regions had only eight tentacles, whereas those in more temperate waters, could have 24 or more.
What kind of food does the Turritopsis dohrnii eat? Turritopsis dohrnii are a carnivorous species that commonly feed on zooplankton. Their diet mainly consists of plankton, fish eggs and small mollusks.