Post #13921

Turritopsis Dornia: Immortal creature. This jellyfish cannot die of old age or illness If you were given a chance to live your life over again right now, what would you change? And in general, would you like to return to the beginning one more time, leaving behind age, fatigue and the consequences of the past years, or what? For us, this is rather a philosophical question, but there is a tiny jellyfish in the ocean, for which this is simply a biological mechanism. Meet Turritopsis Dornia, one of the few multicellular creatures known to science for which old age is not the end. These jellyfish are officially immortal. In scientific laboratories and articles on the Internet, Turritopsis is a real star. But in real life everything is much more prosaic. This tiny jellyfish measures just 4-5 millimeters in bell diameter - about the size of a fingernail. It is transparent, thin and completely weightless, because it consists of 95% water. Along the edge of the dome in adult individuals there are up to 90 thread-like tentacles, like an openwork veil. No poison or scary shapes. In the ocean, Turritopsis looks more like a random speck of dust than a creature capable of cheating death itself. These jellyfish were first found in the Mediterranean Sea. Today, their range has expanded a hundredfold - they can be found in the warm and temperate waters of the Pacific and Atlantic oceans. People helped them capture this huge area: when a large ship sails on the sea, water is sometimes pumped into it for stability. With everything that floats in it. And then, when stability is no longer needed, the water is poured back into the sea. Thus, small jellyfish swam thousands of kilometers and quietly captured new territories. And this is, perhaps, one of the most harmless introductions in the world, because turritopsis are harmless and, even despite their immortality, are unlikely to ever cause an environmental disaster. They feed modestly on plankton, but they are eaten by all and sundry. Turritopsis is considered immortal not because it never dies. If it is eaten by hungry fish, turtles or other sea creatures, life will naturally end. The trick is that the jellyfish does not age in the usual way for all other animals. The life cycle of ordinary creatures goes only in one direction: from youth to old age and, naturally, to death. But not for turritopsis. When an animal is damaged, encounters unfavorable conditions, or simply grows old, it does not die, but simply begins life again. This occurs through a process called transdifferentiation: specialized cells of an adult jellyfish change their function and turn into a different type of cell. To put it simply, usually in animals the cells “know” who they should be. Throughout the life of the organism, they never change their purpose. The muscle cell will help move throughout your life, the nerve cell will help conduct impulses, and the blood cells will carry oxygen. And it doesn’t matter whether the bod