Five long-lived species on Earth
On Earth, there are five incredibly long-lived creatures that humans can hardly imagine, some even possessing the ability to live forever.
5th Place: Galapagos Tortoise
The Galapagos tortoise is currently the largest land tortoise in the world, with a body length of up to 1.2 meters and weighing around 300kg. Their average lifespan is over 150 years. They move very slowly but are incredibly resilient, able to survive for dozens of months without food or water. However, due to rampant hunting by humans, they were once on the brink of extinction. To save the species, a male tortoise named Diego was sent to Santa Cruz Island to live and reproduce with six female tortoises. Diego's exceptional reproductive capabilities led to over 800 offspring in just 50 years, directly rescuing this nearly extinct population.
4th Place: Bowhead Whale
This is the longest-living mammal in the world, with a lifespan that can exceed 200 years. Living primarily in the cold Arctic Circle, they have a thick layer of subcutaneous fat, which makes them slow swimmers. The extremely low temperatures also result in a lower metabolic rate, reducing cell damage and the aging process. However, since the 18th century, these slow-moving bowhead whales have been a prime target for hunters, rich in valuable oil and baleen. Coupled with their slow reproduction cycle, their population has dramatically decreased. Today, there are fewer than 6,000 bowhead whales left in the world, making them an endangered species.
3rd Place: Greenland Shark
This is the longest-lived vertebrate known, with an average lifespan of over 400 years, primarily living in the waters near the North Atlantic. In 2017, Danish biologists discovered a Greenland shark that had lived for an astonishing 517 years. Despite living in the deep sea at around 2000 meters, these sharks move very slowly, with a top speed of only 70 cm per second when hunting. Their slow metabolism and growth rate have earned them the nickname "the shark forgotten by death."
2nd Place: Arctic Clam
This ancient deep-sea species dates back to the Late Cretaceous period. Living in the cold deep sea, their cells metabolize extremely slowly, making them very long-lived, with an average lifespan of over 500 years. In 2006, scientists captured a giant Arctic clam in the North Atlantic and estimated its age to be 405 years. Named "Ming" after the Chinese dynasty when it was born, further analysis revised its age to 507 years. Unfortunately, in an attempt to study its longevity, scientists opened its shell, which ended the clam's life at 507 years old.
1st Place: Turritopsis dohrnii (Immortal Jellyfish)
This is the longest-living creature known to humans, with the remarkable ability to revert to a juvenile state, effectively breaking the natural cycle of birth, aging, and death. As carnivorous cnidarians, Turritopsis dohrnii are about 5mm in diameter. They grow slowly in waters around 20°C, taking a month to mature. When they approach the end of their life, they initiate a special process of transdifferentiation, transforming into a cyst and then back into their most primitive form, a polyp, from which a new jellyfish with the same DNA grows. Theoretically, this process is unlimited, allowing them to achieve virtually infinite lifespan through repeated sexual reproduction and transdifferentiation. Aging seems non-existent to them, and time is like a toy at their disposal. As long as they avoid predators, they can, in a sense, achieve immortality. With scientific progress, researchers are studying the genetic code of Turritopsis dohrnii to find clues to delay aging. These jellyfish, unchanged since the Cretaceous period, seem to be forgotten by nature, lonely yet helpless.