Greenland Shark – 500 Years: The Greenland shark is Earth’s longest-living vertebrate. Research suggests lifespans beyond 400 years, with one individual possibly reaching 512 years. These sharks thrive in Arctic deep waters. (Image: Canva) Red Sea Urchin – 200 Years: Red sea urchins, found in Pacific waters, can live over 200 years. They show almost no signs of ageing and remain fertile throughout their lives. (Image: Canva) Immortal Jellyfish (Turritopsis dohrnii): Nicknamed the “immortal jellyfish,” it can reverse its life cycle, turning from adult back to polyp repeatedly. This process makes it biologically ageless, though predators can still kill it. (Image: Canva) Hydra – The Eternal Creature: Hydras regenerate endlessly with stem cells, showing no signs of ageing. Though vulnerable to predators, in safe conditions, these tiny invertebrates could live forever. (Image: Canva) Tubeworms – 300 Years: Found on the seafloor, tubeworms feed through symbiotic bacteria. Escarpia laminata species can surpass 300 years, surviving with slow metabolism and almost no predators. (Image: Canva) Glass Sponge – 11,000 Years Old: Glass sponges form colonies with skeletons resembling glass. Some species, like Monorhaphis chuni, have been dated to around 11,000 years, making them among the oldest animals alive. (Image: NOAA's National Ocean Service) Black Coral – 4,000 Years: Deep-sea black coral may look like rock, but it’s made of tiny polyps. Radiocarbon dating shows specimens in Hawaii are over 4,200 years old. (Image: Anthony Montgomery/NOAA's National Ocean Service) Ocean Quahog – 507 Years: The Arctica islandica clam grows slowly in cold Atlantic waters. One, nicknamed Ming, lived 507 years—born in 1499 during China’s Ming Dynasty. (Image: Canva)