The human lifespan seems like an eternity when compared to a housefly, say, whose entire existence spans only a month tops. But compare it to the oldest animal ever known—a quahog clam believed to be 507 years old in 2013—and we look like spring chickens.1

“Ming” the ancient clam isn’t the only animal that’s seen the turn of several centuries in its lifetime. Indeed, there are tortoises alive in the world today that were around at the same time as Charles Darwin.

From aeonic mollusks to a slew of deep-sea dwellers that will inevitably outlive us all, here are 11 animals with the longest lifespans, including one deemed “immortal.”
Greenland Shark

According to a study utilizing eye lens radiocarbon testing, the minimum life span of a Greenland shark (Somniosus microcephalus) is 272 years, with a maximum reported age of 392 years.2 The authors of the study concluded that the Greenland shark is the longest-living vertebrate known to man.

The IUCN considers this shark near threatened with extinction due mostly to overfishing.3 The Greenland shark lives in the Arctic and North Atlantic waters at depths averaging from 4,000 to more than 7,000 feet. It grows slowly to a length of eight to 14 feet at maturity. It scavenges for its food and eats a variety of fish and birds.
Geoduck Clam

These oversized saltwater clams have been known to live for more than 165 years.4 Geoducks (Panopea generosa) experience rapid growth during their first years of life, acquiring more than an inch per year, on average, in the first four years. Characterized by their long “necks,” or siphons, geoducks can grow to more than three feet in length, while the shell is typically no longer than eight inches.

Geoducks are native to the Pacific Northwest from California to Alaska.
Tuatara

Tuatara are the only surviving members of an order that flourished about 200 million years ago, the Sphenodontia.5 Considered living fossils, these lizaradlike reptiles are among the longest-lived vertebrates on Earth, with some individuals living more than 100 years.6

Found only in New Zealand, tuataras reach sexual maturity after 10 to 20 years and continue growing until they are 35 to 40 years old.
Lamellibrachia Tube Worm

These colorful deep-sea creatures are tube worms (Lamellibrachia luymesi) that have been known to live between 170 and 250 years.7 They live along hydrocarbon cold seep vents on the ocean floor.

The Lamellibrachia is unique among vent creatures because it grows slowly throughout the duration of its life to a length of six-plus feet. It occurs throughout the Atlantic Ocean, especially in shallow portions of the Gulf of Mexico basin.
Red Sea Urchin

The red sea urchin (Strongylocentrotus franciscanus) has a life expectancy of 100 to more than 200 years.8 Found only in the Pacific Ocean, primarily along the West Coast of North America and the northern coast of Japan, the red sea urchin lives in shallow, sometimes rocky waters. It avoids extremely wavy areas and stays primarily from the low-tide line down to 300 feet. It crawls along the ocean floor using its spines as stilts.
Bowhead Whale

Also known as the Arctic whale, the bowhead (Balaena mysticetus) is by far the longest-living mammal on Earth. The average age of captured whales is 60 to 70 years; however, genome sequencing has led researchers to estimate life spans of at least 200 years.9

These creatures are found in the colder waters of the north Atlantic and north Pacific.
Koi Fish

Koi (Cyprinus rubrofuscus) are an ornamental, domesticated variety of the common carp. They have an average lifespan of 40 years, although the oldest known koi lived to be over 200.10

Koi can grow up to three feet in length and are native to the fresh waters of the Caspian Sea. Wild populations can be found in North America, South America, Africa, Europe, and Asia. Koi are common in artificial rock pools and decorative ponds.
Tortoise

With an average lifespan of 177 years, tortoises (Testudinidae) are considered one of the longest-living vertebrates on Earth.11 One of their oldest known members was Harriet, a Galápagos tortoise that died of heart failure in 2006 at the age of 175. Harriet lived at a zoo owned by the late Steve Irwin and was considered the last living representative of Darwin’s epic voyage on the HMS Beagle.

In 2022, a 187-year-old Seychelles tortoise named Jonathan made it into the Guinness World Records as the oldest known living land animal.12
Ocean Quahog

The ocean quahog (Arctica islandica) is a bivalve mollusk that can live for 200 years.13 A lifespan of 100 years is common, we know by measuring age marks formed in the quahog’s valves.

With a habitat that stretches from the east coast of North America to Iceland, the Shetland Islands, and Cadiz, Spain, the ocean quahog has a broad range. The filter feeders bury themselves in the ocean floor and live on microscopic algae.
Antarctic Sponge

Antarctic sponges can thank their environment for their long lifespans: These sponges, of which there are more than 300, live approximately 325 to 6,500 feet underwater in extremely cold temperatures.14 This extreme environment slows down their growth rate and other biological processes, which results in remarkable longevity.

A 2002 study calculated that one Antarctic sponge species, the Anoxycalyx joubini, could potentially live a phenomenal 15,000 years.15 The same study determined that the Cinachyra antarctica, which does not live as deep underwater as the Anoxycalyx joubini, can live up to 1,550 years.
Immortal Jellyfish

The Turritopsis dohrnii species of jellyfish might be the only animal in the world to have truly discovered the fountain of youth. Since it is capable of cycling from a mature adult stage to an immature polyp stage and back again, there may be no natural limit to its lifespan.16

Found primarily in the Mediterranean, the Turritopsis dohrnii species is also an expert survivalist that hitches rides around the world on the bottom of cargo ships.

Why Do Some Animals Live for so Long?
It’s not entirely unheard of for a marine animal to live for a thousand years—or possibly even forever. Meanwhile, a human would be lucky to make it to 100. The secret to longevity, it turns out, is a combination of immobility and slow growth rate.17 Add a deep-sea environment to the mix and you have an organism that is practically immortal.

Terrestrial animals generally have shorter lifespans than marine animals. One reason is because the ocean is a stable environment, and the deeper you go, the less likely you are to die from a chance event.