13 animals that outlive humans by centuries, and what they teach us

Humans have hunted the secret of a long life for as long as they have written anything down, from alchemists boiling minerals into tonics to biotech labs editing genes in a dish. The animals that solved the problem long ago never joined the search. A shark gliding beneath Arctic ice, a clam buried in cold sediment, and a tortoise cropping grass on a remote island all carry on through stretches of time that reduce a full human life to an afternoon. None of them eats better or exercises more. Their advantage lies in biology that slows aging, stops it, or in two cases runs it in reverse.

Researchers who study human aging have proposed a hard ceiling for the body somewhere near 150 years, a limit that arrives as cells gather damage faster than they can repair it. A century and a half looks modest against the spans some animals complete. Creatures that endure for hundreds of years appear to dodge the breakdown that defines human decline. Some mend their DNA with a precision human cells lose by middle age. Others run metabolisms so slow that the chemical wear behind old age accumulates at a crawl. A few rebuild themselves out of stem cells, swapping in new material before the old gives way. Each route poses a practical question for a field that spends most of its effort treating the diseases clustered at the end of a human life instead of the decay underneath them.

Live Science gathered 13 of the longest-living animals alive today and ordered them by estimated maximum lifespan. The list here starts with the two creatures that may never die of old age and moves down to those whose spans close after a few centuries. No research team tracks every individual in a species from its first day to its last, so these figures rest on estimates that biologists piece together from the specimens they recover. Growth layers, radiocarbon dating, chemical analysis of eye tissue, and the capture records that zoos and field scientists keep all stand in for a birth certificate. Salt water and fresh water account for nearly every entry, and the deepest dwellers settle where the temperature holds steady across thousands of years. The 13 entries span jellyfish, sponges, corals, mollusks, worms, fish, reptiles, and a single mammal, and each one answers the question of why bodies fail in its own way.

Illustration: Quartz

Hydra, a group of small soft-bodied invertebrates that resemble jellyfish in miniature, show no sign of growing old, and biologists trace the trait to a body whose bulk consists of stem cells. Those cells copy themselves without pause, cloning fresh material that takes over from worn material before any of it fails. The animal rebuilds itself on a loop, so the decay that creeps through most bodies with age never gathers in one long enough to matter. Age in a hydra marks elapsed time and nothing else.

Daniel Martínez, who teaches biology at Pomona College in Claremont, California, found the absence of senescence in hydra and framed the conclusion without hedging. "They don't seem to age," he said, "so potentially, they are immortal." Martínez stops short of saying hydra cannot die. He argues instead that the clock most organisms run on never starts inside them. His finding sets hydra apart from nearly every other animal researchers have followed from birth to death.

Predators and disease kill hydra in the wild, which keeps them mortal in practice while leaving the underlying biology untouched. Nothing inside the animal sets an expiration point. Remove the external hazards, and a hydra could keep regenerating with no internal limit to stop it. The split between the two kinds of death, the sort that arrives from outside and the sort that builds from within, explains why laboratories studying decline devote attention to a creature this small. Hydra hold the two apart, a separation few other research models offer.

Hydra regrow parts of themselves that other animals lose for good, including their heads. The same stem cells that keep the body from wearing down repair it after injury, fusing upkeep and healing into one continuous process instead of two separate emergencies. Most animals, humans among them, treat recovery as an interruption to ordinary life. A hydra runs on it. A body that handles repair as routine never accumulates the backlog that ends most animals, which leaves hydra with a maximum lifespan no researcher has been able to put a number on.

Credit: Animalia

Turritopsis dohrnii, a jellyfish measuring under 4.5 millimeters (0.2 inch) across, responds to injury and hunger by discarding its adult body and returning to the polyp stage it grew out of. The American Museum of Natural History describes how mature individuals that take physical damage or lose their food supply settle onto the seabed and remake themselves into the earlier form, before rebuilding into swimming adults all over again. The feat earned it the nickname immortal jellyfish.

Every other jellyfish runs its life story in one direction only. A larva anchors to the seafloor and becomes a polyp, the polyp buds off free-swimming medusas, and the bell-and-tentacle adult most people picture lives out its span and dies. Turritopsis dohrnii treats that sequence as reversible, stepping back one stage and then climbing forward through it a second time.

Harm and starvation set the rollback in motion, which makes the escape hatch a reply to crisis instead of to accumulated years. A medusa drifting through calm water with plenty to eat keeps deteriorating on the ordinary schedule. Adversity is what drives this one into retreat, converting the sort of emergency that finishes most marine animals into the trigger that starts it over.

Repetition turns the maneuver into a true loophole. The Natural History Museum in London notes that an individual can run the cycle backward more than once, and under favorable conditions it may never die of old age. The species makes its home in the Mediterranean Sea, and no researcher has yet established a ceiling on how many times an animal can repeat the performance.

Predators keep the biology from producing anything deathless. Fish and other hunters eat Turritopsis dohrnii, and assorted hazards claim individuals long before the capacity to restart ever matters, which is why the Mediterranean holds no population of jellyfish that have lived forever. Senescence is the only enemy this animal has defeated, and in a sea crowded with hungry fish, victory over aging buys less than the nickname suggests.

Illustration: Quartz

A glass sponge of the species Monorhaphis chuni reached an estimated age of about 11,000 years, according to a 2012 study in the journal Chemical Geology. The number dwarfs every age attached to an animal with a conventional life span, more than doubling the oldest radiocarbon-dated black coral. The longest-lived vertebrates on this list fall short of the sponge by more than 10,000 years. Only the hydra and the immortal jellyfish, each able to restart its own biology, rank above it.

Many organisms share the body of a single glass sponge, which grows as a colony in the fashion of a coral. Among sponges, the glass varieties reach the greatest ages, and the wider group counts its longest-surviving members in thousands of years. NOAA traces the common name to the skeleton, whose structure takes on the look of glass. These sponges settle in the ocean's lower reaches, far from the lit shallows where most familiar marine life gathers.

Conditions that hold their temperature and chemistry from one century to the next explain why the oldest animals on Earth cluster in deep water. A coastal reef absorbs storm surges, tidal swings, and seasonal crashes in food supply across centuries, while a sponge rooted to the floor meets none of them. The pattern repeats down this list, where the animals living farthest from the surface post the highest ages. Calm of that order strips away most of the events that cut an animal's life short of old age.

Other sponge species may outlast Monorhaphis chuni, a prospect that turns the 11,000-year estimate into a floor instead of a ceiling. The 2012 figure holds as a record only among the specimens scientists have retrieved and measured, and researchers have sampled a thin slice of the seabed these sponges occupy. Few specimens from that far down reach a laboratory, which leaves most of the group's record-holders uncounted. The oldest animal alive may be sitting in the dark on a patch of ocean bottom no vessel has reached.

Illustration: Quartz

Black coral growing off the coast of Hawaii carries a radiocarbon age of 4,265 years, which puts deep-water members of this group among the oldest corals scientists have dated. No single creature inside the coral holds a continuous body of its own. What a diver reads as a branching mineral formation consists of exoskeletons that soft invertebrates called polyps produce, and the age belongs to all of them at once.

Polyps build their colonies by copying themselves. Each one produces a clone that carries the same genes, and the accumulated exoskeletons widen the standing framework season after season, so what appears to be one animal functions as a crowd of duplicates arriving in sequence. Death arrives one polyp at a time, and a substitute fills every gap, which keeps the colony's identity fixed across centuries. No individual polyp lives for 4,265 years. The colony does, and each new copy that takes the place of the last carries it forward.

Age under such an arrangement amounts to a shared achievement that generations of tiny animals compile, instead of one body's capacity to absorb damage. A single polyp needs no gift for DNA repair and no slow-burning metabolism, the traits that extend the years of a clam or a whale on this list. Its own turn lasts a sliver of the colony's history, and the lineage keeps adding to what already stands. The black coral off Hawaii began building more than four millennia ago, and successive polyps have extended the same mass in every century since.

Deep water off Hawaii suits a growth strategy of pure addition, since temperature and chemistry hold steady far below the surface. Every generation's contribution stays in the structure, so the coral carries a record of its own construction. A black coral's age measures how long a chain of copies has held together, which makes the oldest animals on Earth easier to count in years than to define as individuals.

Illustration: Quartz

Researchers at National Museum Wales in the U.K. examined Ming, a quahog clam recovered from the seabed near Iceland in 2006, and calculated its age at 507 years. The clam owes its nickname to the Chinese dynasty in power at its birth in 1499, the Ming, whose rule over China ran from 1368 to 1644. A single bivalve on the ocean floor outlasted the whole of that dynasty and the four centuries that followed it.

Arctica islandica inhabits the North Atlantic, and the species outlives the freshwater pearl mussel, the only other bivalve on this list, by more than two centuries. Nothing about the clam suggests exertion. It settles into the sediment and adds shell at a pace an observer would read as stillness.

Anna Holmes, curator of invertebrate biodiversity for bivalves at National Museum Wales, credits temperature for the record. In a 2020 post for the museum, she wrote that Icelandic seas hold the quahog's metabolism down, which drags out its growth, and she expects members of the species to live past 507 years. No one, she noted, has yet pulled up an older specimen.

A body kept at low temperature spends less energy each year than a warm one, and the quahog converts that economy into time. Slower growth stretches the span between one stage of life and the next, which pushes the end of a life further out. Temperature works as the clock here, and chillier seas slow its hands. The clams buried off Iceland sit in the frigid margin of the species' range, which may explain why the record holder turned up there and not in milder stretches of the North Atlantic.

Ming's 507 years describe the oldest quahog anyone has examined, which is not the same as the oldest quahog alive. Every unexamined clam in the mud off Iceland is a candidate for a higher number. The 507-year mark stands as a floor beneath a figure nobody has measured.

Illustration: Quartz

A 2017 paper in The Science of Nature documented individual Escarpia laminata, a tubeworm anchored to the Gulf of Mexico seafloor, surviving past 300 years, while the species as a whole commonly reaches 200 years of age. The worm never relocates. It builds a tube, settles into one patch of seabed far below the reach of sunlight, and remains there while three centuries of ocean history pass overhead.

Tubeworms get by without eating. The Woods Hole Oceanographic Institution's Dive and Discover $DFS project reports that microbes living inside each tube convert seabed chemicals into sugars, and the worm relies entirely on that supply for nourishment. The arrangement erases hunting, foraging, and competition for prey from the animal's day. A deep-sea predator spends energy chasing meals and risks injury in the process. A tubeworm accepts delivery from the bacteria it houses and pays nothing for the service.

Address decides which tubeworms reach extreme age. The University of Hawaii's Exploring Our Fluid Earth resource notes that many tubeworm species cluster near hydrothermal vents, yet the longest-lived populations inhabit cold seeps instead, cooler locations where chemicals seep out through cracks in the seafloor. Conditions at a seep hold steady across stretches of time long enough for a shallow reef to form and collapse several times over. Temperature holds within a narrow band. The chemical supply keeps arriving. A worm that settles at one of these sites inherits surroundings that shift less across 300 years than a coastline shifts in a decade.

Researchers tie the extended survival the 2017 work recorded to a sluggish metabolism and the scarcity of predators at such depths. A body burning energy at minimal rates accumulates little of the internal damage that ends shorter lives, and almost nothing at the bottom of the Gulf hunts an animal sealed inside its tube. Few creatures in any habitat face a lower daily chance of dying. Extreme age in the deep ocean falls to whatever finds a place where events stop happening.

Illustration: Quartz

A 2016 study in the journal Science put the maximum age of the Greenland shark at no less than 272 years, a figure the research team drew from the animals' eye tissue. The largest specimen in that sample came in at 392 years old, and the same work left room for an upper boundary near 512 years. Even the cautious end of the range lifts the species above every other animal with a backbone, a standing no fish, reptile, bird, or mammal has challenged since.

Somniosus microcephalus hunts the deep water of the Arctic and North Atlantic, reaching 24 feet (7.3 meters) in length and preying on fish along with seals and other marine mammals, according to the St. Lawrence Shark Observatory in Canada. A predator of that size lives where the temperature holds steady from one century to the next, the kind of cold, unvarying habitat that nearly every creature of extreme age occupies.

Julius Nielsen, a researcher at the Greenland Institute of Natural Resources, has stressed to Live Science that the low end of the reckoning, 272 years, leaves the species without a rival among vertebrates. The arithmetic behind the larger numbers stretches further still. A shark the team dated to 392 years in 2016 would have hatched around 1624, and one at the 512-year mark would have entered the water near 1504, centuries before anyone thought to ask how long a shark could live.

The 240-year gap between the floor and the ceiling of those figures spans more than two centuries on its own, which means the uncertainty around a single Greenland shark exceeds the full life of nearly every other vertebrate scientists have measured. The researchers behind the 2016 work acknowledged a degree of doubt in their own dating, and the species' true upper limit remains unsettled. Few other long-lived animals come with a window that wide. Scientists know the shark outlasts every other animal they have aged, without yet knowing by how much.

Illustration: Quartz

The oldest freshwater pearl mussel on record reached 280 years, an age the World Wildlife Fund for Nature credits to a metabolism that idles at close to nothing. Margaritifera margaritifera passes that entire span wedged into the gravel of rivers and streams across Europe and North America, straining particles of food from the current washing over its shell. A bivalve that never chases prey, never flees at speed, and never heats its own body spends little of the energy that drives chemical damage in more active creatures.

Low-energy biology buys the mussel centuries and pins the animal to one patch of riverbed for the whole of that span. A mussel cannot move on when a stream silts over, warms, or loses the clean flow it needs for food. A sedentary existence stretching past two centuries leaves no escape route from a changing current. Survival depends on a river that behaves much the same in a mussel's 200th year as it did in its first.

The International Union for Conservation of Nature classifies the freshwater pearl mussel as endangered. People have damaged and reworked the river habitats the species occupies, and its numbers keep falling across both continents where it lives. An animal able to span three human lifetimes has no defense against a waterway that people remake inside a single one.

A mussel reaching 280 years would have settled into its gravel bed long before industry transformed the rivers of Europe, filtering the same stretch of water through every upheaval that followed. A single long life says nothing about whether the species as a whole will hold on. The record marks what one shell can withstand when a river stays clean and steady, a condition that has grown scarce across much of the species' range.

Longevity records and conservation lists measure different things. The freshwater pearl mussel sits on both, evidence that a body built to endure nearly three centuries still needs a river that holds together around it.

Illustration: Quartz

Rougheye rockfish can live past 205 years, a maximum documented by Washington's Department of Fish and Wildlife that ranks them among the longest-lived fish anywhere in the ocean. Canada's Committee on the Status of Endangered Wildlife lists this pink or brownish species as a Pacific inhabitant ranging from California to Japan, growing up to 38 inches, and preying on shrimp and smaller fish. Anglers sometimes call it the blackthroat rockfish or blacktip rockfish instead.

Genetic markers tied to unusual age turned up across the rockfish family in 2021, when a team writing in the journal Science compared the genomes of 88 species with the rougheye among them. Several markers sit in pathways the fish use to repair damaged DNA, upkeep that may hold off the cancers capable of ending a rockfish early. Machinery that keeps copying errors from piling up matters more in a body built to last two centuries than in one that spawns and dies within a decade. The pattern points to identifiable stretches of genome behind the trait instead of luck in one isolated lineage.

Extra decades pay the rougheye back in body size and offspring. Continued feeding over a century or more lets the fish outgrow shorter-lived relatives, and the same stretch of time lets it produce more young across a lifetime. Size and age reinforce each other in a creature that can afford to wait, since every additional year of growth widens the gap between a rougheye and the quicker-burning species sharing its depths. Reproduction spread over such a run means one adult contributes to the population through warm years and cold ones, strong spawning seasons and failed ones.

Eighty-eight close relatives inside a single family hand aging researchers a rare test case, species separated by little more than how many years their bodies keep working. Comparisons that tight make it easier to tell which genes matter for a long life and which came along for the ride.

Illustration: Quartz

Bowhead whales live past 100 years and may stretch beyond 200, an estimate NOAA rests on a peculiar line of evidence. Hunters in the Arctic have cut stone harpoon points out of harvested bowheads, weapons from an era of whaling that ended generations before those animals died. The species' true ceiling remains unknown, yet no other mammal has left proof of a comparable run, which seats the bowhead at the head of its class.

A mutation in the ERCC1 gene may account for part of the whale's defense against the chief hazard of a long life. ERCC1 oversees the repair of damaged DNA, and the bowhead's variant of the gene could shield the animal from cancer, a plausible killer for any body collecting cellular damage across two centuries in Arctic and sub-Arctic water.

A second gene points toward the aging process itself. The bowhead genome holds a duplicated stretch of PCNA, a gene that governs how cells grow and rebuild themselves, and the extra copy could slow the deterioration that overtakes other large mammals decades earlier. Two genetic quirks, one guarding against disease and one tuning the pace of cellular upkeep, sit in the same animal.

João Pedro de Magalhães, who researches the biology of growing old at the University of Birmingham, warns against reading any single gene as a universal key. Long-lived species, he has said, rely on different "tricks" to stretch their spans, and few genes recur across them. He has also noted that certain pathways surface again and again, which hints at "common patterns" beneath the variety. His caution cuts both ways, since repeating pathways across unrelated species hand researchers a shorter list of places to look.

Bowheads sharpen that search more than most candidates, because a whale and a person share the basic architecture of a mammal. A species that holds cancer at bay for 200 years suggests that extreme age rests on a body able to stop its own cells from turning against it.

Illustration: Quartz

Red sea urchins off the coast of British Columbia, Canada, reach roughly 200 years of age, a figure researchers reported in the journal Fishery Bulletin in 2003. Scientists once credited the spiny invertebrates with about 10 years at most, assuming the animals grew fast and turned over their generations at speed. The revision multiplied the accepted maximum by 20. Closer examination of a species already well known to biologists produced the correction.

Strongylocentrotus franciscanus browses marine vegetation in the shallows of the Pacific coast between California and Alaska, according to Oregon State University. A small, round body bristling with spines offers no clue to the animal's age. Detailed examination showed growth that continues through adulthood, creeping along at a rate that lets an individual keep adding size for a hundred years and more. The unhurried pace also means a large red sea urchin is an old one. Urchins that evade predators, disease, and the fisheries working the same water survive far beyond a human lifetime.

Estimates for urchins in the waters off Washington state and Alaska run past 100 years, while the oldest individuals on record come from British Columbia, where the 2003 work put the upper figure at about 200 years. A full century separates two populations of the same animal. Local conditions along a given stretch of Pacific coastline, including which hunters and which fleets an urchin has to outlast, appear to decide how much of its biological potential the animal ever spends. No single maximum age describes the species across its whole range.

Shallow water sets the red sea urchin apart from most entries here, since the deep, cold, unvarying habitats that explain the other extreme ages play no part in its story. Two hundred years of survival in sunlit coastal rock demand only that an animal eat little, grow by increments, and stay out of reach of whatever hunts it. Scientists spent years filing the species away as a short-lived grazer before anyone checked, leaving an open question about how many other familiar coastal animals carry ages nobody has bothered to measure.

Illustration: Quartz

Jonathan, a Seychelles giant tortoise on the island of St. Helena in the South Atlantic, has reached an estimated 190 years, which makes him the oldest land animal alive today. Guinness World Records made the distinction official on Jan. 12, 2022, naming him the oldest tortoise on record. People carried him to St. Helena from the Seychelles in 1882, and a photograph taken between 1882 and 1886 shows a mature adult, placing his age beyond 50 before anyone on the island had reason to count.

Joe Hollins, the veterinarian who tends to Jonathan, values the tortoise for reasons that have nothing to do with arithmetic. He calls his patient "a local icon," a figure who stands for persistence while everything around him changes. No record of Jonathan's hatching survives, so the number attached to him stays an approximation anchored to the maturity visible in that 19th-century photograph.

Predators drive the evolutionary logic behind such ages. Giant tortoises lose a large share of their eggs to nest raiders, so a female who breeds a single time contributes almost nothing to the next generation. Losses on that scale would end a shorter-lived reptile's line within a few seasons. Adults that keep laying clutches across decades leave far more descendants, and selection has favored animals that stay fertile long after most other vertebrates finish. Staying alive, under that pressure, functions as a reproductive strategy.

Tortoises also strip out damaged cells, the kind that decay with age in other animals, and researchers suspect that cleanup helps explain how long members of the group survive. Worn cells pile up in most bodies and drag down the healthy tissue around them. Biologists who study human decline pay attention to a reptile that keeps clearing the debris nearly two centuries in.

Two forces hold Jonathan's 190 years in place, a nest robbed often enough to reward decades of breeding and a body that discards its own failing parts. Tortoise age, on that evidence, begins in the vulnerability of the eggs and not in the armor of the adult.

Illustration: Quartz

Cassius, the largest crocodile held in captivity anywhere, carries an estimated age of up to 120 years and has not finished growing. His 1984 capture on a cattle property to Darwin's southwest brought in an animal measuring 16 feet, 10 inches from snout to tail, a size that led experts to guess he had lived somewhere from 30 to 80 years. Keepers at Marineland Crocodile Park on Green Island have looked after him every year since, and by 2023 their figure for his age had climbed to 120. The 50-year spread in that initial guess shows how little the bulk of a grown crocodile reveals about its years.

Toody Scott, a crocodile keeper who cares for Cassius, has framed the animal's continued expansion as a source of "serious knowledge on longevity" for scientists. The species offers no firm ceiling to work from, since reliable records of maximum age remain scarce. One animal that keeps feeding, swelling, and surviving decade after decade becomes a running measurement of what a saltwater crocodile can manage, taken in real time instead of guessed at after death.

Mr. Freshie, another saltwater crocodile with a documented history, lived an estimated 120 to 140 years, a span the Courier Mail reported. Steve Irwin and his father captured him in 1970 in North Queensland, where experts put his age near 100 at the time. He then spent 40 years at Australia Zoo before dying in 2010, which means his keepers tended a reptile hatched sometime in the 1870s.

Crocodiles of this species that reach adulthood tend to clear 70 years, so Cassius and Mr. Freshie both exceeded the ordinary benchmark by half a century or more. Their records share one weakness. Neither animal has a known hatch date, and each figure grew out of a judgment people formed on meeting a full-grown reptile for the first time. Every published number marks a floor, leaving the true upper reach of the species somewhere past the oldest individual anyone has measured.