The Animals With the Longest Lifespan on Earth and the Biology Behind Their Longevity

In 2006, researchers at Bangor University pulled an ocean quahog clam, Arctica islandica, from the seabed off Iceland and counted its growth rings the way a forester reads a tree. The rings said 507 years. The clam, nicknamed Ming, had been alive when the Mughal Empire was still being founded. Scientists confirmed the age through independent radiocarbon dating of the shell carbonate, making it the oldest non-colonial animal ever recorded with verified evidence.
The ocean quahog's longevity is partly metabolic. These clams have an exceptionally low rate of oxygen consumption relative to their body mass, which limits the production of reactive oxygen species, the cellular byproducts that accelerate aging in most animals. Less oxidative damage means slower biological deterioration. Ming was not a freak specimen; the species routinely lives past 200 years, and researchers use their shells as climate archives, reading centuries of ocean temperature shifts in the same rings that mark age.The Greenland shark holds the record among vertebrates. A 2016 study published in Science by Julius Nielsen and colleagues at the University of Copenhagen used radiocarbon dating of proteins in the eye lens nucleus, proteins laid down at birth and never replaced, to estimate the ages of 28 Greenland sharks. The oldest was a female measuring 5.02 metres, estimated at 392 years, with an uncertainty range placing her birth anywhere between 272 and 512 years ago. The species matures sexually at around 150 years.
What slows them down is temperature and pace. Greenland sharks live in near-freezing Arctic and sub-Arctic waters, and their metabolic rate is among the lowest of any living species. Cold biology is slow biology. Their growth rate is roughly one centimetre per year. Every biological process that wears an animal out, cell division, protein turnover, immune activation, runs at a fraction of the speed seen in warm-water animals of comparable size. Lifespan, in this case, is almost a side effect of extreme physiological restraint.Turritopsis dohrnii, a jellyfish roughly 4.5 millimetres across, does something no other known animal can do at scale: when stressed, injured, or old, it reverts to its juvenile polyp stage and starts its life cycle again. The process is called transdifferentiation, mature, specialised cells convert back into undifferentiated stem-like cells, which then rebuild the organism from scratch. The animal does not repair itself. It restarts.
Shin Kubota at Kyoto University has maintained laboratory colonies of T. dohrnii for years, documenting repeated cycles of reversion and regrowth in individual specimens. Whether this makes the species technically immortal in the wild is debated, they still die from predation, disease, and physical damage. But the cellular mechanism itself has no known biological limit. Aging, for this animal, is a reversible state rather than a terminal one.Across species with exceptional longevity, several biological features recur. Telomere maintenance is one. Telomeres are the protective caps at the ends of chromosomes; they shorten with each cell division, and when they become critically short, the cell stops dividing and eventually dies. Bowhead whales, which live past 200 years, show unusually stable telomere lengths and carry gene variants in ERCC1 and PCNA, genes associated with DNA repair, that appear more efficient than those in shorter-lived mammals. A 2015 study in Cell Reports sequencing the bowhead whale genome identified these variants as likely contributors to both cancer resistance and extended lifespan.

Naked mole rats offer a different angle. These small rodents live over 30 years, roughly ten times longer than a similarly sized mouse, and show what researchers call negligible senescence: their mortality rate does not increase meaningfully with age. Vera Gorbunova and Andrei Seluanov at the University of Rochester have documented that naked mole rat cells produce an unusually pure form of ribosomal RNA, which reduces the rate of protein synthesis errors. Proteins that fold incorrectly accumulate with age in most animals and drive cellular dysfunction. Naked mole rats make fewer mistakes at the source.
Telomeres, DNA repair fidelity, metabolic rate, and the speed of cell division are not separate strategies. They are different levers on the same underlying problem: how quickly does accumulated biological damage outpace the body's ability to correct it?The biological mechanisms behind animal longevity are directly relevant to aging research in humans. The FOXO3 gene, variants of which appear in long-lived bowhead whales and also in human centenarian populations in Okinawa and Sardinia, regulates cellular stress responses and DNA repair. Craig Wilcox and colleagues published findings in 2008 in the journal Rejuvenation Research linking specific FOXO3 variants to exceptional human survival past 100 years. The gene did not appear in isolation, it interacted with diet, activity, and environment, but the biological substrate was the same one found in animals that outlive us by centuries.

The ocean quahog's oxidative damage restraint, the Greenland shark's metabolic minimalism, the naked mole rat's protein synthesis accuracy, and T. dohrnii's transdifferentiation are not four separate miracles. They are four different answers to the same question biology keeps asking: what is the minimum rate at which a living system must spend itself to stay alive? The animals that live longest are the ones that found the most efficient answer.
Every longevity mechanism researchers have identified in these species has a human analogue, a gene, a pathway, a cellular process that runs in us too, just faster and with less precision. The oldest animals on Earth are not outliers. They are the clearest data points we have on what the biological ceiling for survival actually looks like.