Oldest Creatures That Reveal The Secrets Of Immortality

Some creatures in the world offer explanations for the secrets of immortality. Let's find out about the oldest creatures in the world!

October 5, 2023・

10 min read

For most of us, the future inevitably means getting old and swapping our health for wrinkles. But some creatures on Earth can resist aging to an unbelievable extent, and some even escape it entirely. We can learn a lot from Earth’s oldest life forms, as they could hold the secrets to immortality. From 500-year-old sharks to resurrected, million-year-old anomalies, let’s take a look at the creatures of the Earth that reveal the secrets of immortality.

Tuataras

Often described as a living fossil, the tuatara can only be found on the offshore islands of New Zealand. Its nickname isn’t just a mean joke; tuataras well and truly earn their description as fossils, as they’re thought to be capable of living up to 200 years.

Having roamed the Earth since as far back as 225 million years ago, the Tuataras of today have changed little since the last T-Rex kicked the bucket. Their survival and longevity are in part due to their hardy nature, being able to survive in a wider range of temperatures than most other lizard species.

On top of this, they have exceptionally slow metabolisms, and they seem to prefer a leisurely pace of life. It can take them up to 40 years to reach full size, usually around 2 1/2 ft, and they don’t even reach sexual maturity until they’re around 20.

But despite being late bloomers, evidence suggests they’re constantly "virile" right until the end of their lives. A Tuatara in captivity called Henry highlighted the amorous capabilities of his species when he became a father at the ripe old age of 111. This was after almost forty years of showing no interest in females. So, remember fellas, it’s never too late. Just channel your inner Henry the Tuatara.

Aldabra Giant Tortoise

Sitting at the top of the pile of the oldest terrestrial animals on Earth is the Aldabra Giant Tortoise, found on the islands of the Aldabra Atoll in the Indian Ocean. The age and longevity of these wrinkly reptiles is embodied by Jonathan the Tortoise who is currently about 190 years old.

He hatched in 1832, before antiseptics, automobiles, or even the telegraph had been invented. But despite being the oldest living Aldabra Tortoise, Jonathan’s a wee lad compared to previously recorded members of his species, who’ve been known to live for over 200 years. Adwaita, another Aldabra Giant, was estimated to have been 250 years old when he died in 2006.

While their ages are often hard to verify, as the tortoises have a mildly inconvenient tendency to outlive their observers, there’s little doubt that this species is Earth’s oldest land-based vertebrate. Research suggests that their longevity is facilitated by a combination of very slow metabolisms and impressive genetics.

Their unique bodies are able to repair DNA and fight cancer and inflammation in remarkable ways that science has yet to fully understand. But if Jonathan & Adwaita are anything to go by, the secrets of immortality may lay somewhere between tropical weather and beautiful beaches.

Bowhead Whale

Named after their bow-shaped heads, the Bowhead whale grows up to 60 feet and can weigh up to 100 tons. A healthy daily diet of 2 tons of food means the Bowhead whale eats like a bodybuilder stuck in the bulking phase. Bulking is necessary, though, as these giants are found in freezing Arctic waters and suitably possess the thickest coating of blubber of any sea mammal, up to 20 inches thick.

But their diet is far from the most fascinating fact about them, as these guys can live for over 200 years, making them the longest-living mammals on Earth. Their extreme longevity is all thanks to supremely optimized genetics, which allow for cells to be repaired and replaced with ultimate efficiency.

But cell replacement is required much less than in humans, as bowheads’ cold environments mean their cells receive far less wear-and-tear than our own. So maybe your roommate has a point when they insist on turning the thermostat down.

Red Sea Urchins

This creepy, spiky organism is found in shallow waters of the Pacific Ocean. You’ve probably seen (or stepped on) their black cousins, which also deliver a nasty sting, on beaches around the world. The red variety grows continually, usually up to around 7 inches in diameter.

According to scientists, the Red Sea Urchin can live over 200 years of age, with no decline in its ability to heal or reproduce. Indeed, the Red Sea Urchin is able to reproduce way past the age of the average pensioner. Evidence suggests a 100-year-old red sea Urchin is just as capable of reproducing as a 10-year-old sea urchin. In fact, the older they get, the more prolific producers of sperm and eggs they become.

The exact mechanisms of this ability to avoid declining health with age are not fully understood, but their implications are profound.

The Red Sea Urchin’s seeming lack of aging threatens to destabilize the accepted theoriesof why aging occurs in the first place. For now, maybe we should just cover ourselves in spikes instead of anti-aging cream; it seems to work for the little red guys, after all.

Greenland Shark

In the cold waters of the North Atlantic and Arctic Oceans lives the oldest vertebrate on Earth. At up to 21 feet long and weighing over a ton, the Greenland Shark is an apex predator in its habitat, preying on everything from fish to seals and even polar bears.

A lack of predators, and more importantly, an incredibly well-adapted body allows these creatures to live from 200 to 500 years and upwards. With so much time, it seems there’s no need to rush. Its average speed is around 1 foot per second, and its heart only beats once every 12 seconds or so.

The cold water they live in is associated with a very slow metabolism and maturation, meaning their cells denature at a much slower rate than ours. This is thought to be central to their longevity. Intriguingly, most Greenland sharks are blind, thanks to parasites called copepods, which tend to attach themselves to the sharks’ corneas.

Quahog Clams

Icelandic Ocean Quahog clams are known for their slow aging, but scientists were struck with disbelief when they opened up one particular specimen in 2013. In the same way you’d count the rings of a tree, scientists counted the clam’s densely-packed growth rings, calculating its age to be an astounding 507 years.

Unfortunately, when the researchers opened the clam to do so, they accidentally killed what turned out to be the oldest specimen of its kind known to man.

Like many of Earth’s oldest living species, scientists believe the secret of the Ocean Quahog’s longevity is an incredibly slow metabolism. The creature lives an uneventful life in water near the edge of the ocean, buried in the sand, feeding on phytoplankton that float past with its weird, undulating tongue.

Noticing a pattern here? The secret to long life seems to be stress-free lifestyles near bodies of water, where the food basically comes to you. Did someone say permanent, all-inclusive vacation to the Bahamas?

Immortal Jellyfish

For one amazing creature, aging is less a straight line and more a circle. The jellyfish scientifically known as Turritopsis Dohrnii has the incredible ability to reverse its aging process; making it biologically immortal.

When an adult is injured or faced with starvation, this fingernail-sized creature re-assigns the functions of its cells, inducing a transformation that would make the Incredible Hulk blush. It slowly reverts back into its juvenile polyp state, losing its tentacles, and shrinking down to fun-size, like when Tom Cruise takes his platform shoes off.

From here, it creates countless genetically identical clones through asexual reproduction, and the circle of jelly life continues. Of course, the immortal jellyfish can still be eaten by predators, so there’s a way to go before it reaches full immortality. That is good for us because a world overrun with invincible, self-replicating jellyfish doesn’t sound too fun.

34,000-Year-Old Organisms Found Buried Alive

When scientists uncovered ancient salt crystals in Death Valley, California in 2011, they were blown away by the bacteria they found trapped inside. Usually, finding bacteria in the ground would be unremarkable, but these bacteria cells had beentrapped there for 34,000 years!

The bacteria lived in tiny, fluid-filled chambers inside the salt crystals, spending most of the past 34 millennia in a state of hibernation. To survive, they’d shrunk in size and stopped moving, excreting, and most other functions. Scientists are still baffled as to how the bacteria managed to prevent its DNA from degrading over such a long period.

That being said, the presence of algae cells within the salty, ancient micro-chamber suggests the bacteria may have intermittently reanimated to feed, in its very own microscopic ecosystem. But waking an ancient creature from its slumber isn’t a quick task. The microbes took two months to wake up from hibernation, which sounds pretty relatable to me. As the Genie from Aladdin said, 34,000 years will give you such a crick in the neck!

Ancient Worms

If preserving yourself in salt crystals isn’t your cup of tea, why not try getting frozen in permafrost for a while? It certainly worked for members of two known species of microscopic worm, Panagrolaimus Detritophagus and Plectus Parvus. These specimens, which are scarcely longer than a grain of sand, were trapped in the frozen Siberian ground for thousands of years before their discovery in 2018.

Upon thawing, they were soon chowing down on a well-earned meal; their first in 42,000 years. How multicellular organisms like these can survive cryobiosis (or freezing of their cells) for such a long time remains shrouded in mystery. While the implications for human preservation are potentially enormous as we learn more, for now, it’s just plain cryo-confusing.

Old Snapping Turtle

Before we get to the oldest living thing on our little blue planet, time for a pit-stop with some honorable mentions. First up is this individual snapping turtle from Texas that, by all appearances, seems among the world’s most ancient.

While a coating of algae is common on the shells of many turtle species, this excessive amount suggests either great age or disease. However, the turtle’s bright blue, cataract-ridden eyes suggest extreme age rather than disease. After all, snapping turtles are known to live up to 200 years old, so we can’t be too hard on the old fella!

Hydra

Hydra is a tiny organism found in freshwater all over the world. Thanks to most of its body being composed of stem cells, the hydra is able to regenerate its body in the case of injuries.

An offshoot of this amazing ability is that it doesn’t appear to age, making it similar to the immortal jellyfish in its potential longevity. In captivity, free from predators, scientists believe the hydra is able to live indefinitely, which is at least as impressive as its mythical counterpart.

Yeast Fungus

The story of this still-living being stretches way back, to the times when Australia had only just split from Antarctica, and modern mammals were only beginning to appear. Somewhere around this time, known as the Eocene epoch, a microscopic fungus related to modern baker’s yeast was struck by misfortune.

The resin from a nearby tree encapsulated the fungus, hardening into amber around it. An astonishing 45 million years passed before microbiologist Raul Cano cracked the amber open for an experiment in the 1990s.

After rigorously sterilizing it to prevent contamination by modern microbes, he froze the amber in liquid nitrogen, shattered it into fragments, and distributed it into Petri dishes. Cano was amazed to see that the fungus came back to life and started feeding and reproducing.

At that moment, the 45-million-year-old yeast became the oldest known living creature on earth, thanks to one special ability. Some creatures like the ancient yeast are able to enter a hibernation state, without eating or drinking, seemingly indefinitely, and can then resume living once conditions become more suitable.

But most amazingly of all, the yeast was swiped up by an intrigued beer brewer and crafted into a reportedly delicious ale. Indeed, you can now purchase beer from Fossil Fuels Brewing Company that’s made from 45-million-year-old yeast. Forget Jurassic Park, this is what science is all about.

I hope you were amazed by these oldest creatures that reveal the secrets of immortality. Thanks for reading!