Imagine gliding through deep, icy waters, untouched by the passage of centuries. No wars, no automobiles, no smartphones—just silent currents and endless dark. That is the life of a Greenland shark, and one such shark may have been alive since the 1600s.
A Shark That Outlives Nations
Researchers believe Greenland sharks (scientific name Somniosus microcephalus) hold the record for the longest-living vertebrate on Earth. Estimates point to lifespans of around 400 years or more. Scientists have used radiocarbon dating on proteins in the lens of the shark’s eye to estimate age. In one study, the oldest specimen was estimated at 392 years (with a margin of error) — meaning it could have been born as early as the early 1500s or as late as the 1700s.
If that’s true, this shark would have witnessed centuries of change above the surface: the rise and fall of empires, the dawn of industrialization, the invention of electricity, and the digital age—and yet, deep below the waves, she continues her quiet existence.
Slow Motion in the Deep
Greenland sharks live in extremely cold, dark waters of the North Atlantic and Arctic oceans. Their metabolism is slow, their movements deliberate. They swim at just about 0.3 meters per second (roughly 1 foot per second) on average. This slowness helps conserve energy and likely contributes to their long lives.
Counting “rings” in bones, as scientists often do for fish, doesn’t work here—their vertebrae don’t preserve clear markers. Instead, the trick lies in eye lenses. The inner core of the lens forms before birth and doesn’t change. Over time, new layers build around it. Researchers date the inner core’s carbon signature, compared to known atmospheric levels, to estimate how many years have passed.
Secrets in the Genome
Understanding how a creature lives centuries is a biologist’s dream. Recent research has decoded parts of the Greenland shark’s genome, revealing clues about how it avoids the ravages of aging. Scientists have found that the shark’s DNA is packed with so-called “jumping genes” (transposable elements), which typically cause damage in many species—but in the Greenland shark, other genes may hijack or balance this activity to replicate or repair important DNA regions.
Another intriguing find: the shark’s version of a vital protein called p53, known for protecting against cancer in many animals, is slightly altered. Researchers think this variation may help the shark resist mutations and cancer over centuries.
Tough Beginnings, Slow Maturity
Longevity comes with tradeoffs. Greenland sharks take a long time to reach sexual maturity—around 150 years. When mature, they give live birth after a likely gestation period of many years. Because of this slow life cycle, their populations are especially vulnerable to threats. Overfishing, bycatch, and environmental changes can hit them hard, since a lost shark cannot be replaced quickly.
Why Her Life Matters
This ancient shark reminds us of time in a new way. When we speak of centuries, we often mean maps, wars, kings, and inventions. But here is a life that spans all that, floating far beneath.
For your readers, you can imagine:
While Shakespeare was writing, she was already a juvenile shark.
While Columbus’s world expanded, she was dancing in the deep.
As steam engines puffed and factories rose, she drifted in silence.
As rockets launched and we linked the globe by wires, she remained in her underwater realm.