Despite their slow swimming speed, Greenland sharks are predators and scavengers that feed on a variety of marine animals.
Their documented prey includes fish and other marine organisms. Researchers have also found remains of larger animals in their stomach contents, although the presence of such remains does not always establish whether the shark actively hunted the animal or consumed it after death.
This flexibility may help the species survive in an environment where meals can be unpredictable.
Deep and cold waters do not always provide the abundance of food available in more productive surface environments. An animal living there may benefit from being able to take advantage of different food sources rather than relying on one particular prey species.
Scavenging can be especially useful in this context. When an animal dies and its remains become available, scavengers help transfer energy through the ecosystem by consuming material that might otherwise decompose without being eaten by larger predators.
Greenland sharks are therefore part of a complex marine food web, interacting with fish, marine mammals, and other organisms.
Their ecological role is not completely understood, partly because they are difficult to observe directly. Scientists continue to investigate how their feeding habits change with age, location, season, and food availability.
It is also important to separate popular claims from established observations. The discovery of an exceptionally old Greenland shark does not mean the animal has survived for centuries by eating a particular food or following a specific routine. There is no single confirmed explanation for its longevity.
Instead, its extraordinary lifespan likely reflects a combination of biological characteristics and environmental conditions that scientists are still working to understand.
Could There Be Sharks Alive Today That Were Born Centuries Ago?
Yes, it is scientifically plausible.
The 2016 research established that at least some Greenland sharks may live for several centuries. NOAA notes that their lifespan may exceed 500 years, although precise ages remain uncertain.
Because Greenland sharks are still present in Arctic and North Atlantic waters, it is possible that some living individuals were born hundreds of years ago.
However, researchers have not identified a living shark and definitively confirmed that it was born in the 1600s. The existence of such individuals is a reasonable possibility based on the species' estimated longevity, not a verified count of ancient sharks currently alive.
This uncertainty makes the discovery even more intriguing.
A shark swimming beneath the Arctic ice today could have been born before the industrial revolution, before the invention of the telephone, or before the first automobiles appeared on public roads.
Another might have been alive before the first powered airplane flight.
We cannot know the history of any particular individual without more precise evidence, and the current dating method cannot provide an exact birthday for every living shark.
Nevertheless, the possibility is remarkable.
Human beings typically experience the ocean through relatively brief visits: a beach holiday, a fishing trip, a research expedition, or a few decades spent studying marine life.
A Greenland shark may experience the same broad marine environment across centuries of change.
It could outlive the scientists who study it, the fishing vessels that pass through its habitat, and many of the technologies used to observe it.
This is one reason the species has captured the public imagination. It offers a rare glimpse of longevity on a scale that makes even a long human life seem brief.
And because these sharks live in places that humans rarely see, there may be much more to learn about the oldest individuals in the population.