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  • Writer's pictureWill Hedrick

Why a 400-Year-old Shark & 507-Year-old Clam can live so long

In August 2016, scientists gathered data from 28 female Greenland Sharks (Somniosus microcephalus). Their research determined a lifespan of at least 272 years old, with estimates reaching up to 512 years old.

In 2006, scientists were dredging in Iceland and eventually found Ming. Ming is the oldest living animal ever recorded at 507 years old.

Here is what we know about these species and why they live so long.


Greenland Shark

The Greenland Shark is no small shark. They can reach sizes up to 23 feet and weigh almost 2,300 lbs. Greenlands are found commonly in cold water environments like the Artic Ocean and North Atlantic, but occasionally stretch their range by visiting the eastern states of The United States. While traveling down the more populated Eastern Seaboard, humans will rarely see the sharks. Greenland Sharks reach depths of about 7,200 feet - over a mile deep. The first photograph of a Greenland Shark was taken in 1995.


Throughout the 19th century, Greenland sharks were commercially fished. As many as 30,000 Greenlands were caught every year. Their liver oil was valuable, and over 30 gallons could be extracted from a larger shark. Today, the Greenland Shark commercial fishing has been slowed as populations have dwindled. The IUCN lists Greenland Sharks as Vulnerable - with a population decreasing in numbers.

In August 2016, scientists gathered data from 28 female Greenland Sharks (Somniosus microcephalus). Their research determined a lifespan of at least 272 years old. However, scientists also estimated during their study that some of the largest sharks could be reaching ages up to 512 years old (give or take 120 years for their estimates).


Most shark species can get their age estimated by counting "growth bands" on the fins and vertebrae of their spine - somewhat similar to trees when cut down. However, Greenland sharks do not have hard tissue in their body, making determining their age much more difficult.

Scientists can get these estimates through radiocarbon dating of the lenses in the shark's eyes. Nielsen tracked amounts of Carbon-14 produced by nuclear tests in the 1950s to estimate the Greenland Sharks' age. Quite remarkable science if you ask us.


We know that these sharks live for so long, but why?

One theory that scientist believes contribute to Greenland Sharks living for so long is their slow metabolism. They are slow to grow and age and are extremely slow movers - Greenlands typically swim around 1 foot per second (they can move quickly for short bursts when chasing prey).


Ming the Ocean Quahog Clam

Alan D Wanamaker Jr1, Jan Heinemeier • James D Scourse • Christopher A Richardson1 • Paul G Butler • Jón Eiríksson • Karen Luise Knudsen, CC BY 3.0 <https://creativecommons.org/licenses/by/3.0>, via Wikimedia Commons


The Ocean Quahog Clam - the species of clam that 507-year-old Ming was, is commonly found in the North Atlantic ocean. They are bivalves, meaning they have two external coverings, their shells, that open and close on a hinge in the back. These shells are thick and oval-shaped, with rings along them that are similar to trees are counted to determine the age of the mollusk.

The Ocean Quahog is commercially harvested. NOAA estimates that 15 million pounds of meat were harvested from their fisheries in 2021. However, unlike the Greenland Sharks, NOAA notes that they are above the targeted population level and fishing operations are at their recommended level.

When Ming was born, Leonardo Da Vinci worked hard on the Mona Lisa, and the Ming Dynasty ruled China - hence the name. Ming was collected from the Icelandic shelf, and scientists for experiments dredged 200 or so other specimens. Ming gained a large following after their research was conducted, as the scientists killed all of the clams by freezing them on board to take them home for research. They didn't realize how remarkable their findings were yet.


Initially, they believed Ming was to be 405-410 years old. The bands that grew on the shell to show age were so close together that it was hard to tell. However, later radiocarbon dating showed that "is "pretty much without error.""


Bangor University in Wales believes these clams have evolved in such a way that has allowed them to reach such extraordinary ages.


Evolution has created a model of successful resistance to the damage of ageing, it is possible that an investigation of the tissues of these real life "Methuselahs" might help understand the processes of ageing in a range of organisms, including humans.

Conserving Greenland Sharks

While we work to learn more about the Greenland Shark, we need to ensure plenty are alive in the wild. As we mentioned, the IUCN lists Greenland Sharks as Vulnerable - with a population decreasing in numbers. The threats to Greenland sharks are primarily from bycatch and fishing incidents, something our extraordinary partners at The Shark Trust know well.

The Shark Trust is a UK-based non-profit organization creating positive change for sharks. Shark Trust focuses on three conservation goals, species protection, fisheries management, and responsible trade. Outside of their conservation goals, they recognize shark conservation is driven by four agents of change, government, industry, scientists, and non-profits/NGOs.

They have engaged in numerous notable achievements including the landmark EU Finning Regulation (2013), regional action plans for critically endangered angel sharks and catch limits on Blue and Mako Sharks in North Atlantic fisheries. We are excited to be working with such an extraordinary organization that is blazing an impressive trail for shark conservation.


Donate and learn more about our Shark Conservation Project by clicking here.

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