Greenland Sharks Live Up to 400 Years Revealed by Radiocarbon Dating

Radiocarbon Dating Reveals Century-Old Vertebrates

The Greenland shark is among the largest carnivorous sharks on the planet and can live for around 400 years, according to research published in Science. Until 2016, marine biologists could only guess at the life expectancy of these little-understood creatures. That year, a research team from the University of Copenhagen applied radiocarbon dating to the sharks’ eye lenses to gather precise age data, establishing a lifespan that makes them the oldest living vertebrate animals known to science.

The Tech TL;DR:

• Marine biologists used carbon-14 radiocarbon dating on eye lenses from 28 female Greenland sharks to calculate their life expectancy.
• Data published in the scientific journal Science revealed the sharks live for at least 272 years, with the oldest estimated at roughly 400 years.
• Researchers found the species reaches sexual maturity at approximately 150 years of age.

Eye Lens Chemistry Unlocks Lifespan Data

The carbon-14 dating technique had previously been used to determine the age of whales, but had never before been applied to estimate the age of fish. The research team examined the eye lenses of 28 female Greenland sharks, which ranged in length from 81 to 502 centimetres. Findings published in the scientific journal Science showed that the animals’ life expectancy reaches a minimum of 272 years.

Julius Nielsen, the lead author of the paper, explained the biological mechanism that made the measurement possible. “As with other vertebrates, the lenses consist of a unique type of metabolically inactive tissue,” Nielsen said, as reported by BBC Wildlife Magazine. “Because the centre of the lens does not change from the time of a shark’s birth, it allows the tissue’s chemical composition to reveal a shark’s age.”

Ecosystem Impact and By-Catch Vulnerability

Data gathered from the lenses indicated that Greenland sharks reach sexual maturity at around 150 years of age, while the largest specimen analyzed was estimated to be approximately 400 years old. Despite their status as some of the largest carnivorous sharks on the planet, their role as an apex predator in the Arctic ecosystem remains largely overlooked by commercial fisheries and environmental monitors.

“By the thousands, they accidentally end up as by-catch across the North Atlantic and I hope that our studies can help to bring a greater focus on the Greenland shark in the future,” Nielsen stated, according to BBC Wildlife Magazine.