An international study published in Science in 2016 revealed that a Greenland shark could be nearly 399 years old, making it the longest-lived vertebrate ever recorded.
The specimen would have been born approximately in 1627, during the colonial era, and was identified thanks to the analysis of 28 sharks incidentally captured by fishermen in Arctic waters.
Scientific Method
To determine the age, researchers applied an innovative procedure:
Radiocarbon dating of eye lenses, a tissue that does not regenerate after birth.
Comparison with historical carbon levels to estimate when that tissue was formed.
The results were surprising: the average age of the specimens was 272 years, and the largest, over 5 meters, would reach 399 years.
Reasons for its Longevity
The extraordinary lifespan of this species is explained by several factors:
Slow growth: barely 1 cm per year.
Late sexual maturity: they reach adulthood around 150 years.
Low metabolism, adapted to near-freezing temperatures.
Deep and stable habitat, more than 2,000 meters deep.
Recent research suggests they possess genetic DNA repair mechanisms, granting them resistance to aging and diseases.
The Greenland shark has proven to be incredibly long-lived.
Unique Characteristics
The Greenland shark is a fascinating animal:
It can measure up to 7 meters and weigh more than 1,000 kilos.
Swims slowly, at less than 2 km/h.
Feeds on fish, seals, squids, and organic remains.
Is ovoviviparous, with infrequent reproduction.
Its slow-paced lifestyle and extreme habitat make it a unique species in the marine world.
Current Threats
Despite its survival capabilities, it faces increasing risks:
Incidental fishing, which accidentally captures it in nets.
Climate change, which alters Arctic conditions.
Marine pollution, which affects the quality of its habitat.
The combination of these threats endangers a species that has survived for centuries in the ocean depths.
A Witness to History
If the estimates are correct, this shark would have been born in 1627, when Galileo was still studying the skies and before Newton formulated his laws. It has survived revolutions, world wars, and technological transformations, remaining hidden in the icy waters of the Arctic.
The Greenland shark is more than a long-lived animal: it is a symbol of resilience and a reminder of the biological richness we still do not know. Its existence raises questions about the limits of life and the importance of protecting marine ecosystems against human threats.