Bowhead sharks can live up to 500 years, the period of puberty in females comes after 150 years, this is the conclusion reached by scientists from the University of Copenhagen. The habitat of the Greenland shark (Somniosus microcephalus) is the North Atlantic and the cold surface waters of the Arctic, reports the New Scientist.
This species of fish that lived during the age of Enlightenment, still swims in the ocean. Until now it was known that the Greenland shark lives at least 272 years, being the most long-lived vertebrates in the world. She broke thus the previous record life expectancy 211 year-old bowhead whale.
But the Greenland shark can live 500 years.
“We definitely expected the sharks will be old, but we didn’t expect them to be the most long-lived vertebrates,” said Julius Nielsen, University of Copenhagen, Denmark.
Living deep in the North Atlantic and the cold surface waters of the Arctic, Greenland sharks have a stable environment and grow only a few centimeters per year. Despite the slow growth, these predators reach more than 5 meters in length and often cover the top of the food chain.
Nielsen and his colleagues have tried to clarify the lifespan of the Greenland shark. It was used by the part of the spine sharks living in the waters of Greenland in the North Atlantic. To determine the age of sharks, scientists have used radiocarbon analysis. The samples were made by the lens of the eyes of Greenland sharks caught in the region previously.
Radiocarbon analysis was aimed at identifying in the body of sharks of radioactive particles that remained after the atomic bomb tests in the mid-1950s and early 1960-ies.
These particles entered the food chain in the world and there are radioactive forms of carbon in organisms that survived the period of nuclear bomb tests. Since the tissue of the lens of the eye of the Greenland shark does not change during the entire lifetime of the animal, it retains the historical radiation.
After catching sharks with a length of 2.2 meters, which showed the radiation level, indicating that the shark was born in 1960-ies, researchers have built the curve of growth to determine the age of other individuals, depending on the length of the body.
According to estimates by teams of scientists, one five-meter animal was at least 272 years, but it’s possible that his age exceeds 500 years (392 years plus or minus 120 years). Another animal had age at least 260 years and could be older than 400 years.
Female sharks probably do not reach breeding age until they live about 150 years.
According to the authors, this indicator of longevity can contribute including low water temperatures, which inhabit the Arctic shark. Such conditions allow to slow down their growth and biochemical processes of the body.
