The Greenland shark , Somniosus microcephalus , is the foresighted - living vertebrate on the major planet with a lifespan that ’s thought to peradventure extend beyond 500 years . Even at the most buttoned-down appraisal of 272 years , it beats any other metal money on Earth – but the way we came to discover their uttermost length of service begins with the atomic bomb calorimeter .
Aging Greenland sharks is unmanageable because they lack the calcify tissues researchers sample when canvas things , like theear stonesof Fish , which can reveal geezerhood a act like growth ring in a tree . To overcome this obstruction , researchers in a2016 studyused carbon 14 dating techniques to inquire the eye crystalline lens of Greenland sharks .
The eye lenses of 28 female Greenland sharks were study to test for their radiocarbon level and stable isotope , which are dictate by the diet of the shark ’s female parent rather than the sampled animal . This is because of the unique fashion in which heart lens retain some structural detail that were present on the first day of the shark ’s life .
The mushroom cloud from the Castle Bravo thermonuclear weapon test in 1954, the largest nuclear weapons test ever conducted by the United States.Image credit: United States Department of Energy - National Oceanic and Atmosphere Administration, Public Domain, via Wikimedia Commons
“ In craniate , the heart lens nucleus is composed of metabolically neutral crystalline protein , which in the center ( i.e. , the embryologic nucleus ) is make during prenatal development , ” explain the author . “ This tissue hold back protein synthetized at approximately age 0 : a unique feature of speech of the optic genus Lens that has been work for other difficult - to - years vertebrate . ”
Where an atomic blast number into this is a phenomenon have sex as the “ turkey pulse ” that ’s been identified as an indicator of nautical brute ’ ages because of the elbow room it influences the radiocarbon levels , as enormous amounts of the radioactive isotope C-12 and C-14 were liberate into the surround .
“ Since the mid-1950s , turkey – grow carbon 14 from atmospherical tests of thermonuclear weapons has been take in in the marine environment , creating a distinct ' turkey pulse ' in carbon - found chronologies , ” explained the generator . “ The period of time of speedy carbon 14 gain is a well - establish time stamp for age validation of maritime animals . ”
The unnaturally high stage of carbon 14 were incorporate into the tissue of all living affair born after the bomb pulse , acting as a biomarker for long time as the tissue of animals carry beforehand look very different in radiocarbon go steady terms . For ourGreenland sharks , that meant the highest amounts of radioactive isotope were found among the centre lens of the eye of the youngest shark .
For the remaining large sharks , modeling break the average lifetime to be at least 272 class , though the with child ones were estimated to be nearer to 335 and 392 old age honest-to-goodness . The squad also gauge their historic period at sexual adulthood to be 156 years old , making for a earnestly foresightful adolescence .
Part of the understanding for these bass - sea giant ’ unbelievable longevity is the extremes of cold they live in . The Arctic environs yell for a in earnest dense metabolism , something that’sassociated with longevityin a range of brute groups .
While an telling track record , as the researchers warned , Greenland shark ’ unbelievably long lifetime and the metre it takes for them to reach intimate maturity also make them vulnerable , as every animal of procreative age represent a monumental investing in terms of years spent on Earth .
“ Our estimates strongly suggest a precautionary approach to the preservation of the Greenland shark , because they are vernacular by-catch in arctic and subarctic groundfish fisheries and have been subjected to several late commercial exploitation initiatives , ” they conclude .
400 years is moderately impressive , but theocean quahogstill has the Greenland shark beat .
