WASHINGTON – Great white sharks may live into their 70s, more than three times longer than previously thought, according to a new analysis of the marine predator’s backbones out Wednesday.
Using radiocarbon dating technology, researchers analyzed vertebrae from four male and four female adult white sharks from the northwestern Atlantic.
The largest male was 73 years old and the largest female was 40, according to the report by scientists at Woods Hole Oceanographic Institution (WHOI) in Cape Cod, Massachusetts.
“Our results dramatically extend the maximum age and longevity of white sharks compared to earlier studies,” said Li Ling Hamady, lead author of the study, published in the journal PLOS ONE.
Previous research on growth bands — which are similar to rings in trees that signify age and growth — in sharks’ bones presumed that each band was equal to about a year.
By those steps, the oldest white sharks ever found were a 22-year-old from the Southwestern Pacific and a 23-year-old from the Western Indian Ocean.
However, the latest study measured their ages by looking at their bones for radiocarbon residue from nuclear tests done by the United States and Soviet Union during the 1950s and 1960s.
Bomb carbon from these tests, which were banned after 1963, got into the atmosphere and sea.
Sea creatures incorporated the radiocarbon into their tissues, offering a sort of time stamp to help determine the ages of those that lived during the thermonuclear tests.
The bones studied came from sharks caught in the northwestern Atlantic from 1967 to 2010.