The new research, he says, is the first hard evidence of just how long these creatures can live.
“It definitely tells us that this creature is extraordinary and it should be considered among the absolute oldest animals in the world,” said Nielsen.
Writing in the journal Science, Nielsen and an international team of researchers describe how they set about determining the age of 28 female Greenland sharks, collected as by-catch during scientific surveys between 2010 and 2013.
While the ages of many fish can be determined by counting the growth layers of calcium carbonate “stones” found in their ears – in a manner somewhat similar to counting tree rings – sharks do not have such earstones. What’s more, the Greenland shark lacks other calcium-rich tissues suitable for this type of analysis.
Instead the team had to rely on a different approach: scrutiny of the lenses in their eyes.