OceanPolar Seas
Greenland sharks are aged by radiocarbon in the centre of the eye lens, which is laid down before birth and never replaced.
The oldest measured were roughly four centuries old.
Source
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More ocean facts
Ocean facts from a place we have mapped less thoroughly than Mars. A male anglerfish merges with his mate for good, there are lakes at the bottom of the ocean, and below about 8,400 metres there are no fish at all. Each fact links to its source.
- Antarctic icefish have no haemoglobin.
- For years the loudest unexplained noise ever recorded underwater fuelled talk of an unknown sea creature.
- A male anglerfish merges with his mate. Permanently.
- Sensitive instruments are still built from steel salvaged off warships sunk before 1945.
- The Mediterranean dried to salt flats around five million years ago.
- There are lakes at the bottom of the ocean.