COLD OPEN+ · NATURE
COLD OPEN+ · Nº 27 of 40
A Shark Older Than Shakespeare
Greenland sharks can live for centuries. Some swimming today may have been born around 400 years ago.
Wikimedia Commons · Diego Delso · CC BY-SA 4.0
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THE ANIMAL
The Greenland shark
A large, slow shark that cruises the frigid deep waters of the North Atlantic and Arctic. For a long time nobody knew how old they got — their bodies lack the usual growth structures scientists use to count years.
Wikimedia Commons · Mfield, Matthew Field, www.photography.mattfie… · CC BY-SA 3.0
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THE DISCOVERY
~400
YEARS — THE UPPER LIFESPAN ESTIMATE (2016 STUDY)
The longest-lived animals with a backbone
In 2016, scientists dated chemical layers in the sharks' eye lenses and estimated some individuals were roughly 300 to 400 years old — making Greenland sharks the longest-lived vertebrates known to science.
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THE MATH
Born before your country
If the top estimates hold, a Greenland shark swimming today could have been alive in the 1600s — older than most nations, older than the light bulb, older than nearly every book on your shelf.
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THE SECRET
Slow everything
Their long life comes from living in the slow lane.
COLD
Frigid water slows their metabolism to a crawl
SLOW
They swim at a gentle, unhurried pace
PATIENT
They grow only about a centimeter a year
LATE
They may not reproduce until around age 150
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THE CATCH
Long life, slow recovery
Living for centuries and breeding late means these sharks bounce back from harm painfully slowly. An animal that takes ~150 years to reach maturity cannot recover quickly if its numbers fall.
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THE TAKEAWAY
Some living things run on a clock we can barely comprehend.
A single Greenland shark can watch centuries pass. It's a reminder that 'a lifetime' means wildly different things across the living world.
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THE RECEIPTS · THIS REALLY HAPPENED
Look it up yourself
Published in the journal Science.
SPECIES
The Greenland shark (Somniosus microcephalus)
THE STUDY
Published 2016
METHOD
Radiocarbon dating of the eye lens
ESTIMATE
Roughly 300–400 years old
RECORD
Longest-lived vertebrate known
MATURITY
Reached at around 150 years
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DISCUSS
What do you think?
How do you even measure the age of an animal with no growth rings?
What responsibility comes with sharing the planet with 400-year-old animals?
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