Which animal is the longest-lived vertebrate known to science, with one individual estimated at nearly 400 years old?
- The bowhead whale
- The Greenland shark
- The Galápagos giant tortoise
- The koi carp
Why B? And why not the others?
Correct answer: B. The Greenland shark
A 2016 study in the journal Science radiocarbon-dated proteins locked inside Greenland sharks' eye lenses — tissue formed before birth and never replaced — and found lifespans of at least 272 years, with the largest female estimated at 392 years, give or take a century. These Arctic deep-water sharks grow only about a centimetre per year and may not reach sexual maturity until around age 150. The bowhead whale is a strong runner-up: at over 200 years it is the longest-lived mammal, but not the longest-lived vertebrate. Galápagos giant tortoises are the classic longevity icon, yet their well-documented ages top out around 175 to 190 years. The koi carp owes its spot here to the famous story of 'Hanako,' a fish claimed to be 226 years old — a charming tale whose scale-ring dating has never been scientifically substantiated.
Source: Nielsen et al., Science (2016): eye lens radiocarbon reveals centuries of longevity in the Greenland shark; NOAA Ocean Service