Oldest mammal
Who
Bowhead whale, Balaena mysticetus
What
211 year(s)
Where
Not Applicable ()
When
1999

The longest-lived species of mammal is the bowhead whale (Balaena mysticetus), a baleen (toothless) species that is exclusively native to Arctic and subarctic waters. On 16 May 2007, during a legal whaling hunt off Alaska, USA – as part of a subsidence programme endorsed by the International Whaling Commission – a group of Inupiat Eskimos reeled in a bowhead with a fragment of an antique harpoon embedded in its neck blubber. The weapon used to be manufactured in New Bedford, Massachusetts, USA, during the time when this species was heavily hunted commercially in the late 19th century; the specific model was patented in 1879. Given the narrow window of time in which the projectile is believed to have been fired, scientists estimated this specimen to be approximately 115–130 years old in 2007. Even older bowheads have been estimated in other research. A 1999 study of amino acids in eye lenses (a process known as AAR, or aspartic acid racemization) was carried out by Craig George of the North Slope Borough Department of Wildlife Management in Alaska, USA, and geochemist Jeffrey Bada of the Scripps Institution of Oceanography in California, USA. Of the 48 samples studied – taken from whales that were hunted between 1978 and 1997 – most were assessed to have been aged between 20 and 60 when they died. However, five superlative individuals were estimated to be 91, 135, 159, 172 and 211 years old. Given the accuracy range of this ageing technique, they suggest that the 211-year-old could have been anywhere from 177 to 245 years old.


It’s worth noting that some scientists are dubious about the accuracy of the AAR technique, casting doubt on the proposed older whales – particularly the 200-year-plus specimen.

A team of scientists from Liverpool University, UK, successfully sequenced the entire genome of this species, in the hope of discovering genetic clues regarding its exceptional lifespan. Team leader Dr João Pedro de Magalhães believes that several different factors are collectively responsible for its extreme longevity: "Large whales like the bowhead have few natural predators which allows them to evolve a life history strategy of slow growth and delayed reproduction and also evolve natural mechanisms that suppress age-related diseases and degeneration”.