Bowhead Whale is the longest lived mammal on Earth

The bowhead whale can live over 200 years old, and it is the longest-lived mammal on Earth.
Scientists  have checked the sequence of the genome of the bowhead whale, against that of other
shorter-lived mammals.

Observations showed that bowhead whales have genetic differences unique to their species. For
example, genetic alterations related to cell division, DNA repair, cancer, and ageing may have
helped increase its lifespan and helped it to avoid contracting diseases associated with old age.

Some large whales like the bowhead have over 1,000 times more cells than humans do.  It is
thought that this natural mechanism is responsible for the animal's cancer resistance.

Also, whale cells have a much lower metabolic rate than those of smaller mammals. Changes have
been found in one gene that is involved in thermoregulation, and this may also have an effect
on metabolic rate, and hence ageing.

Bowhead whales are also one of the heaviest animals on Earth, of the heaviest, reaching 100 tons
, which is second only to the blue whale. There are thought to be 7000-10000 of them living mainly in cold waters of the Arctic.