What is the longest living animal?
Among vertebrates, the Greenland shark lives longest, possibly about 400 years. A quahog clam named Ming lived 507 years, and some sponges and corals live thousands of years.
In 2016, scientists estimated the age of Greenland sharks using carbon dating of the lenses in their eyes. The oldest shark studied was likely between about 270 and 500 years old. These sharks grow only about a centimeter a year and live in cold Arctic waters.
An ocean quahog clam collected off Iceland in 2006 turned out to be 507 years old after scientists counted the growth lines on its shell. Bowhead whales, the longest-living mammals, can reach more than 200 years.
Nearly immortal creatures
Some animals do not age in the usual way. The so-called immortal jellyfish can turn back into an earlier life stage when stressed. Some deep-sea sponges and black corals are believed to be thousands of years old.
Did You Know?
The oldest known land animal is a Seychelles giant tortoise named Jonathan, who lives on the island of Saint Helena and is thought to have hatched around 1832.