When animals have a slow metabolic rate, they do not age but rather have a prolonged life. Resistance to diseases and genetics are also factors that can contribute to the longevity of an animal.
Having fewer offspring and prioritising survival are what some animals do to remain alive.
Below are the longest living animals on Earth as listed by Kilimanjaro:
1. Immortal Jellyfish (Forever)
The immortal jellyfish is a type of fish that lives forever. It can reset its life cycle or transform its adult cells into young cells. This process is referred to as “transdifferentiation.” Immortal jellyfish start a new life as a larva, then develop into a polyp — which can birth many jellyfish through asexual reproduction. The immortal jellyfish is usually found in the Mediterranean sea and the coast of Japan.
2. Antarctic Glass Sponges (15,000 years)
Antarctic glass sponges live in deep waters and the Antarctic Ocean. They can live up to 15,000 years which makes them the second longest living animal on Earth. They have a slow metabolism; they don’t age.
3. Black Corals (4,000 years)
Black corals can be found in oceans and they live up to 4,000 years. Their name comes from their skeletons which are either black or dark. These skeletons are made up of hard materials. Black corals are in various colours which include yellow, red, green and white.
4. Ocean Quahogs (500 years)
Ocean quahogs live in the North Atlantic Ocean. It takes several years before they mature. Their longevity is due to slow metabolism; they grow a few millimeters per year and can live for over 500 years.
5. Greenland Sharks (500 years)
Greenland sharks dwell in cold waters. They are slow and large; their length can reach 7.3 metres. Greenland sharks grow at a slow rate and reach sexual maturity at around 150 years. You can find them in the North Atlantic and Arctic Ocean and they live for about 500 years before death.
6. Freshwater Pearl Mussels (280 years)
Freshwater pearl mussels are found in fast-flowing clean rivers in North America and Europe. They produce pearls, although not commercially available as those of marine oysters. During fertilization, females release larvae that get attached to the fins of a host fish (which could be trout or salmon) to produce; then develop into adult mussels.
7. Koi Fish (220 years)
Koi fish are mostly found in Japan and China. In Asian culture, they symbolize prosperity, good fortune and luck. They are the domesticated version of common carp. Koi can live up to 220 years. They can also be kept in ponds.
8. Rougheye Rockfish (205 years)
Rougheye rockfish are fish found in the North Pacific Ocean. They love associating with underwater structures such as boulders and reeds. These fish can weigh up to 14 pounds, grow up to 38 inches and live up to 205 years. Rougheye are slow to mature.
9. Red Sea Urchins (200 years)
Red sea urchins have reddish-brown shells that protect them from predators. They can be found in the Pacific Coast of North America. They live for about 200 years and are used for delicacies in Japan.
10. Bowhead Whales (200 years)
Bowhead Whales are usually spotted in the Arctic and sub-Arctic regions. As one of the longest living animals in the world, they weigh between 75 and 100 tons. They are also one of the largest whales — which helps them survive harsh environments. They consume crustaceans and some other plankton organisms.
