Animals living under natural conditions rarely approach their maximum possible age because of very high death rates due to infant mortality, diseases, predators, bad weather, habitat destruction, or competition for food and shelter. Here we list ten animals that would have the longest lifespans living under ideal circumstances.
10. Macaw
Recognisable by their brightly covered feathers, macaws are members of the parrot family. They have a long lifespan and, in the right environment, will live to be 60 to 80 years old. There are at home in the rainforests and feed on a mix of nuts and seeds. Unfortunately, though, the majority of these beautiful birds are endangered in the wild and a few are already extinct due to habitat degradation and the illegal pet trade.
9. African Elephant
African elephants are the largest living land animals and, with an average lifespan of 70 years, one of the oldest. Experts are able to tell the age using several characteristics including their size and number of teeth. It’s a process that requires observational skills and a lot of practice!
Females reach breeding age around 10-12 years old and, unlike us, they may remain fertile for the rest of their lives. They may give birth to around 7 babies in total. Being a mummy elephant is no easy task though. Their pregnancy lasts 22 months, which is almost three times as long as a human pregnancy! Read more about elephants.
8. Longfin Eel
Longfin eels typically live up to 60 years old though the longest living on record reached 106! They are native to New Zealand and Australia and spend most of their life hiding in freshwater streams before migrating to the Pacific Ocean to breed. They only do this once in the lifetime and die after spawning. They are very slow-growing animals, growing only 1-2cm a year, but females eventually grow to an impressive 73–156 cm in length.
7.Galapagos Giant Tortoise
It’s not just the Galapagos Giant Tortoise size that’s worth noting; it’s also their age. They can live to be well over 100, with the oldest known to be 152! The oldest is not the most famous, though. Lonesome George was the last remaining Pinta Island Tortoise on the islands and, for a while, the world’s rarest creature. He died in 2012 at around 100 years of age. Like many of the animals on our list, giant tortoises have a slow pace of life, munching on grass and other vegetation, basking in the sun and resting for up to 16 hours a day.
6. Red Sea Urchin
Red sea urchins are believed to be almost immortal and are known to live for over 200 years with no signs of ageing. They are far more likely to be eaten by a predator than die of an age-related condition, and a 100-year-old is just as healthy and able to reproduce as a young individual. Finding the age of these spiny echinoderms is possible by measuring the levels of carbon-14, a process known as radiocarbon dating.
5. Koi Fish
The average lifespan for Japanese Koi is around 40 years though they can live a lot longer if living in the right conditions. One particular koi, named “Hanako”, was the remarkable age of 226 when she died in 1977. Scientists were able to estimate her age by counting growth rings in her scales.
4.Bowhead whales
Bowhead whales can live for over 200 years, which is longer than any other mammal. It’s not always easy to tell their age, though, as they spend their lives in the Arctic and sub-Arctic and can outlive the researchers that study them. One way to estimate age is to base it on fragments of harpoons left in the blubber of captured animals – one individual had harpoon fragments dating back to the 1800s! Another way is to use DNA to estimate lifespan, with scientists suggesting bowhead whales can live to the grand old age of 268!
3. Greenland Shark
Greenland sharks live for between 300 and 500 years and are the longest-living vertebrate. They take life very slowly, moving at an average of 0.76 mph. They grow about a cm every year, and females may not reach sexual maturity until they are 100 to 150 years old – that’s one long childhood! Despite their huge size and long lifespan though, these sharks have been a mystery to scientists for years. It was only recently that they discovered a new method of estimating age that involves radiocarbon dating the lens of the eye. New tissues are added to the lens every year and it is possible to tell the age by how much carbon isotope is present in the tissues.
2. Ocean Quahog
Ocean Quahogs are an edible clam with an impressive lifespan. Many will live to see their 400th birthday and the oldest one on record was 507 years old when it was caught off the coast of Iceland in 2006. Scientists were able to determine the age by counting growth rings on the shell, similar to how we age trees. They can also find out other information too. How the shells form over time tells scientists how the oceans have changed throughout the years – they are a living creature and a picture of life in a changing world!
1. Immortal Jellyfish
Can you imagine being immortal? Reaching old age and then instead of dying, going back and starting again as a baby? To us, this is the stuff of dreams. For the immortal jellyfish, it is real life. These amazing animals start their life as larvae, known as planula, swirling around in the ocean. They then settle on the seafloor and become static polyps before transforming into swimming medusa. So far, so normal. But, if at any stage immortal jellyfish experience injury or stress from changes in their environment, they can go backwards to the polyp stage and start again. And they can do this over and over if they get the chance. Many won’t though as they become dinner for other animals.
