What is the oldest animal on Earth?



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It is difficult to determine which animals live the longest, as some play with the system. Immortal jellyfish, for example, clone themselves in the juvenile polyp stage, a stage to which they can return later in life. It’s a jaw-dropping feat, but is it the same jellyfish or a newborn copy?

Another flaw is suspended animation. According to a recent study in Current biology, scientists thawed microscopic rotifers – which had been in a state of cryptobiosis in Siberian permafrost for 24,000 years – which began to reproduce asexually as if it was their morning routine.

With those outliers in mind, here are the animals that are likely to get the most free Baskin-Robbins Birthday Balls in their very long lifetimes.

1. Deep sea sponges // 2300-18000 years

A kind of deep sea glass sponge (Monorhaphis chuni) produces an extremely long spicule, or skeletal structure, of silica, with the sponge part on top. It looks a bit like an artistic floor lamp. Like tree rings, silica layers record climatic fluctuations as well as the age of the animal. A 2017 study of ocean composition over time that included Mr. chuni the spicules estimated they were between 5,000 and 18,000 years old.

In 2008, another study investigating the growth rate of the giant barrel sponge (Gestopongia muta) estimated that they can live over 2,300 years.

2. Greenland shark // 400-500 years old

Although slow and usually blinded by eye parasites, Greenland sharks (Somniosus microcephaly) are still one of the Arctic’s top predators and the world’s longest-lived vertebrates. A 2016 study of a 16-foot Greenland shark, which was caught in fishing nets as bycatch, used a new technique to date the animal. By radiocarbon dating a protein inside their eyes, which forms before birth and remains viable throughout their lives, scientists estimated the specimen to be around 392 years old, plus or minus 120 years old. This suggests that sharks can live between 272 and 512 years.

3. Ocean Quahog // 200-500 years

Those cold water clams (Arctica islandica) often live well beyond 200 years [PDF]. The oldest known individual was a 507-year-old adult named Ming the mollusk, collected by researchers from the Icelandic plateau in 2006. The age of the clams is determined by counting the lines on the shell, some of which are extremely fine, and that of Ming’s actual age was only determined in 2013 by researchers at Bangor University in the UK. The animal would have been born in 1499, at the time of the Ming dynasty, hence its nickname.

4. Bowhead whale // 200 years

Analysis of stone harpoon points found in bowhead whale fat (Balaena mysticetus) is one of the ways in which scientists determined that they could live up to two centuries. Biologists working with native whalers in northern Alaska have found encrusted harpoon points believed to date from the 1890s. Scientists also analyzed eye tissue from a group of bowhead whales and concluded that one of the animals was 211 years old at the time of its death. Bowhead whales, named for the large curvature of their arcuate mouths, are one of 14 species of baleen whales and the only one that lives in the Arctic year-round.

5. Redfish // 100-200 years

Some species of the genus Rockfish live to 100-200 years (if they don’t end up on someone’s plate first.) Rockfish do not begin to reproduce until around 25 years of age; their late flowering and slow growth make them vulnerable to overfishing.

6. Red sea urchin // 100-200 years

Red sea urchins (Strongylocentrotus franciscanus) look like living Koosh balls, eat mostly kelp, and never pay attention to their appearance for their age. They can live up to 200 years, and in addition to growing a little more each year, they show no signs of aging – they even retain their reproductive abilities. They can die from being eaten, caught or from a specific disease, but very rarely (if at all) from old age.

7. Aldabra giant tortoise // 189 years and over

If this list noted the most famous long-lived animals, the giant Aldabra tortoises (Aldabrachelys gigantea) would surely be on top. On the island of St. Helena in the southern Atlantic Ocean, a Seychelles giant tortoise (a subspecies of Aldabra) named Jonathan currently holds the Guinness World Record for the oldest land animal at 189 years old and more. Jonathan was born in 1832, when Charles Darwin was still three years from his arrival in the Galapagos.



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