Spell It: Meet the longest-living animals on Earth

Have you ever wondered just how old is the oldest animal on Earth?

Click start to play today’s Spell It, where we discover ageing animals in a ‘league’ of their own.

A study published in May 2021 in the journal Nature Communications estimated the absolute limit of human lifespans – 150 years. Yet, this duration is just a blink of an eye compared to the millennia that some animals live through.

Here are five of the longest-living animals in the world today:

1. Hydra: Potentially immortal

A small group of invertebrates, hydra resemble jellyfish and have the potential to live forever. Made primarily of stem cells, they continuously regenerate through cloning, so they don’t really deteriorate like other animals do. Hydra can die because of predators or disease, but if they were left alone, no one could stop them from regenerating for posterity.

2. Turritopsis dohrnii: Potentially immortal

Another creature with the ability to live forever, Turritopsis dohrnii is known as the ‘immortal jellyfish’. Jellyfish start their lives as larvae, before transforming into invertebrates called polyps on the seafloor. The polyps go through another life cycle change and transform into jellyfish. In the case of T. dohrnii, these jellyfish can turn back into polyps if they experience physical damage or starvation, according to the American Museum of Natural History. Once they are healed, they can return to their jellyfish state again. Native to the Mediterranean Sea, these jellyfish are less than 4.5mm across, so they’re hunted by many predators, such as fish, often thwarting their plans to live forever.

3. Glass sponge: Over 10,000 years

Like corals, sponges comprise colonies of animals, and they can live for over 10,000 years. Glass sponges can be found in the deep ocean and are named as such because their skeletons resemble glass. A 2012 study in the journal Chemical Geology estimated that a glass sponge from the species Monorhaphis chuni was about 11,000 years old. Other sponge species are thought to live even longer.

4. Black coral: Over 4,000 years

Although they look like vibrant plants or rocks, corals are made up of the exoskeletons of polyps, which keep multiplying and replacing themselves with an identical copy. This regeneration allows the coral structure to grow bigger and bigger over time. Black corals, which live in deep water, are among the longest-living corals. Specimens found off the coast of Hawaii have been radiocarbon-dated to be 4,265 years old.

5. Ocean quahog clam: Over 500 years

This saltwater species lives in the North Atlantic Ocean, and is known to have slower metabolism because of the colder water surrounding places like Iceland. Ocean quahog clams grow very slowly. One clam found off the coast of Iceland in 2006 was found to be 507 years old, according to the National Museum Wales in the UK. It was nicknamed Ming since it was born in 1499 – a time period in which, the Ming dynasty ruled China. There could be even older clams in the ocean, scientists surmise.

What do you think of these incredible creatures? Play today’s Spell It and tell us at games@gulfnews.com.