The shelled centenarians
As you’ll gather from this feature, many of the longest-lived species have a key thing in common: they live in the ocean – particularly in deep waters. It seems that a marine habitat is simply more conducive to a long life. This probably has something to do with the stable environmental conditions afforded hundreds of metres below the ocean surface, as well as few predators and a slow-paced, or even sessile (stationary) lifestyle.
On land, living to a grand age just seems harder. Us terrestrial animals have to put up with gravity, natural disasters and everchanging weather, as well as leading generally more active lives.
One group of animals that seem to defy the odds are tortoises, giant species of which have an average age of 100. The oldest authenticated age for a chelonian is at least 188 for a Madagascar radiated tortoise called Tu’i Malila, who was presented to the Tongan royal family in the 1770s.
Another ancient example is Jonathan (right), a Seychelles giant tortoise who resides on the Atlantic isle of St Helena and is a strong contender for the oldest living land animal. He was born circa 1832, which means that as of 2018 he could be as old as 186 – so he’s fast (well, slowly) catching up with Tu’i Malila!