Turtles are known for their remarkable longevity, often living for many decades, and sometimes over a century. This extraordinary lifespan distinguishes them in the animal kingdom, sparking curiosity about the secrets behind their extended existence. The search for the oldest living turtle highlights this fascination, revealing individuals that have witnessed centuries of change. These ancient reptiles represent a unique blend of biological adaptation and historical endurance.
The Current Record Holder
The title of the oldest known living land animal belongs to Jonathan, a Seychelles giant tortoise (Aldabrachelys gigantea hololissa). As of 2025, Jonathan is estimated to be 192 years old, making him the oldest chelonian ever documented. He was hatched around 1832 in the Seychelles and arrived on the remote British Overseas Territory of Saint Helena in the South Atlantic Ocean in 1882.
Jonathan was already considered fully mature upon arrival, suggesting he was at least 50 years old. This age estimate is supported by historical photographs from 1886, showing him as a fully grown adult shortly after his relocation. Jonathan resides on the grounds of Plantation House, the official residence of the Governor of Saint Helena, where he continues to be cared for.
Understanding Turtle Longevity
The exceptional longevity of turtles stems from a combination of biological traits and environmental factors. Their slow metabolism, characteristic of cold-blooded animals (ectotherms), reduces wear and tear. This allows them to conserve energy and endure long periods without food or water. Protective shells also offer defense against predators and minimize injuries, contributing to their survival.
Turtles exhibit remarkable cellular mechanisms that resist aging. They show a lower rate of telomere shortening, protective caps on chromosomes, compared to shorter-lived animals. This cellular resilience helps maintain DNA integrity and function. Some species, including giant tortoises, can also efficiently eliminate damaged cells through programmed cell death, preventing cellular harm. Additionally, stable environments, particularly predator-free islands, play a role in their ability to reach advanced ages.
Determining a Turtle’s Age
Accurately determining a turtle’s age, especially for very old or wild individuals, presents challenges. One common method involves examining growth rings on their scutes, the scales covering their shell. These rings, similar to tree rings, form from new layers during growth spurts, often alternating with slower growth. However, this method provides only a rough estimate. Ring formation can be influenced by environmental conditions like food availability, and becomes less reliable once a turtle reaches maturity, as rings become harder to distinguish.
For captive or semi-captive turtles like Jonathan, historical records, photographs, and eyewitness accounts are crucial for age estimation. These documented observations provide valuable context regarding their size and maturity. While methods like skeletochronology, which examines growth rings in bones, can determine age after an animal’s death, they are not applicable to living turtles. For younger turtles, shell size can offer a general indication of age by comparing it to species-specific growth charts.