Jonathan, the 190-Year Old Tortoise Teaches Us About Aging
Meet Jonathan, a giant tortoise, the world’s oldest living land animal. He was hatched in 1832 which makes him 190 years old – Andrew Jackson was in the White House and the first shot of the Civil War was still 19 years away.
Jonathan’s age has recently made him a celebrity: when Guinness World Records announced his longevity status, rock star publicity put Jonathan in the international spotlight. Newspapers, magazines, and even CNN came calling.
The 440-pound tortoise spent the first 50 years of his life on the Seychelles Islands in the Indian Ocean, just east of Africa. For the last 140 years, Jonathan has been wandering the grounds of the governor’s residence on the tropical volcanic island of Saint Helene in the South Atlantic Ocean.
Jonathan arrived at Saint Helene in 1882 as a gift for Sir William Grey-Wilson, a future governor. Prior to the Guinness announcement, Saint Helene had been chiefly noted for being home to the exiled Napoleon who died there in May of 1821 (for the record, he was only 51 at the time of his passing).
Saint Helene is commemorating Jonathan’s birth throughout 2022 — a series of stamps have been issued and royal festivities are set for later this year. Visitors to the remote island are given photos of the tortoise’s footprint.
To date, his newfound stardom has had little impact on Jonathan. He spends most of his time sunbathing, eating (carrots, cucumbers, apples, bananas, and pears), and milling about with the three other tortoises on the property (Emma, David, and Fredrika).
The companionship of the other tortoises is a very important part of Jonathan’s life — they were brought to Saint Helene decades ago when it was determined that Jonathan was lonely. He had begun to exhibit unusual disruptive behavior (turning over benches at nearby tennis courts, sitting on croquet balls so that players were not able to complete matches, etc.). Once the others arrived, Jonathan’s normal behavior resumed.
Joe Hollins, Saint Helene’s first permanent veterinarian, is Jonathan’s chief caretaker.
Calling Jonathan “a great crusty reptile, a gentleman of a tortoise,” Hollins declares the two have developed a strong bond. In a Washington Post interview, Hollins says: “I take great delight in looking after him. It’s a huge responsibility but an honor and privilege for a vet to see to the needs of the oldest known living land animal in the world.”
Hollins’ responsibilities include hand feeding Jonathan, which is sometimes dicey. For protection, Hollins uses welders gloves, but still has lost a fingernail or two. “He’s a prolific belcher,” Hollins adds.
Jonathan, according to Hollins, has achieved fame because he is the ultimate symbol of “persistence, endurance and survival” in today’s fast-paced world.
So, what is it about Jonathan that has kept him alive so long? The answer is biology. Tortoises and turtles belong to a class of species that have “negligible senescence,” a term coined by Caleb Finch, PhD.
Senescence refers to the physical process of growing old: for example, as humans age, our cells stop dividing and gradually harmful tissue accumulates. In Jonathan’s case, cell degradation slows to a standstill — a negligible rate — and that prolongs his life. Jonathan is almost immune to aging.
Rita da Silva, PhD, from the University of Southern Denmark, recently conducted research on turtles and tortoises living in zoos. Seventy-five percent of the subjects showed extremely slow aging. Eighty percent of them demonstrated aging at a much slower rate than humans. “We found that turtles and tortoises have found a way to slow down or even completely switch off senescence,” da Silva said.
The reptiles da Silva studied were not living in the wild. That means the struggles to find food and avoiding predators don’t exist for them. Less stress presumably assists in the slower aging.
As does their diet. Turtles like vegetables and don’t consume those quantities of fat or cholesterol humans do.
But the bottom line is science cannot explain where negligible senescence comes from. Is it an evolutionary luck of the DNA draw? Is it possible for humans to repair and replace cells and tissues that are so damaging? Can we unlock these mysteries?
Ongoing research focused on the role of cellular senescence and the interplay of environmental influences is promising. Researcher Finch has predicted that eventually we will learn how to repair damaged cells: “Negative senescence is a very long-term goal for humans, and (it) means eradication of cancer, heart disease and Alzheimer’s disease.”
Having a healthy quality of life at an advanced age may soon be within our reach. A big thanks to Jonathan for helping to show us the way.