Geriatric Jonathan has made headlines again, this time for having his genome sequenced. The Aldabra giant tortoise, estimated at 194 years old, is the oldest known land animal on the planet. (The ocean, which is full of thousands-year-old glass sponges and Greenland sharks that have been swimming for centuries, pushes longevity to different extremes.) As such, it’s understandable that scientists would want to sequence Jonathan’s genome. He lived a very long time.
However, numerous titles announcing this new investigation into the venerable age of Jonathan, published in Scientific advancesmade me laugh with their implications that we might follow in Jonathan’s close footsteps. Consider Reuters: “A 194-year-old turtle, the world’s oldest land animal, may hold clues to longer lives. » Or take The times: “Did the turtle Jonathan, 194 years old, teach us the secret to a longer life?” What are the clues and secrets of Jonathan’s extremely long life? There is mainly one: Jonathan is a turtle.
I can hardly fault these publications for this title format; the plan was featured in press releases issued by the University of Cambridge and Vanderbilt University, both of which presented Jonathan as potentially holding the secret to a long and healthy life, which he very well might do! IFLScience’s headline – “We Finally Know How Jonathan the Turtle, the World’s Oldest Land Animal, Is Still Alive and Kicking at 194” – easily receives the same response. Jonathan the tortoise is alive and well because he was lucky enough to be born a giant Aldabra tortoise. If Jonathan were a human, he wouldn’t be alive.
Turtles, especially giant tortoises, tend to live a long time. Their metabolism is extremely slow, which slows the effects of aging over time and allows animals to limit cell damage. Jonathan’s current longevity record is followed by Esmeralda, a 182-year-old Aldrabra who roams free in the Seychelles. The Aldabra named Adwaita, who lived in a Calcutta zoo, was estimated to be at least 150 years old when he died. Presumably, Jonathan was kind enough to reveal his secret to Esmeralda and Adwaita.
Giant tortoises as a whole live a long time; Harriet, the Galápagos tortoise, was about 175 years old when she died at a zoo in Australia, and the radiated tortoise Tu’i Malila died at about 188 years old, decades after being hit by a horse and run over by a cart. Diva! Icon! Where is his biopic!
The researchers behind the new study suggest that Jonathan lived almost a century longer than the typical lifespan of an Aldabra tortoise. But turtles are difficult to age without a hatch date, which means it’s entirely possible that there are other turtles older than Jonathan. Jonathan, given as a gift to the governor of St Helena 144 years ago, has resided on the island ever since, making his age easily verifiable. It’s also likely that Jonathan’s domesticated lifestyle (he’s a hand-fed turtle with a dedicated care team) helped the turtle survive this long. Although Jonathan feels the weight of his many years, almost blinded by cataracts, he has very good hearing. The turtle loves bananas, has a healthy libido, and is blissfully unaware that earlier this year his death was reported as part of a crypto hoax.
The researchers compared Jonathan’s genome to four other Aldabra tortoises, a 5-year-old named Hatch, a 12-year-old named Smalls, and two adult males named Toka and Poka. They discovered that Jonathan had gene variants linked to aging, such as those involved in telomeres, which are the protective tips at the end of chromosomes that shorten with age. The researchers also looked at the turtle’s epigenome, which are the switches that turn genes on and off, and found that the switches that control Jonathan’s mitochondria were very similar to those in younger turtles. This was surprising because the epigenome tends to change and deteriorate with age. The turtle therefore seems to have fairly stable mitochondria, which is linked to longevity.
What does this mean? One possible conclusion is obvious and tempting, even if it is a bit of a leap. CNN was happy to publish it: “Jonathan, the 194-year-old turtle, could help humans live longer.” Is this true? I mean, potentially. The researchers, like many before them, want to use Jonathan’s genes to unlock anti-aging technology for our own species. As study author Stephen Clark said, “Our goal is to take this evolving knowledge and immediately translate it into practical, affordable treatments for everyday people.” Clark is the founder of the nonprofit Kallel, whose website features an animation of a giant Aldabra tortoise, presumably Jonathan, being kidnapped and transformed into a strand of DNA, as well as AI art of Jonathan trapped in an hourglass.
Perhaps I’m being a spoilsport because of my prejudices against the human fixation on longevity and the insanity it often breeds. Who doesn’t want to live longer? I would definitely like to do it. Of course, scientists also conduct this research on humans; This paper studying the genome of a 117-year-old Spanish woman also found that she had exceptionally efficient mitochondria compared to other women her age. But the new article is exciting and revealing because it focuses on Jonathan as a turtle in a class of his own. His anti-aging “secrets” don’t need to apply to us to make headlines. For now, the only way to reach almost two centuries is to be a giant tortoise. This is an advantage that Jonathan will always have over us.
Gn world
