Scientists have discovered the secret to eternal youth: Be born a turtle.
A study published on Thursday in the journal Science revealed scant evidence of aging among certain cold-blooded species, challenging a theory of evolution, which holds that senescence, or gradual physical deterioration over time, is an inescapable fate.
Although there have been eye-catching individual reports — such as that of Jonathan the Seychelles tortoise who turns 190 this year — these were considered anecdotal, and the issue had not been studied systematically, said Pennsylvania State University wildlife ecologist David Miller, a senior author of one of the papers.
Photo: EPA-EFE
Researchers have “done a lot more comparative, really comprehensive work with birds and animals in the wild,” he said, “but a lot of what we knew about amphibians and reptiles were from a species here, a species there.”
For their paper, Miller and colleagues collected data from long-term field studies comprising 107 populations of 77 species in the wild, including turtles, amphibians, snakes, crocodilians and tortoises.
These all used a technique called “mark-recapture,” in which a certain number of individuals are caught and tagged, then researchers follow them over the years to see if they find them again, deriving mortality estimates based on probabilities.
They also collected data on how many years the animals lived after achieving sexual maturity, and used statistical methods to produce aging rates, as well as longevity — the age at which 95 percent of the population is dead.
“We found examples of negligible aging,” said biologist and lead investigator Beth Reinke of Northeastern Illinois University.
Although they had expected this to be true of turtles, it was also found in one species of each of the cold-blooded groups, including in frogs and toads and crocodilians.
“Negligible aging or senescence does not mean that they’re immortal,” she said, adding that it means there is a chance of dying, but it does not increase with age.
By contrast, among adult females in the US, the risk of dying in a year is about one in 2,500 at age 10, versus one in 24 at age 80.
The study was funded by the US National Institutes of Health, which is interested in learning more about aging in ectotherms, or cold-blooded species, and applying them to humans, who are warm-blooded.
Scientists have long held ectotherms — because they require external temperatures to regulate their body temperatures and therefore have lower metabolisms — age more slowly than endotherms, which internally generate their own heat and have higher metabolisms.
This relationship holds true within mammals. For example mice have a far higher metabolic rate than humans and much shorter life expectancy.
Surprisingly, the new study found metabolic rate was not the major driver it was previously thought.
“Though there were ectotherms that age slower and live longer than endotherms, there were also ectotherms that age faster and live shorter lives,” after controlling for factors such as body size, the study said.
The study also threw up intriguing clues that could provide avenues for future research. For example, when the team looked directly at average temperatures of a species, as opposed to metabolic rate, they found that warmer reptiles age faster, while the opposite was true of amphibians.
One theory that did prove true is that those animals with protective physical traits, such as turtle shells, or chemical traits such as the toxins certain frogs and salamanders can emit, lived longer and aged slower compared to those without.
“A shell is important for aging and what it does is it makes a turtle really hard to eat,” Miller said.
“What that does is it allows animals to live longer and for evolution to work to reduce aging so that if they do avoid getting eaten, they still function well,” he added.
Four people jailed in the landmark Hong Kong national security trial of "47 democrats" accused of conspiracy to commit subversion were freed today after more than four years behind bars, the second group to be released in a month. Among those freed was long-time political and LGBTQ activist Jimmy Sham (岑子杰), who also led one of Hong Kong’s largest pro-democracy groups, the Civil Human Rights Front, which disbanded in 2021. "Let me spend some time with my family," Sham said after arriving at his home in the Kowloon district of Jordan. "I don’t know how to plan ahead because, to me, it feels
The collapse of the Swiss Birch glacier serves as a chilling warning of the escalating dangers faced by communities worldwide living under the shadow of fragile ice, particularly in Asia, experts said. Footage of the collapse on Wednesday showed a huge cloud of ice and rubble hurtling down the mountainside into the hamlet of Blatten. Swiss Development Cooperation disaster risk reduction adviser Ali Neumann said that while the role of climate change in the case of Blatten “still needs to be investigated,” the wider impacts were clear on the cryosphere — the part of the world covered by frozen water. “Climate change and
Poland is set to hold a presidential runoff election today between two candidates offering starkly different visions for the country’s future. The winner would succeed Polish President Andrzej Duda, a conservative who is finishing his second and final term. The outcome would determine whether Poland embraces a nationalist populist trajectory or pivots more fully toward liberal, pro-European policies. An exit poll by Ipsos would be released when polls close today at 9pm local time, with a margin of error of plus or minus 2 percentage points. Final results are expected tomorrow. Whoever wins can be expected to either help or hinder the
DENIAL: Musk said that the ‘New York Times was lying their ass off,’ after it reported he used so much drugs that he developed bladder problems Elon Musk on Saturday denied a report that he used ketamine and other drugs extensively last year on the US presidential campaign trail. The New York Times on Friday reported that the billionaire adviser to US President Donald Trump used so much ketamine, a powerful anesthetic, that he developed bladder problems. The newspaper said the world’s richest person also took ecstasy and mushrooms, and traveled with a pill box last year, adding that it was not known whether Musk also took drugs while heading the so-called US Department of Government Efficiency (DOGE) after Trump took power in January. In a
RSS