The longtime record-holder for the oldest person who ever lived might have been a fraud, according to a new study.
French woman Jeanne Calment died in 1997 at the age of 122 years and 164 days, according to Guinness World Records.
But new evidence suggests the woman who died in 1997 might actually have been her daughter Yvonne, who "acquired her mother's identity after her death in order to avoid paying inheritance tax".
Nikolay Zak of the Moscow Center for Continuous Mathematical Education and gerontologist Valery Novoselov argue in a new paper there are "multiple contradictions in her interviews, biographies, photos, and documents".
They say Jeanne actually died in 1934 of a lung infection at the age of 59 - but her death was reported as Yvonne's, who was only 42 at the time.
The evidence includes an identity card from the 1930s which gets Jeanne's height and hair colour wrong; that Yvonne's husband never remarried and instead raised her son alongside 'Jeanne' - who was actually Yvonne; and that most of Jeanne's papers were destroyed rather than archived after she died, suggesting the family had something to hide.
Yvonne was only 99 when she died in 1997, posing as Jeanne, according to the pair.
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"The phenomenon of Jeanne Calment could be used as an example of the vulnerability of seemingly well-established facts," they write.
But the gerontologist who validated Jeanne's claim in the 1990s dismissed the theory as "preposterous".
"Do you have any idea how many people would have needed to lie?" Jean Marine told French newspaper Le Parisien.
"All of this is incredibly shaky and rests on nothing."
The paper has not been peer-reviewed, adding to the scepticism.
It's been suggested the only way to know for sure would be to exhume the bodies.
Jeanne's record far outstrips the second-placed longevity holder - 119-year-old US woman Sarah Knauss. All of the 10 longest-living humans so far have been women, three of them from Japan.