Older men who shack up with much younger women keep the grim reaper at bay for the human population and extend our species' lifespan, new research claims.
More interesting, when old men father children, their genes seem to increase the lifespan of both sexes over evolutionary time.
How it works:
Women often lose their reproductive capacity around age 50, but if men can still reproduce into their 70s, Darwin would say it's advantageous for males to live longer lives providing they can hook up with a woman capable of reproducing. Natural selection should favor longevity-boosting genes, which would get passed down from fathers to both sons and daughters. So women would benefit as well in future generations, the scientists say.
Result: Over time, the older-guy-with-younger-gal lifestyle would lift the lifespan ceiling for both men and women in the next generations and so on.
"By increasing the survival of men you have a spillover effect on women because men pass their genes to children of both sexes," said study team member Cedric Puleston, a doctoral candidate at Stanford University.
But why do men choose younger mates and females prefer older men?
"There is a lot of evidence from evolutionary psychology that men are seeking younger women and women are seeking older men," said anthropologist Martin Fieder of the University of Vienna, who was not involved in the current study.
Cases in point: At the age of 26, Anna Nicole Smith married 89-year-old Jeremiah Howard Marshall II. And in 1995, actor Tony Randall, then 75, married and had two kids with Heather Harlan, who was 24 at the time. Last month, 90-year-old Nanu Ram Jogi from India reportedly became the world's oldest father when he announced his 21st child.
Evolutionary psychologists argue that older men have more resources to protect and care for the family, while younger, more fertile women give their male partners better means of passing along genes.
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