Old men chasing young women: A good thing


September 13, 2007
Blog Entry, Health, Life & Non-humans

It turns out that older men chasing younger women contributes to human longevity and the survival of the species, according to new findings by researchers at Stanford and the University of California-Santa Barbara.

Evolutionary theory says that individuals should die of old age when their reproductive lives are complete, generally by age 55 in humans, according to demographer Cedric Puleston, a doctoral candidate in biological sciences at Stanford. But the fatherhood of a small number of older men is enough to postpone the date with death because natural selection fights life-shortening mutations until the species is finished reproducing.

“Rod Stewart and David Letterman having babies in their 50s and 60s provide no benefit for their personal survival, but the pattern [of reproducing at a later age] has an effect on the population as a whole,” Puleston said. “It’s advantageous to the species if these people stick around. By increasing the survival of men you have a spillover effect on women because men pass their genes to children of both sexes.”

“Why Men Matter: Mating Patterns Drive Evolution of Human Lifespan,” was published Aug. 29 in the online journal Public Library of Science ONE. Shripad Tuljapurkar, the Morrison Professor of Population Studies at Stanford; Puleston; and Michael Gurven, an assistant professor of anthropology at UCSB, co-authored the study in an effort to understand why humans don’t die when female reproduction ends.

Human ability to scale the so-called “wall of death”—surviving beyond the reproductive years—has been a center of scientific controversy for more than 50 years, Puleston said. “The central question is: Why should a species that stops reproducing by some age stick around afterward?” he said. “Evolutionary theory predicts that, over time, harmful mutations that decrease survival will arise in the population and will remain invisible to natural selection after reproduction ends.” However, in hunter-gatherer societies, which likely represent early human demographic conditions and mating patterns, one-third of people live beyond 55 years, past the reproductive lifespan for women. Furthermore, life expectancy in today’s industrialized countries is 75 to 85 years, with mortality increasing gradually, not abruptly, following female menopause.

Grandmother hypothesis

In 1966, William Hamilton, a British evolutionary biologist, worked out the mathematics describing the “wall of death.” Since then, the most popular explanation for why humans don’t die by age 55 has been termed the “grandmother hypothesis,” which suggests that women enhance the survival of their children and grandchildren by living long enough to care for them and “increasing the success of their genes,” Puleston said. However, Hamilton’s work has been difficult to express as a mathematical and genetic argument explaining why people live into old age.

Unlike previous research on human reproduction, this study—for the first time—includes data on males, a tweak that allowed the researchers to begin answering the “wall of death” question by matching it to human mortality patterns. According to Puleston, earlier studies looked only at women, because scientists can reproduce good datasets for humans entirely based on information related to female fertility and survival rates.

“Men’s fertility is contingent on women’s fertility—you have to figure out how they match up. We care about reproduction because that is a currency by which force of selection is counted. If we have not accounted for the entire pattern of reproduction, we may be missing something that’s important to evolution.”

Men and longevity

In the paper, the researchers analyzed “a general two-sex model to show that selection favors survival for as long as men reproduce.” The scientists presented a “range of data showing that males much older than 50 years have substantial realized fertility through matings with younger females, a pattern that was likely typical among early humans.” As a result, Puleston said, older male fertility helps to select against damaging cell mutations in humans who have passed the age of female menopause, consequently eliminating the “wall of death.”

“Our analysis shows that old-age male fertility allows evolution to breach Hamilton’s wall of death and predicts a gradual rise in mortality after the age of female menopause without relying on ‘grandmother’ effects or economic optimality,” the researchers say in the paper.

The scientists compiled longevity and fertility data from two hunter-gatherer groups, the Dobe !Kung of the Kalahari and the Ache of Paraguay, one of the most isolated populations in the world. They also looked at the forager-farmer Yanomamo of Brazil and Venezuela, and the Tsimane, an indigenous group in Bolivia. “They’re living a lifestyle that our ancestors lived and their fertility patterns are probably most consistent with our ancestors,” Puleston said about the four groups. The study also looked at several farming villages in Gambia and, for comparison, a group of modern Canadians.

In the less developed, traditional societies, males were as much as 5-to-15 years older than their female partners. In the United States and Europe, the age spread was about two years. “It’s a universal pattern that in typical marriages men are older than women,” Puleston said. “The age gaps vary by culture, but in every group we looked at men start [being reproductive] later. At the end of reproduction, male fertility rates taper off gradually, as opposed to the fairly sharp decline in female fertility by menopause.”

Despite small differences based on marriage traditions, all women and most men in the six groups stopped having children by their 50s, the researchers found. But some men, particularly high-status males, continued to reproduce into their 70s. The paper noted that the age gap is most pronounced in societies that favor polygyny, where a man takes several wives, and in gerontocracies, where older men monopolize access to reproductive women. The authors also cite genetic and anthropological evidence that early humans were probably polygynous as well.

Older male fertility also exists in societies supporting serial monogamy, because men are more likely to remarry than women. “For these reasons, we argue that realized male fertility was substantial at ages well past female menopause for much of human history and the result is reflected in the mortality patterns of modern populations,” the authors say. “We conclude that deleterious mutations acting after the age of female menopause are selected against … solely as a result of the matings between older males and younger females.”

According to Puleston, the “grandmother hypothesis” may be true, but the real pattern of male fertility extends beyond this explanation. “The key question is: Does the population have a greater growth rate if men are reproducing at a later age? The answer is ‘yes.’ The age of last reproduction gets pushed into the 60s and 70s if you add men to the analysis. Hamilton’s approach was right, but in a species where males and females have different reproductive patterns, you need a two-sex model. You can’t correctly estimate the force of selection if you leave men out of the picture. As a man myself, it’s gratifying to know that men do matter.”

Grants from the U.S. National Institute on Aging supported this study.


1,798 Responses to Old men chasing young women: A good thing

  1. Nat February 12, 2014 at 6:41 pm #

    I’ve got a 60+ bitch at home that’s all saggy and floppy, sort of the beached whale look.
    I’m saggy also but I still appreciate a young lady who is built and beautiful. I also tell her that she is beautiful.

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  3. EhiozeChris October 8, 2013 at 8:25 am #

    That’s not absolutely true. Spem count is less conceivable than ovulation for many young men. A lot of young women find it harder to conceive these days too. I’m male, my girlfriend is 30 years older than me, and we have great love life. I have no children exept hers. She had one after the other until there was over eight of them. Her lesson changed my life, not natural selection. Only children are subject to “primitivism” , as I call this subject. You wont see me start another family of my own sometime in the near future. Look what they do to their parents when they get old. I hope you can see how our roles get reversed occasionally? The only thing that’s leading our growth is the learning of love and care for the family. That doesn’t mean men should go around rush breeding before they die. The bigger picture is, where most women have respect for our bodies, most men degrade them. Sperm is a rush until we reach 41. A strong man is able to hold back from sexual desire. Weak men show off until they are bad examples of fatherhood and natural selection. Strong men always come out on top in the end. The older the better the alpha male.

  4. semsem March 14, 2013 at 1:26 am #

    How to tell a gay when a girl is 100% not interested?

    Listen men, women are giving signals that they don’t want any thing to do with either because you are too old, ugly, too short, poor, rich, bold, too tall. There is a reason why woman is not interested in you and she is giving signals that she doesn’t want to you, so follwing her around, using triks every thing to get to her is not helping. So you better leave her alone. She knows what she want. She doesn’t want to spend any time on you, so you better not to waste your time specially if you are older than 40 or 50, you don’t have a time to spend your time on someone doesn’t want to you.

    Why would an attractive, sexy, beautiful, smart, intellegent, emotional stable girl will want to be with you. What makes you to be better than the other men who wants her make you differnt. you should know you don’t have any chance.

    The attractive girl doesn’t want you because you are rich even if you are rich. the attractive girl doesn’t want to you if you are poor either. which is there is more to it than what you have what you don’t have, so you should know when she say, she has a h usband, boyfriend, doesn’t call you back ot text you back or stop emailing you back also ignoring you any time you try to talk to her because you are going after where she goes. Those reasons what she is doing must be enough to make you understand that she is not interested in you but you must to be dump that you don’t understand what she is trying to tell you but she doesn’t want to be rude.

    So just give up there no any reason for her that will make her to have any feeling for you. There is many reasong she doesn’t like about you but she can’t say it to your face so get over it .

    going every where where she goes and pretending is not making you any favor. you should know she doesn’t want you because she is not the one following you around. She is not the one calling or texting you. That makes you just damp ass who do not understand about people.

    Sorry, but that is the true, so live your life and don’t hope for that peoutiful attractive gire to be your girefriend or a wife because she she will not. She knows what she want she doesn’t need any dumb ass people following her around specially when she is not even interested.

    I am sure there are other girls every where they want a man like you. You can check to where she works or school, you will find there. They are very nice girls there they will be happy to be with you and your money. Just spend time on these ladies, they will be happy to be with you., don’t spend your time and your energy on some one who not interested in you……………………

    There is a reason why she is not answering or texting even not even using her phone and having a private phone number and she only used.

    by now you should understand. There is no way that attractive women will sleep with you specially if she was with someone attractive handsome man than you. some times you should figure out the girls previous relashionship she had.

    SORRY AND have FUN with time you have left and enjoy your life don’t wast it.
    I am SURE you will find one that will much with you.
    I am sure after you read this you will understand what to do next so you don’t have to follow some one is not interested in you.

    In case Is I don’t comeback to this post, I have to say:

    GOOD BYE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

  5. Seriously? January 29, 2013 at 1:23 am #

    The general guide is no younger than half his age plus 7.

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  10. John July 21, 2012 at 11:46 pm #

    Women 35-year old (+) present increased risk for Downs Syndrome primarily, and men 40-year old (+) present risk for autism in offspring… statistically.

    And, as a man, I agree with your comment on empowerment… as when I hit 40, total loss of control happened in the home. If I tried to hold on tight to it, the more I lost it… and then it was too late. I separated from my wife of nearly 20 years last week. Were you to observe, it was clear who was in control, and it is quite uncomfortable to be in that spot… so, when I was asked to leave… I said “OK.”

    If you have kids, stop while you are ahead… what if you have some raging autistic child who screams and moans all the time – you would kick yourself for it. Good luck!

  11. Tyler Eugene Nelson June 28, 2012 at 5:22 am #

    Make sure they’re not too young. You’ll have to get married. Oh, and don’t be creeper either

  12. jason June 27, 2012 at 4:25 am #

    there should be a difference of at least 10 to 15 years between men and women..cause women gets old very fast while men are men..they never get old… so in my opinion = Old men chasing young women: A good thing (yea it is totally)

  13. Jon May 13, 2012 at 2:25 am #

    I thought it was only lower sperm count, not the condition of the cells themselves. It’s not las if older men produce mutants you know. I am 41 and would like to have more children, I am in the financial position to provide for them.

    I understand my role in evolution as a protector and provider, and I greatly appreciate womens’ roles as childbearers, mothers, pillars of emotional support for both men and children. I don’t think women should feel like this is demeaning. You should know that being a man isn’t as empowering in someways as you might think. A man’s life can be very demanding, and women in fact have much control over men; more than you probably realize. I have often felt controlled by women and their sexuality, but I am not bitter about it. In the right environment men and women can be mutual benefactors for each other.

  14. Pension Release March 20, 2012 at 11:31 am #

    Thank you for this very helpful article. I have found it quite useful.

  15. adriandrummond March 14, 2012 at 7:58 am #

    You decided nothing., You were born a lesbian.

  16. Danno March 14, 2012 at 6:41 am #

    Doubt you would call it misandry if the research mentioned in the article ended up with an opposite result.

  17. Danno March 14, 2012 at 6:37 am #

    So, tell me my dear, is biology with all its bio-chemical processes misogynistic?

  18. Danno March 14, 2012 at 6:34 am #

    But, alas the young men want young women as well. So, no harems stocked with young men for older women. um..sorry.

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