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Lifespan of humans

  1. Mar 16, 2010 #1
    dear readers,
    this has puzzled me for years.

    why do females tend to have a longer lifespan than males?

    i would much appreciate your answers
    Last edited: Mar 16, 2010
  2. jcsd
  3. Mar 16, 2010 #2


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    Staff: Mentor

    You are not the only puzzled by the question.

    I recall reading about research done somewhere in Scandinavia. Research was based on analysis of old records, going back to 19th or even 18th century. It turned out that families where there was Grandmother present were having on average more children surviving to adulthood. Could be that's evolutionary then - longer living woman have more chances or passing their genes to next generations.

    Scandinavia was a perfect place for research as many other factors were filtered out, but don't ask me about details. I believe this is a published work, should be possible to google.
  4. Mar 16, 2010 #3
  5. Mar 16, 2010 #4
    Females are genetically less crazy than males. They are significantly less likely to be killed in homicides, accidents and suicides. All else equal, an average male is almost 3 times more likely to die between ages of 15 and 30 than an average female. (And that's in our modern, relatively peaceful society. You can imagine what the ratio was like 100 or 200 years ago.) Males are more likely to abuse psychoactive substances, etc. Males are more likely to be exposed to continuous high levels of stress, and that is known to result in higher cardiovascular mortality later in life.
  6. Mar 16, 2010 #5
    So what you're saying its not a genetic difference rather than social?
  7. Mar 16, 2010 #6
    The reason why males and females behave differently may very well be genetic.
  8. Mar 16, 2010 #7
    Hamster: "Females are genetically less crazy than males" hehehe ...
    Another point: Women smoke significant less than men.
    Male exemplars of our species have a higher mortality than females during their whole lifespan, even when unborn.
    As compensation the production of males is around 5% higher than females.
  9. Mar 16, 2010 #8
    Its interesting, why human females live almost twice as long, as they are able to give birth. Obviously the grandmothers are good for something. Probably their increased knowledge and higher experience helps the grand-children to survive.
  10. Mar 16, 2010 #9


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    Staff: Mentor

    Something like that. From what I remember presence of Grandfathers didn't guarantee higher number of children surviving, so it was not just a matter of additional workforce present.
  11. Mar 16, 2010 #10
    I read or heard a long time ago that females have a stronger immune system than males.i dont know how much difference this would make or even if this is true though.
  12. Mar 16, 2010 #11
  13. Mar 17, 2010 #12
    I'm not sure if immune system is all that relevant any more. People rarely die from causes that can be prevented by strong immune system. Top 5 causes of death in the United States, percentages of total, and male-to-female ratios:

    1. Heart diseases: 26%, 1.5
    2. Cancer: 23%, 1.4
    3. Stroke: 6%, 1.0
    4. Chronic lower respiratory diseases: 5%, 1.3
    5. Accidents: 5%, 2.2

    Stroke is an equal-opportunity killer. 80% to 90% of "Chronic lower respiratory diseases" are due to smoking, and 1.3 male-to-female death ratio nicely reflects historical prevalence of smoking in the country.

    In cancers, the pattern is also quite clear: the one biggest killer is lung cancer, caused by smoking, and the death ratio is again 1.3. There are huge differences in death rates due to cancer of mouth (2.1), esophagus (3.6), and liver (1.9), all of which are usually caused by chronic excessive drinking. On the other hand, there are no significant differences between sexes in pancreatic and colon cancer (both often caused by excessive consumption of meat, particularly processed meat). The difference, of course, is that dangers of smoking and drinking have been known for a long time, and dangers of processed meat are still not fully part of public conscience. So, females are not significantly more resistant to cancers when exposed to carcinogens, but they are more capable of avoiding known sources of danger.

    The 1.5 ratio in heart diseases is a whole separate issue.
    Last edited: Mar 17, 2010
  14. Mar 20, 2010 #13
    Read Rick Lane books on evolution and life............its leaky mitochondria. That is the answer. His book is an amazing amalgamation of 5 disciplines. And all based on real science with references.
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