Why Do Women Live Longer than Men?

Blogger Dennis Mangan has proposed a somewhat-convoluted theory for why females live longer than males. He thinks it has to do with ancient polygamy.

One way to test this: Comparing sex-based differences in life-expectancy in U.S. blacks vs. U.S. whites. Black-African societies practiced polygamy, whereas Northern-Europeans never have. So, if Mangan’s theory is true, black-females should live longer relative to black-males than white-females live relative to white-males.

That may sound confusing. It should make more sense in table form.
I used CDC data to make the following table:

Life Expectancy by Race, Sex, and Age of Person. (Click to Expand).

This seems to vindicate Mangan’s theory. Doesn’t it?

Comments and Observations:
1.) Men Die Young More Often. The “pop” explanation for why women live longer: Men are killed far more often during their prime years, in accidents of all kinds, in homicides, suicides, and so on… and that they tend to have unhealthier habits (drinking, smoking). All valid points. But the beautiful thing about the CDC data is that we can look at life-expectancies for any particular age-cohort. So, if we only count persons currently 70-years-old, that would “factor-out” higher young-male mortality. Not many septegenarians are gunned down in drive-by-shootings or die in workplace accidents. The remaining length of life for people who have already survived to 60 or 70 is probably mostly-genetic. Isn’t it?

2.) True Difference Even Greater. Two things potentially mask the true sexual-dimorphisms here: a.) The black-American genepool is 20%-European: This would reduce any “native genetic sexual dimorphism” in longevity in blacks — the “pure black” dimorphism would likely be greater (presuming Northern-European genetics to be closer to 1:1 in male:female natural life-expectancies). b.) The white genepool is not 100%-Northern-European, but contains some amount of extra-European elements (which may have polygamist backgrounds). This would boost the “sexual dimorphism” in longevity for “whites”, to some extent. Despite these two things, greater sexual-dimorphism in blacks is still evident.

3.) “I Don’t Need to Go to the Doctor.” Commenter Sabril at Mangan’s blog suggests that males are more stubborn and refuse to go to the doctor more often than women. (Hence die younger). This may be so, but unless one further proposes that black-males are far more stubborn than white-males, there remains a greater sexual-dimorphism in life-expectancy among blacks.

.
Questions
1.) What could explain the longevity advantage black-females have (relatively) over white-females besides differing in-born genetic proclivities towards sexual-dimorphism in this way?
2.) What could explain how this genetic difference (if that is what it is) came about?

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12 Responses to Why Do Women Live Longer than Men?

  1. Statsaholic says:

    Black-African societies practiced polygamy, whereas Northern-Europeans never have.

    Hail,

    Where are you getting that?

    I could understand saying that polygamy was rarer in Northern than Southern Europe, on account of the climate in a lot of the north making the upkeep of multiple women and their children difficult.

    But to say that there was never polygamy in Northern Europe doesn’t make sense to me.

    The historic record in the northern parts of Europe doesn’t go back as far as it does in some parts of the southern parts of Europe.

    So even if the record of polygamy in ancient Southern Europe (found in Homer) has no corresponding account for ancient Northern Europe, this doesn’t really mean anything.

    Even more importantly, there’s strong evidence from historical times that polygamy was practiced to some extent in the north of Europe.

    “For every man has two or three or more women at the same time, according to the extent of his power; the rich and the rulers have more than they can count.”

    -Adam von Bremen, History of the Archbishops of Hamburg-Bremen

    This quote from Adam von Bremen is probably an exaggeration, but the fact remains that if polygamy and/or concubinage weren’t practiced to some extent by the Vikings, he never would’ve said it.

    Also, there’s very strong genetic and historical evidence that polygamy and/or concubinage were practiced in Ireland:

    “Gaelic society placed great emphasis on family relationships organized around a strongly patrilineal system (derbhfine) in which land and title could be handed down to successors chosen from within a kin group of male-lineage relatives. This wider inheritance cohort resulted in a decreased likelihood of dissociation of lineage from power (O’Croinin 1995). Also, whereas medieval Ireland was Christian, earlier marriage customs persisted and allowed divorce and concubinage. One feature of these customs was that illegitimate sons were claimed and had rights protected by law (Jaski 2000). As in other polygynous societies, the siring of offspring was related to power and prestige (Betzig 1995). For example, Lord Turlough O’Donnell (d. 1423) had 18 sons with 10 different women and counted 59 grandsons in the male line (Connolly 2002).”

    -‘A Y-Chromosome Signature of Hegemony in Gaelic Ireland’

    http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1380239/

    Please note that polygamy and concubinage have the same genetic effect.

    • Hail says:

      “Northern-Europeans have never had polygamy” may be an imprecise wording, granted. “They have never had the tradition of polygamy, except [insert exceptions here]” would be more precise, granted.

      The point is this: the white-American population descends much less from people selected for by polygamy than do black-Africans. This is inevitable.

      Therefore, that sexual-dimorphism in longevity is greater among blacks may be evidence for the longevity-gap’s connection to polygamy.

    • Hail says:

      polygamy and concubinage have the same genetic effect.

      Concubinage would imply a modern setting, so I don’t know.

      Remember, it’s not “the act of one man having children with multiple women”, it is the type of man selected for when such a thing is a social institution. In prehistoric times, the selection pressures involved would be somewhat different than today, surely.

  2. Statsaholic says:

    Black-African societies practiced polygamy, whereas Northern-Europeans never have.

    Also there’s the issue that Joseph Smith was a Northern European.

    http://www.mormontimes.com/article/10197/DNA-shows-Joseph-Smith-was-Irish

    He certainly practiced polygamy!

    • Hail says:

      Well, Mormonism was so hated in its early days because the early Mormons preached polygamy. This would qualify as one of those “exceptions that prove the rule”!

      Anyway, this is not a post about “Can you find instances of Northern-Europeans practicing polygamy?” It is clear that the selection pressure exerted by polygamy on the white-American stock over history is comparatively a lot lower than that exerted on the Black-African stock.

  3. Statsaholic says:

    The white genepool is not 100%-Northern-European, but contains some amount of extra-European elements (which may have polygamist backgrounds).

    The white genepool certainly includes people of Southern European ancestry, and about 3,200 years ago at least, polygamy and/or concubinage was being practiced in some parts of Southern Europe.

    The white genepool also includes people of Mormon ancestry, and some of their ancestors clearly practiced polygamy quite recently.

    The white genepool also includes some people of Eastern European ancestry, and I don’t know what was going on there with polygamy or the lack thereof before it was Christianized.

    So even if you’re right that polygamy was never practiced in Northern Europe, and I think there’s very strong evidence that you aren’t right, there’d still be a significant number of European-Americans with polygamous European ancestors.

    • Hail says:

      Statsaholic,
      You have pointed out that Europe has had some polygamy in its past, which may explain why white-females’ longevity is a little longer than white-males’, if Dennis Mangan’s theory is correct. (I don’t know if it is or not, I just looked at the numbers. I expected there to be no racial difference in female-longevity-advantage, after accounting for higher black-male mortality in younger years. I was wrong.)

      So even if you’re right that polygamy was never practiced in Northern Europe

      It is simply not a question of “All or nothing”. It is a question of selection pressures. What share of surviving children in the history of Europe were born to polygamist unions? What share were born to monogamous unions? Black-Africa will beat any part of Europe in share born to polygamist unions, far and away.

      Why does this matter? Because in a polygamist setting (in prehistoric times, anyway), there would be selection pressure against male longevity. According to Mangan. (I admit that I barely understand the mechanism behind such a thing). I also don’t know if such a selection pressure would still apply in modern polygamy, which tends to be more wealth-based than brute-strength based.

  4. Hail says:

    Here’s something interesting, thanks to Statsaholic for inspiring me to look this up:

    Life Expectancy among Mormons in Utah, 1994-1998.
    For those alive at age 80, the remaining years of life expected were 8.2 for LDS males, 10.3 for LDS females. [Link]

    For 60-year-olds, it is 25.0 vs. 21.1.

    What I called above the “f/m ratio” (see here):
    Mormons aged 60: 1.185
    Mormons aged 80: 1.256

    Both are higher than the national white ratios in 2000 and 2004. In the Mormons-aged-80 case, it is higher than the black ratio!

    Warning: The data is from a few years earlier and “f/m ratios” are declining over time for all age-race combinations. So there might be no story here. (Using data from multiple sources can show things that “just aren’t so”).

    It could also be an artifact of Mormons simply living longer: The older the current-age, the higher the ratio in whites. (See table).

    What is behind Mormon longevity, I wonder? A Mormon woman age-80 could expect to live past 90… and that was 15 years ago.

    Note that in Mangan’s “polygamy” theory, there is no mechanism for making the women live longer, it is all about making the men die earlier. The more common theory in science is that there is a biological basis for women to live longer.

  5. Fat Man says:

    Clearly you haven’t been married for 30+ years to the same woman. Every old married guy knows the answer to this question. It is because we want to die!

  6. Pingback: Primogeniture and Fertility | Hail To You

  7. Parker says:

    Some years ago I came across a book, and then several more, that stated prior to 1900, barring war and accidents owing to bravado, men lived longer than women. The basis for this point was that enormous numbers of women who died in childbirth. Not until birth procedures began reducing death rates, did their life spans of women advance ahead of men. This trend continued into the 1980s.

    It would stand to reason that because women died in such numbers at child birth, nature’s great equalizer would be the cautious nature of the lives they led, as well as a stronger immune system. I think human biodiversity scholars should take a closer look at this birth/death factor, before determining polygamy or any other cause(s) explains the discrepancy in life spans.

    As noted by a letter writer, the life expectancy span between men and women has been narrowing over recent years. What might be the cause of this? Men acting more like women in that they are accepting fewer challenges, and spending a greater part of their lives in waiting rooms?

    C

  8. Greg Marlow says:

    The mother’s body has evolved to support two lives – hers and her infants (both as developing fetus and nursing child). She must have an extra capacity to absorb nutrients to pass them to her child. As both sexes age they slowly loose their nutrient absorption capacity but the female has more to start with, so she has more to sustain her as she ages.

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