Polygamy hurt 19th century Mormon wives' evolutionary fitness

Feb 22, 2011
This is an illustration from from "The Women of Mormonism or the Story of Polygamy as Told by the Victims Themselves," by Jennie Anderson Froiseth (1882). Credit: Courtesy of the IU Lilly Library

Polygamy practiced by some 19th century Mormon men had the curious effect of suppressing the overall offspring numbers of Mormon women in plural marriages, say scientists from Indiana University Bloomington and three other institutions in the March 2011 issue of Evolution and Human Behavior.

Simply put, the more sister-wives a Mormon woman had, the fewer children she was likely to produce.

"Although it's great in terms of number of children for successful males to have harems, the data show that for every new woman added to a male's household, the number each wife produced goes down by one child or so," said IU Bloomington Michael Wade, whose theoretical work guided the study. "This regression is known as a 'Bateman gradient,' named after the geneticist who first observed a similar phenomenon in fruit flies."

The paper's coauthors were Jeffrey Moorad (Duke University, Indiana University Ph.D. 2005), Daniel Promislow (University of Georgia), and Ken Smith (University of Utah).

The researchers' survey of birth, marriage and death records from the Utah Population Database covers nearly 186,000 Utah adults and their 630,000 children who lived or died between 1830 and 1894. This period marked an important transition for the nascent Mormon Church, as polygamy began to be phased out in deference to U.S. laws banning the practice but also via internal pressure from the Mormons themselves.

The scientists' study confirmed their expectation that a moratorium on Mormon polygamy would have the effect of decreasing the intensity of sexual selection among males and ultimately bringing the strength of reproductive selection on men closer to that acting on women. With fewer polygamous marriages, more males had access to wives, which led to a decrease in the variation in Mormon males' mating and reproductive success. The scientists estimate that ending polygamy reduced the strength of sexual selection on males by 58 percent.

"This study was very exciting for us, in large part because you just don't get to see the demographic effects of dramatically changing a mating system within a single population -- in any organism," Wade said. "It's an added bonus that this change from polygamy to monogamy just happened to involve people who kept such thorough records of the marriages, births and deaths at that time."

Wade, who specializes in the evolutionary biology of mating systems, says much of his work has elucidated and expanded on the ideas of Angus Bateman. Bateman, a prolific theorist, was unable to empirically test all his theories about mating and mating fitness before he died in 1996. Last year Wade and Northern Arizona University biologist Stephen Shuster co-wrote a retrospective on a classic paper Bateman wrote for the journal Heredity in 1948. Wade and Shuster extolled Bateman's vision, in particular the way in which Bateman thought sexual selection should be quantified. Bateman's critics thought his reductions of biology were too simplistic, yet Wade says Bateman's simple formulas are often dead-on.

This is a homestead of Joseph Smith, founder of the Mormon church. Credit: Church of Latter-Day Saints

"Bateman's ideas still are very much alive, the present study included," Wade said. "It was also his idea that selection could be stronger on males than on females, that what can be an advantage to males can be a disadvantage to females of the same species. And the advantage isn't just in having more mates. You may simply produce more offspring, than the average, if you're a male successful in reproductive competition against other males."

Which isn't to say systems of polygamy in humans or elsewhere in nature are necessarily good for all the males involved. Indeed, Wade says, polygamy is a bad thing for most males of a species.

"When the ratio of sexes is about equal, for every male that has three mates, there must be two males that have none," Wade said. "If a male has even more mates, then the disparity among male 'reproductive' haves and have-nots can become quite great."

So if polygamy (or the female equivalent, polyandry) is disadvantageous to most of the sequestered sex and most of the mate-sequestering sex, why should such systems survive?

"The complete answer is still forthcoming," Wade said. "One thing we know now, based on rigorous studies in many species, particularly the fruit fly, is that selection can be so strong on males that it can drag the entire species off of a naturally selected viability optimum."

Wade points to a familiar example.

"Take the peacock," Wade said. "Its tail is magnificent for attracting females and bad for attracting predators. It is believed that in some situations there is a "predator hard cap" on the fitness of sexual characteristics. But there's also research suggesting even the predator hard cap can be overpowered if on males is strong enough. That is, males trade high risks to their lives in order to gain large numbers of mates and thereby offspring."

Explore further: Fruit colours evolved to please picky birds, study says

More information: "Mating system change reduces the strength of sexual selection in an American frontier population of the 19th century," Evolution & Human Behavior, vol. 32, iss. 2, pp. 79-156 (March 2011)

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Moebius
4.2 / 5 (5) Feb 22, 2011
Polygamy practiced by some 19th century Mormon men had the curious effect of suppressing the overall offspring numbers of Mormon women in plural marriages


It says that like it's a bad thing.
trekgeek1
5 / 5 (3) Feb 22, 2011
Polygamy practiced by some 19th century Mormon men had the curious effect of suppressing the overall offspring numbers of Mormon women in plural marriages


It says that like it's a bad thing.


Zing
Sweetcheeks
1.8 / 5 (5) Feb 23, 2011
No need to bash religions. Mormons have a net good effect in the world.
JRDarby
4.3 / 5 (6) Feb 23, 2011
It depends on how you define good. And I'd like to point out that only around 20% of men in the church practiced polygamy. This number was influenced by the availability of resources so often it was only church leadership that was able to support multiple wives. This relationship between provision and polygamy is one that has existed in all cultures that have practiced polygamy: you can only have wives you can support. Pardon my anthropological digression.
jamesrm
1 / 5 (1) Feb 23, 2011
Momons are just kinda retro scientologists? ... right?

rgds
jms
Skeptic_Heretic
5 / 5 (5) Feb 23, 2011
No need to bash religions. Mormons have a net good effect in the world.

So do some murderous dictators. That doesn't make their actions or intents sacrosanct.
DJ311
5 / 5 (2) Feb 23, 2011
Perspective: I suspect more Muslim men have practiced polygamy in massively greater numbers over the years than Mormons....same goes for most tribal systems...
Article is profoundly pointless from an evolutionary sense as many animal species engage this way....
chasjones
not rated yet Feb 23, 2011
It would be interesting to sample the Y chromosone diversity among the male populations which have those 200 year old roots in the state. The genes of Ghengis Khan are found in a large portion of the people who today live in his prior domain. I wonder if Brigham Young or some other elder dominates in Utah. Don't LDS members go to great efforts to research genealogy to prove a relationship to him, much as Jews try to make a connection to David?
TheGhostofOtto1923
2.7 / 5 (14) Feb 23, 2011
No need to bash religions. Mormons have a net good effect in the world.
Yah. In related news, one of the worlds great religionist criminals photographed...
http
://www.dailymail.co.uk/news/article-1358654/The-worlds-biggest-family-Ziona-Chan-39-wives-94-children-33-grandchildren.html

"Coincidentally, Mr Chana is also head of a sect that allows members to take as many wives as he wants." If youll examine the pictures closely you may note a significant number of apparent cretins and imbeciles, including the one standing out front. A possible sign of unfortunate inbreeding? I could be wrong.

-Another tidbit: Osama bin Ladens father "sired a total of 54 children, by 22 wives. Mohammed never had more than four wives at a time - having divorced older wives and married new ones as needed to limit the number of current wives to four."

-Which is another approach.

Religions care NOTHING about the future.
trekgeek1
4.3 / 5 (6) Feb 23, 2011
Even the most gentle religions harms society because they foster the belief in supernatural and teach how to ignore scientific evidence and probability.
JRDarby
2.4 / 5 (7) Feb 23, 2011
Even the most gentle religions harms society because they foster the belief in supernatural and teach how to ignore scientific evidence and probability.


Okay, I realize this is Physorg, and I'm an atheist like most of you, but this anti-religionist sentiment has gone too far. The fact that religion has survived as long as it has illustrates that it serves a purpose (for some people). Unfit memes, like genes, do not last long. Not all religious people fit a mold. There are religions that do not promote authoritarian power structures, that promote selflessness for no reason other than it is "good," and not all religious people are nutbags. Having grown up in a fundamentalist Christian family in the South, my view of religion was poisoned by these people--but I've come to the more mature conclusion that though most religions historically have acted poorly (or worse), not all religions, especially these days, and not all religious people are that bad.
JRDarby
2.6 / 5 (5) Feb 23, 2011
And as to fostering belief in the supernatural and teaching to ignore scientific evidence and probability, that's more generalization and bullshit on the level of what I grew up in. Not all religions, gentle or not, foment these beliefs in their followers. Likewise, religious practice is not mutually exclusive with acceptance of the efficacy of the scientific method nor its fruits. Frankly I think it's hypocritical that you insinuate criticism of religious peoples' closed-mindedness while simultaneously closing yourself to the possibility of the supernatural (however you formulate your conception thereof). In short, I don't want to stir the pot any more than it has, but as atheists we can't wave our hands to group all religions and religious people in one category to dismiss them. Like most phenomena, religion is complex and can't be reduced to any one category or cause.
Ethelred
5 / 5 (1) Feb 24, 2011
Otto

Would you mind terribly not using sockpuppets? If it is reprehensible for Alizee then it is reprehensible for YOU. The only excuse for doing that is in a tit for tat situation.

Ethelred
Skeptic_Heretic
4.3 / 5 (6) Feb 24, 2011
Okay, I realize this is Physorg, and I'm an atheist like most of you, but this anti-religionist sentiment has gone too far. The fact that religion has survived as long as it has illustrates that it serves a purpose (for some people).
If an adult coworker turned to you and said he couldn't wait until Santa came to town for Christmas, and meant it, what would you do?

I'd point and laugh. Living in a fantasy world is risible, period.
JRDarby
3 / 5 (2) Feb 24, 2011
If an adult coworker turned to you and said he couldn't wait until Santa came to town for Christmas, and meant it, what would you do?

I'd point and laugh. Living in a fantasy world is risible, period.


But my point is that religion for all people isn't a literal "God made the earth in seven human days" phenomenon. I know several people (and I live in one of the most conservative towns in Texas of all places!) that call themselves Christians but take the Bible as a metaphor and its stories as symbols.

I completely agree that it is pitiable to see adults who should (and do in many cases) know better accepting myth as literal fact. That said, not all do, and pointing and laughing at them won't help those who do see where they're wrong. If we want to take the intellectual and moral high ground, we have the responsibility to act like the adults we purport to be.
JRDarby
3 / 5 (2) Feb 24, 2011
Furthermore, I have sympathy for these people because I used to be where they are. I grew up in a very restrictive environment and didn't start to see things differently until my mid-teens. I know first-hand what it's like to have everything and everyone around you in your closed and closed-minded community push you away from the truth that the religion you've grown up with is a myth and nothing more, nothing less. I realize I'm not representative of all people, and that many people have no rational excuse for believing what they do, but browbeating them won't solve anything.
JRDarby
3 / 5 (2) Feb 24, 2011
And speaking of rational, I think the problem with religion is largely that it appeals to a very primitive, non-rational part of the mind/brain. These people think their beliefs are rational, but what they really experience is the *feeling* of things being "right" because they are pressing the right mental buttons. In many cases, I find that these people have preconceived notions of reality (e.g. something is wrong with the world) and religions come along and provide an answer (you're a sinner and Jesus will save you).

In short, the problem with religion is laziness. Instead of thinking consciously and rationally, people think unconsciously and, understandably, irrationally--which isn't really thinking at all.

Where the hypocrisy comes in is that people who "believe in science" (I hate that phrase because it really doesn't mean anything, but you understand what I'm saying) are just as guilty just as often of this same mistake. We should look inwardly before criticizing others.
Skeptic_Heretic
3.7 / 5 (3) Feb 24, 2011
But my point is that religion for all people isn't a literal "God made the earth in seven human days" phenomenon. I know several people (and I live in one of the most conservative towns in Texas of all places!) that call themselves Christians but take the Bible as a metaphor and its stories as symbols.
Great, then they're 5% further than their ridiculous compatriots into the world fo rational thought.
I completely agree that it is pitiable to see adults who should (and do in many cases) know better accepting myth as literal fact. That said, not all do, and pointing and laughing at them won't help those who do see where they're wrong.
I don't care to show them where they are wrong. They are adults, they are capable and unwilling to determine this for themselves. Constant derision forces introspection. If we walk around, hand in hand, telling them it's ok to act like a moron, guess what they're going to do....

Sign up for a physorg account like kevinrtrs and spew nonsense
JRDarby
1 / 5 (1) Feb 24, 2011
I five-starred you, SH, because I agree that religion, especially fundamentalism in any form whatsoever, is laughable. But it's also painful to see the exact same sort of generalizing, exclusionary rhetoric and behavior I see in my family at home also occur here among people that I know are well-educated and of sound mind. My point in all this was never to stir the pot, nor to cast the religious as underdogs or martyrs, but to point out that we have to apply the same rigorous standards of conduct to ourselves as we do to others.
JRDarby
1 / 5 (1) Feb 24, 2011
I don't care to show them where they are wrong. They are adults, they are capable and unwilling to determine this for themselves. Constant derision forces introspection. If we walk around, hand in hand, telling them it's ok to act like a moron, guess what they're going to do....

Sign up for a physorg account like kevinrtrs and spew nonsense


I've followed your posting history off and on and respect you for your comments. That said, I think you're off your rocker if you think constant derision forces introspection. It doesn't. It pummels these people further and further into their cognitive ruts, forces them to band together to cling to their stupid ideas, and makes their beliefs STRONGER than they were before.

No one said we should tell them they're right: we shouldn't because they aren't. But your tack in this is all wrong and counterproductive. Do you *want* the Tea Party/Sarah Palin nutbags running this country? Consider the practical implications of what you're doing.
Skeptic_Heretic
3.7 / 5 (3) Feb 24, 2011
No one said we should tell them they're right: we shouldn't because they aren't. But your tack in this is all wrong and counterproductive.
How exactly are these nuts going to get elected when the majority of the electorate laughs in their face? Oh thats right, we don't. We let people get on stage and say "I don't believe in evolution, but I'm going to be your president." and NO ONE sees anything wrong with that. That's retarded reasoning. When spomeone says "I'm a person of faith" you respect them. I don't. Why? There's nothing to respect about someone who believes something despite the evidence.

Skeptic_Heretic
4 / 5 (4) Feb 24, 2011
JR, I agree that the standards must be the same, and they are. If I state "I have faith in (insert hypothesis X)" I expect to get both barrels and have on this very site, as expected. No one is free of scrutiny, only those who fail to recognize proper argument are the ones constantly subjected to it.
JRDarby
3 / 5 (2) Feb 24, 2011
Again, generalizations. I realize that GWB was president for eight years, but the majority (by popular vote) did not elect him. It's not the case that "NO ONE" sees anything wrong with a Creationist political leader: I certainly do! People speak up about it quite often, but national media outlets do not carry these stories. I do not at all respect someone simply because they believe in a big man in the sky who makes all the naughty things you did okay. I agree that there is nothing to respect about these people and, in fact, they are the opposite of respectable in that regard.

But, again, the fact that some (even most!) of the religious people here and elsewhere have silly beliefs does not mean that all of them do and if for no other reason than that we should be on guard against generalization, i.e. intellectual laziness, we should qualify our objections to religion and religious people. This is why the antireligious statements made here have come under my scrutiny.
JRDarby
3 / 5 (3) Feb 24, 2011
The problem, as I see it, is that we're letting our emotions get in the way of our reasoning--just like the religious people. We can't let our distaste for religion, and all the evil it has wrought, come between our commitment to intellectual honesty and sincerity. Sure, we're held to a higher standard than the religious people, and we should be--and even more we should follow that standard instead of casually dismissing all religions and all religious people in one wave of the hand.

I appreciate you discussing this with me, SH.
Skeptic_Heretic
3 / 5 (2) Feb 24, 2011
I agree that there is nothing to respect about these people and, in fact, they are the opposite of respectable in that regard.
Then why are you asking me to not ridicule them on site?

Faith is belief despite evidence, which is self delusion. You're effectively asking me to allow psychotics to have their little fantasy because it isn't hurting anyone (at the moment). Well that's false. It's hurting many people all over the world right now. There is no such thing as an innocent adherant when the policy they adhere to promotes horrors in the world. It isn't generalization, it is full disclosure.

I don't have an emotional feeling on the matter, I simply have my solid stance that self-delusion is dangerous, and I can demonstrate it easily. If you deem my stance to be dismissal of religion, you're half right. Then again, I could always challenge you to find one that is innocent of these very same horrors.
JRDarby
3 / 5 (2) Feb 25, 2011
I'm not asking you to allow psychotics their fantasy, as you put it, but to change your approach to dealing with the problem. I think the approach most people take is dictated by their emotional reaction to the issue. We're upset that they fight against evolution being taught in schools, that "people of faith" are somehow given free passes for wrongs they commit, and that if a belief is religious in nature it is somehow culturally immune to the inspection of reason. But, again, we can't let this come between us and the standards to which we must hold ourselves. You may say you have no emotional feeling on the matter but I think your posts (as well as others') demonstrate otherwise--and that's understandable, but again we mustn't let it get in the way of reasonable debate.
trekgeek1
5 / 5 (1) Feb 25, 2011
How exactly are these nuts going to get elected when the majority of the electorate laughs in their face? Oh thats right, we don't. We let people get on stage and say "I don't believe in evolution, but I'm going to be your president." and NO ONE sees anything wrong with that. That's retarded reasoning. When spomeone says "I'm a person of faith" you respect them. I don't. Why? There's nothing to respect about someone who believes something despite the evidence.



Did I hear some Sam Harris in there? I think I did.
Skeptic_Heretic
1 / 5 (1) Feb 26, 2011
But, again, we can't let this come between us and the standards to which we must hold ourselves. You may say you have no emotional feeling on the matter but I think your posts (as well as others') demonstrate otherwise--and that's understandable, but again we mustn't let it get in the way of reasonable debate.
It's not a reasonable debate when the rules aren't the same for us and them. I'm enforcing the standardized rules. If you can't show it, you don't know it, if you claim to know it and can't show it, you're a fraud and a liar and shall be treated as such.

Is that clear and objective enough for you?
TheGhostofOtto1923
2 / 5 (8) Feb 28, 2011
It depends on how you define good. And I'd like to point out that only around 20% of men in the church practiced polygamy.
These religions are typically designed to maximize growth as quickly as possible. Women in polygamous situations, according to the article, produce 1 or 2 fewer than the 15 or so they are required to.
This number was influenced by the availability of resources ...This relationship between provision and polygamy is one that has existed in all cultures that have practiced polygamy: you can only have wives you can support.
That is not true. Fundamentalists believe that GOD will provide for as many children as the faithful can produce. And when they begin to starve, preachers will remind them that it is the heathens who are at fault. This is a mechanism of aggression and conquest; their Purpose. With Mormons it was a way of populating a resource-rich area of the country with workers.
Ethelred
5 / 5 (1) Feb 28, 2011
Otto that is not well thought out. The Church of the Latter Day Saints was founded when there was a rather large number of women without men to marry due to the heavy losses during the Civil War which made polygamy a rather practical solution to what was a tragic problem for many women. And Smith took advantage of it.

When he first made that crap up while literally talking through his hat he did not promote polygamy. He did that later. I suspect it was because he had more women interested in HIM then when he was running his crystal viewing con. Instant harem, but as a church leader he couldn't just start living with them so he had to make it a Holy Thing. And with the surfeit of women over men, allowing polygamy would give his religion an advantage in gaining new members both male and female. I really don't think he was thinking about raising more children. His long term success probably surprised him.

Ethelred
TheGhostofOtto1923
2 / 5 (8) Feb 28, 2011
Even without these designer religions to maximize growth and aggression humans, like any other animal, will always tend to produce more offspring than can be expected to survive to maturity. The ratio of reproduction to attrition is adjusted through evolution and biological adaptation. Humans have managed to reduce natural attrition pressures far more quickly than their biology could compensate.

We are a runaway, tropical, invasive species in a temperate environment. We have tried to compensate culturally, but even cultural development cannot keep pace with our ability to outgrow resources. This has led to the inevitability of war, famine, and plague throughout history as natural or Artificial ways of preserving the species and all of it's most irreplaceable Products.
TheGhostofOtto1923
2 / 5 (8) Feb 28, 2011
Otto that is not well thought out. The Church of the Latter Day Saints was founded when there was a rather large number of women without men to marry due to the heavy losses during the Civil War which made polygamy a rather practical solution to what was a tragic problem for many women. And Smith took advantage of it.
No sir, it is you who are not out well-thinking. These women were an unused commodity, in a manner of speaking. The LDS church assembled it's flock, relocated itself to the target region, and developed it's lunatic credo and culture along the way. It's most significant result was, as I said, to populate an uninhabited region full of strategic resources as quickly as possible. You sound as if you believe that somebody couldn't have concocted this whole Campaign for this very Purpose? As if it hadn't been done innumerable times in the past? As if Moses hadn't described the Process in the Torah?

We are exceedingly easy to herd.
TheGhostofOtto1923
1.9 / 5 (8) Feb 28, 2011
When he first made that crap up while literally talking through his hat he did not promote polygamy. He did that later. I suspect it was because he had more women interested in HIM then when he was running his crystal viewing con.
Even you fall for the standard cover story, that Campaigns which produce such immense Benefit could only be the incidental result of the compulsions of greedy lunatics, despite the fact that they happen over and over again.

You observe the whole affair in meticulous detail and yet fail to include the ultimate Results of them in your analysis. And you fail to consider any of the more obvious and expected alternatives which would not have produced these Benefits, and may have instead led to ruin and collapse.