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Monogamy May Have Evolved To Prevent Infanticide
sciencehabit writes "Human males and females have a strong tendency to live together in monogamous pairs, albeit for highly varied periods of time and degrees of fidelity. Just how such behavior arose has been the topic of much debate among researchers. A new study comes to a startling conclusion: Among primates, including perhaps humans, monogamy evolved because it protected infants from being killed by rival males."
and killing offspring is directly opposed to the core of evolutionary theory
Unless those offspring are in direct competition for food and reproductive access with your offspring. Then it makes a lot of sense evolution-wise.
Been there, done that.
What a myopic view. You have a lot to learn about evolution, and even more so about dogma and religion. "Science" an esteemed science journal would unlikely stoop to sensationalize. Where do you get your bias -- FOX?
No, science is not religion, in the way you're implying it is. Science works by creating theories (either from educated guesses or observations, often both) and testing them.
If it can't be tested, it's not science*.
*Of course, one thing is not being capable of measuring something - the fact that light is affected by gravity took a while to test, for instance. That doesn't make it impossible to test.
Clearly you didn't read the article. The very study linked in the summary specifically compared 230 primate species, some of which are socially monogamous and some of which are not. And it explains why it *hasn't* evolved among all of the fairly similar species in the study using a model based on the infanticide rate.
There are almost certainly things to be picked apart in the study, but you need to understand the basic premise before you can start on that track.
and killing offspring is directly opposed to the core of evolutionary theory, which rewards the widest possible range of mates to guarantee diverse genetic combinations and the maximum chances for survival and spread of strong genes.
This may come as a complete surprise to you, but there do exist plenty of creatures out there that do kill the offspring and still haven't become extinct and there do exist plenty of creatures out there that do not kill their offspring and only mate with one or very few partners and still haven't managed to become extinct. Hell, there exists atleast one specific one that doesn't mate at all and produces only perfect clones of themselves, and still haven't become extinct. The point is, you cannot just lump different survival-strategies together like that and deny the existence or even the possibility for anything other than your one chosen one; what works for one type of a creature may not work for another, and the nature has the tendency of throwing all sorts of types of stuff on the wall and seeing what sticks.
Because there's no "design" to evolution. Whatever works, works. And there's not one "right" way to evolve. There's no reason for a feature that evolves in one species to independently evolve in other species (although it's possible.)
assert(birth_date<time-86400)
Just because someone else has a different hypothesis doesn't mean this one is wrong.
"First they came for the slanderers and i said nothing."
Humans are not brought into heat by the absence of young, and killing offspring is directly opposed to the core of evolutionary theory, which rewards the widest possible range of mates to guarantee diverse genetic combinations and the maximum chances for survival and spread of strong genes.
Male squirrels will gnaw the nuts off their male offspring if the mother neglects to defend them constantly. Last I checked squirrels seemed to be enjoying reasonable reproductive success ;-)
primates tend to be in bands
Except for the ones that aren't, like orangutans, a close relative of ours.
Mogamy happen because it takes a long time to rise the offspring, and it needs the support of both the female and male
That's one pressure. TFS mentions another. There can be more than one reason, and there usually are.
Tic-Tac-Toe, Global Thermonuclear War, and relationships all have the same winning move.
Can you explain why you *didn't* get into a car accident in the last month? What was it that you did that nobody else who got into a car accident last month did, to cause you to avoid all the accidents that could have happened?
You could say that Bill was drunk, or Alice was texting, and that's why they got into car accidents, but that doesn't explain how every single person that drove drunk or texted while driving didn't get into an accident.
What kind of explanation were you expecting?
Birds clearly have an advantage by being able to fly. If I said "Flying is not advantageous, because if it was, all organisms would have evolved to be able to fly", would that be convincing to you?
It takes a female chimpanzee 4 to 5 years to teach her offspring enough to survive. During that time, she does not come into heat. Humans, on the other hand, can have babies about once a year. A single female could not raise them all on her own without some help. Today, we call that helper a husband and father. Monogamy means more babies.
That's not what they said about Welfare Queens.
Here is a quote from Euripedes a writer from Ancient Greece where they had polygamy:
A second wife is hateful to the children of the first; A viper is not more hateful.
Monogamy evolved because it makes great furniture.
The study (and the linked article) go far beyond "lots of stuff could have worked and this is the one that must have come up." What is says is that monogamy hasn't evolved in other species because they don't practice infanticide. And why is that? Because big-brained animals take a long time to develop, so the young are defenseless.
I believe evolution happens, both historically and currently, and on scales both grand and small.
But I'm tired of so-called scientists making news stories out of un-testable speculations about how something or another could have been a factor in our evolutionary past.
That kind of speculation is for late-night living-room talk, not scientific journals.
How does monogamy change who is in competition with whom? There is no evolutionary mechanism to enforce monogamy. From a purely genetic standpoint there is no benefit to monogamy for a strong male.
Articles like this are just freeze dried beef pasta boiled up in 100 gallon vats and thrown to the neckbeards who gobble it up while slathering vaseline and yanking each other off.
Shit isn't even pretending to be science any more. It's just some asshole in a lab coat leading a revivial in a Kentucky tent.
The argument is that your statement about a strong male being better off without monogamy seems right but isn't, because if strong males fail to stick around and ensure the children they conceived survive to reach adulthood and carry on the cycle, it won't happen, and their "strong" genes will be wiped from the face of the earth.
-1 Uncomfortable Truth
"Human males and females have a strong tendency to live together in monogamous pairs"
As much as they have a strong tendency towards not being able to afford harems.
Now, mod me down freely. My karma can't get any worse...
No, it did not say that other species practiced infanticide. It said that infanticide was much more detrimental to us (and what had evolved into us) due to the extended period of helplessness during infancy. Infanticide was much too expensive for us than it is for lions and such.
Boobies never hurt anyone. - Sherry Glaser.
why it hasn't evolved in lots of other species.
IANAA (I am not an Anthropologist) but I'm going to take a stab in the dark and hypothesise that it is because human offspring require a much bigger commitment of time, energy and resources before they can fend for themselves, than the offspring of pretty much any other species on the planet. Mind you monogamy is not exactly some sort of genetic trait we have evolved. Here in the west it is largely a cultural phenomenon that the christian church has popularised. There are plenty of cultures around the world where even fairly low status males can have more than one wife and there are also cultures where wives can have multiple husbands. So it is probably more accurate to say that humans evolved to be highly social and to engage in highly structured very long term bonding to form monogamous or polygamous families, partly to minimise infanticide and to maximise the odds of their very time and resource expensive offspring reaching adulthood.
Only to idiots, are orders laws.
-- Henning von Tresckow
But the point is, it's not productive to discuss what "could be" explained by evolution, since that is practically everything and anything. You have to stick with the fossil record, DNA, and (where possible) direct experiments.
I think that it is "Evolutionary Psychology" that is the religion -- not science.
If you said, "Evolutionary Psychology is ritualized Nuttery, like Economics," then I would be in complete agreement with you.
Humans, on the other hand, can have babies about once a year.
Women who nurse exclusively on average do not get their periods for 14-15 months after childbirth. Some get it right away, some go 2-3 years, but 13-16 months is the average, if they are nursing.
What is says is that monogamy hasn't evolved in other species because they don't practice infanticide.
What I was thinking when I posted was of all the nature documentaries where a male adopts a new female into his "harem" and promptly kills her young. A few weeks ago I saw a somewhat unnerving film of a zebra doing that, picking up the foal by the neck with his teeth, and bashing him down onto the ground. I believe lots of other species do it too, and I've seen films of several.
Sheesh, evil *and* a jerk. -- Jade
Women cheat just as much as men. Your argument still holds--it makes just as much sense for the female to cheat as it does the male, namely the opportunity to mix your genes with someone else's--you just need to excise some of the sexism.
Science works by creating theories (either from educated guesses or observations, often both) and testing them.
If it can't be tested, it's not science*.
Sorry to seem pedantic, but science works by creating hypothesis and testing them, not theories.
Theories need to be supported by a vast body of evidence, and should provide both an explanation and the ability to make falsifiable predictions. They start out as hypothesis, however once experimentation and observation bear out the hypothesis, and sufficient data is accrued to show that all the expected data fits the hypothesis, and that predictions made by the hypothesis continue to be valid, then the framework derived from the hypothesis can be called a theory.
The point being, once something in science is considered a theory, you're long past the creation and testing stages (although there is nothing wrong with continuing to validate new data against existing theories; and obviously once new data is available some theories become either no longer valid, or only valid for certain systems of constraints). What you were talking about above are hypothesis, and the difference is critical to make in this world of vast scientific illiteracy.
Yaz
" From a purely genetic standpoint there is no benefit to monogamy for a strong male."
From a genetic standpoint Monogomy is a disadvantage for a strong male. A strong male should be humping everything in sight to spread his genetics far and wide.
That is how it works in nature. A male lion has a pride of females for this exact reason.
Do not look at laser with remaining good eye.
It's used as a warning to others, so far Canada hasn't tried to invade us. That means it's working!
Do not look at laser with remaining good eye.
Oh, anonymous person on the Internet is such a big tough man. Catch a whiff of that musky manliness. But only a whiff! For should you inhale too deeply, the raw might of their being may overwhelm your soul!
Listen, everyone! You should accept how this person chooses to address YOU. The Cat has obviously shown his superior intellect and grasp of reality. Do not let the display of raw emotion intimidate you. Instead, be in awe of such power unleashed.
This stunning specimen of human perfection deserves... NAY, DEMANDS ... your respect and attention. And you will give it to them. For they are... The Cat.
No sig for you!!
Young women are attracted to young men who take unnecessary risks in extreme displays of their adult skills. Today it's smoking the wheels of cars, not so long ago it was jumping out of trees onto wild buffalo. Every hero in every action movie does the same thing, no matter what is thrown at the hero he gets up and keeps going, no matter what the hero blows up or how many bullets he shoots no innocent bystander is ever hurt.
Young women are not attracted to 'idiots' that crash and burn, they are attracted to 'heros' who's skills and strength keep them alive and healthy despite the odds. It's not a conscious thing in either sex, "cheating death" is an integral part of the human ritual of finding a suitable mate, it's so deeply ingrained in humans that a males brain chemistry will reward "cheating death" with feelings of elation, pride, and self-satisfaction.
Looking back as an old man who had the luck to survive the motorbike ritual (among others), young men really do behave like peacocks, the things they unconsciously do to attract a mate are even more dangerous to the individual than that ridiculous tail is to the peacock. At the end of the day it does make our societies (if not our species) better suited to the civilizations we invented. We are continually evolving and are in a feedback loop with the environment we have created for ourselves, not unlike the termite and it's air-conditioned fungus farm.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
but neither does it forbid it.
you're quoting it without comprehending it, and missing an important word.
the word is "necessarily", as in "necessarily imply".
the statement is cautionary in nature, not regulatory. ie, not absolute.
as in: "sometimes people commit the opposite fallacy – dismissing correlation entirely, as if it does not suggest causation."
The guy who said the election was rigged won the presidency with the second-most votes.
Perhaps not. Maybe the mods objected to the misogyny.
It's used as a warning to others, so far Canada hasn't tried to invade us. That means it's working!
Been there. Did that.
Surrender of Detroit
Yaz>
I'd like to hypothesize that a lot of people are hung up on finding an evolutionary answer for everything. Sometimes things just happen in a species without there being an evolutionary advantage. Species are not hyper optimized. Sometimes things are just side effects. Sometimes I get a feeling that people like to anthropomorphize evolution, replacing a deity that designs with specific reasons and goals with a system that does the same thing. Especially with very fuzzy things like behavior.
Ie, I've heard people discussing the reason for grandmothers. This is a silly concept, unless your view of evolution is that it is a system that optimizes organisms. Maybe grandmothers exist because humans live longer than they used to, no need for a hand waving explanation. Others want to have an evolutionary "reason" for homosexuality. Yes, it's not a nice thought to think that it's a biological mistake, but it's certainly easy enough to think that it is because some genes are expressed at a certain time that caused various hormones to be produced at a particular time in development, and as a side effect of this slight variance in timing you end up with an organism that does not fit the standardized phenotype. May as well ask what the evolutionary advantage of preferring red heads over blondes is.
Humans are extremely complex, in a chaos system way. We have plenty of attributes that are not optimal for reproduction of the species, but they exist because they don't kill us off. But evolution is dumbed down for teaching purposes, even in undergraduate classes. People still recite "survival of the fittest" as if it's some sort of law. Others talk about "higher" species or "more evolved", which is nonsense.
As for monogomy, research among cultures around the world do show a consistent view that is "mostly" monogamous. Ie, serial monogamy with occasional cheating on the sly. That's universal. Yes, there are examples of cultures with polygamy, but even in those societies the polygamy is rare and when it occurs it is due to societal pressures (ie, a severe shortage of one gender, usually men due to wars), and at other times is restricted to just high class members of society (ie, to have more than one wife is proof that you are wealthy).
This is how it works in nature - sometimes. The strongest male being the only one that reproduces is not at all the most common reproductive strategy. Even when it does occur, sometimes there are smaller males waiting for the top two to go off and fight so that they have a shot at the females (sea lions).
With birds it makes sense for the male to stick around until the offspring leave the nest. But they still quite often will stick around the next season as well. There's no simplistic evolutionary reason for them to not try and find a different partner next year, or for them to stop breeding altogether if their partner dies.
The more demanding infant seems like all the more reason for an interloping male to kill it.
I may be misunderstanding your argument, but the premise of the study is that monogamy developed to stop interlopers for this reason.
There is no general answer to whether you will get more bang for the buck from defense (sticking around to guard your young) or offense (going out to eliminate the competition). It depends entirely on the situation. There is simply no utility in trying to reason out an answer based on basic evolutionary principles. Many narratives are plausible. The point of gathering evidence is to see which one actually occurred.
Well, the Creationist has an easy argument on this one. God made Adam and Eve, so that's the design.
Peter predicted that you would "deliberately forget" creation 2000 years ago...
Long ago, I was at a good friend's house waiting for him when his wife asked me to help her with some small task that her husband normally would have done. So I did the work, and when I was done she thanked me, saying "The only thing better than having one husband is having two husbands!"
I immediately replied, "The only thing worse than having one wife is having two wives."
No, he's correct.
That is complete nonsense. We are seeing the results of social pressure to be monogamous; it is not genetic.
Just look at history for 1000's of examples to the contrary. Monogamy is a very recent phenomenon.
These studies are a huge disservice to humanity that attempt to "force" a point of view on people.
It's also reasonable to assume that infanticide may have more attribution to infant mortality than deliberate action by another male.
People who produce this junk are really missing so much of the picture.
im a hardcore atheist who is definitely pro choice and have absolutely no part in any cults, and if i had mod points, i would have modded you down as well. it is obvious that you are being a flamebait, either that or your parents should have washed your mouth out with soap when you were younger.
Being a father of 4, I love those whipper snappers like crazy, even when being annoying, noisy, crying, mean. Other people's kids? Little turds can go the hell if they act like that. Shut them up and get the them the F outta my face. Of course I never say that to anyone and have the higher level thinking to take a step back and get some sympathy. But the initial instinct is there, hating other peoples' childrens' antics. Perhaps a latent instinct still at play.
Yeah, yeah, misogyny is the buzz-word of the day ... which really means "if you challenge anything that could be construed to challenge a woman in any way for any reason, I'll pull out the misogyny card so that I don't need an argument". The term is about as robust as "discrimination" (which means "to choose"). The power of words...
Anyway, a friend of mine taught in Papua New Guinea for about 10 years back in the 80s. He lived there for that time (other than the occasional holiday). He was not a missionary - he was there for education programs. This is roughly what he told me a few years back (and re-confirmed when I asked him again)...
The men tended to stay with the men, the women tended to stay with the women. There was only a loose "sexual" association between men and women - and the offspring (when the men got randy) belonged to the community rather than a couple. The kids would go with whatever adult they wanted to stay with, sometimes months at a time. Over time, this social structure was forcibly changed by the missionaries to reform these hethens.
Now, this social structure was not monogamous in ANY sense of the word and involved little or no infanticide. Interestingly, it mimics (loosely) some aspects of Indonesian culture, although Indonesian culture has also been "westernised" to a degree, although I did see this sense of "community" that you don't get in the west ... front doors left open, people just coming and going into other's houses, kids staying at other families' house for weeks at a time - it was amazing to see.
Feel free to call me a misogynist too, since it's popular to throw buzzwords around. Whenever I hear the "m" word, my "wanker alert" light goes off.
In a social species, culture (or peer pressure if you want to call it that) is a selectable trait which can influence the evolution of a species. The trait is a passed on through learned behaviour rather than genetics
Modifications in behaviour of members of a group can directly affect the survivability of the entire group relative to other groups of the same species.
The obvious example being disease control, if there is a communicable disease which relies on certain behaviour by individuals to spread through a group and one group in an area doesn't follow that behaviour has a better chance of survival, it could be sexual practices, dietary practices (i.e cannibalism for ritual or nutrition) etc.
These comments are my personal opinions and do not necessarily reflect the opinions of the other voices in my head.
We are seeing the results of social pressure to be monogamous; it is not genetic
If you think this means that it's not evolved behaviour, then I can only assume that your education in evolution stopped just after Darwin. Try picking up a textbook written in the last 30 years. I'd recommend The Extended Phenotype (published in 1982).
I am TheRaven on Soylent News
Besides, most realistic women aren't really impressed by this kind of stupidity as well... or if they are attracted to it they also behave in a reckless manner.
So? The idiots doing this stuff don't really care if the girl who sleeps with them as a result is "realistic" or "reckless."
Not really. In a species with a relatively long gestation period and few offspring per litter, the limiting factor in population growth is the females. A primate female can only produce a very limited number of children over her lifespan (especially compared, for example, to rodents) and a significant fraction of those won't survive to adulthood anyway. A reproductive strategy that involves killing even more of them off is going to leave the tribe very weak and so the survivors may have benefitted from the process, but that only matters in evolutionary terms if they survive long enough to breed, and do so in comparable quantities to others with different strategies.
I am TheRaven on Soylent News
They did a statistic among many primate species. But the conclusion that this applies to humans is propably wrong:
The closest relatives of humans - chimps and bonobos - don't live in monogamous pairs.
Humans share genital features and gender relative body size with bonobos and chimps but not with monogamous primates like gibbons.
And pure hunter gatherer societies that exist know don't live monogamous.
It is very likely that monogamy in humans was triggered by agriculture. It really doesn't make much sense for a population living in small communal groups without property.
http://www.sexatdawn.com/
The research presented in the article might be sound for monogamous primates, but that group of animals does not include humans.
Here is a citation that claims the opposite:
https://www.facebook.com/sexatdawn
Indeed.
Imagine you are living in a small group of foragers that share all their food and take care of the children together and have next to no property. How exactly could mating with only one partner help you raise your child or sustain food supply? It is also hard to imagine how infanticide could be prevented by monogamy in such a context. A better strategy for a female to avoid infanticide would be to regularly mate with most males so that all males might be the father of each child. And actualy that is what is observed in many pure hunter gatherer societies.
Gorilla, Gibbons and other primates only mate to create offspring. They only copulate a few times per pregancy. Chimps, Bonobos and humans however copulated thousands of times per pregnancy. Sex in these species is not only used to create offspring but also for communication and as a tool to form bonds within a group.
That's the drawback of the mod system, sometimes it reinforces a cultural/sexual/religious/political bias to someones personal agenda, rather than modding the content.
Personally I think monogamy happened because, after the sex, now you have to see to the needs of two or more screaming ,weepy, hormonal women who want to eat, have new clothes, go to the river/fire/gathering NOW! Right damn NOW! Early man could even see the need to filter this down to one at a time in spite of sex.
Then Cheating was born, which later spawned lawyers, so even a good fix still has an unavoidable drawback.
*Repent!Quit Your Job!Slack Off!The World Ends Tomorrow and You May Die!
It's worth noting that one of the reasons for severe decline of lions has been slowness evolutional response to human hunting factor (they seek mainly alpha males). Essentially every time one dies, the entire pride suffers a bout of infanticide, which is the key reason for decline of lions in the areas where they are hunted. If it was just alpha male deaths caused directly by humans, lions as species would have far less problems.
It's a pretty good microcosm of small tribal community and is somewhat relevant to humans as well.
Because contraception has been invented and the poor don't use it so much. The rich still get laid a lot more.
"When information is power, privacy is freedom" - Jah-Wren Ryel
faggot
Incidentally, the study also explains why gay people are less monogamous: there would be no kids to protect from infanticide...
*ducks*
I am not arguing against the evolutionary pressure.
My original post was to "Black Parrot" who said "But that doesn't explain why it hasn't evolved in lots of other species."
I was illustrating with my car accident analogy that you don;t need to explain why things *don't* happen with that kind of specificity.
The "But that doesn't explain why [monogamy] hasn't evolved in lots of other species." argument is analogous to the "But that doesn't explain why other safe drivers still get into car accidents" argument.
I don't know if you've yet figured out that I don't buy this argument.
I am saying that it is easier to explain why things happen than it is to explain why they don't. You can probably explain what events lead you to meet and marry your wife. You probably can't explain why this failed to occur with the other 3.5 billion women on the planet to the same specificity.
Any explanation like "I liked her Australian accent" has some truth to it, but it's not the whole story, because lots of girls have Australian accents
You can try to explain why humans have monogamy without incurring the burden of explaining why every other species doesn't given the adaptive qualities of lower rates of infanticide. "It just didn't happen" is a perfectly reasonable explanation for why an improbable thing didn't happen.