Evolution and rape

Not so. A minimal reproductive advantage, accumulating over the generations, would have been enough. For example, say you have a population where a "sometimes rape, as opportune" gene is newly introduced into a pool of "never rape" genes. Say the "never rape" gene reproduces 99% as often per generation as the "sometimes rape" gene does. Then the "never rape" population collapses with a half-life of 70 generations --- a mere 1,400 years, which is peanuts to evolution. Exponential growth (or collapse) is pretty dramatic that way *, even without a dramatic survival difference per generation.
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For sticklers: Yeah I know, it's a logistical function, not an exponential. The overall point is the same.

In any evolutionary bottleneck, such as the 1000 population posited by the Harvard geneticists, one percent of the population would have been five individuals--across the entire planet. The point i am making about the population density is to ask "who would they have been raping?" I don't see anyone addressing the population density here.

The propensity to rape today reflects the advantages of rape throughout our entire evolutionary history --- not just this short-lived bottleneck.


During that 1000-year (tops!) bottleneck 80,000 years ago? Maybe nobody. During the rest of our evolutionary history (millions of years), when the population wasn't near extinction levels? Plenty. And the timeframe that counts here is our entire evolutionary history.

I'd say a product of neither.
Instead it is a result of objectification. Whether by learned social contract or inborn conscience, the great majority of us overcome this tendency. Otherwise rape and other crimes would be everyday occurrences for each of us. An exception may be noted in wartime, however, when politicians and priests deem it necessary to depersonalize the enemy.

This is like those phony-baloney numbers you threw up there--you assume that rape confers a reproductive advantage. But such an advantage only "kicks-in" if it gives enhanced access to resources--food, shelter, etc. You're assuming that it does, but you have no evidence to that effect, nor even a plausible argument. You are coming up with too simplistic a scenario. With a population density of 50,000 square kilometers per band (assuming a band to be 25 individuals) that would place thousands of kilometers (potentially) between bands. There is not going to be any advantage conferred if the non-rape population has the same access to resources as the rape population. More than that, the figure of 5 i used was based on one percent of half the population of 1000. Run the figure up to 10000 (which is where the 50,000 square kilometers figure derives). That's fifty individuals in the rape group--and that does not take into account males too young to reproduce or too old and weak to run down a woman. With a population of 10,000, and assuming a band size of 25, that's 400 bands. Statistically, there is a high likelihood of most bands having none of the rape group. I see no reason to assume that there would be any such advantage to the rape group before the rise of agriculture and pastoralism, and not much advantage then--unless one is talking about warfare. In the case of warfare, my objections given above apply.

By the way, there have been quite a few evolutionary bottlenecks, not just the one. That's why we have Mitochondrial Eve and Y Chromosome Adam. There was some heavy-duty bottleneck in operation then. I speculate that humanity walked a knife-edge of survival until the rise of agriculture and pastoralism.

No. Access for your sperm to female wombs is enough. And there is plenty of evidence that raping a woman gives you that.


Yes -- if bands are distributed evenly across the land mass. But that's a big "if", as I tried to illustrate with the American-Elm example.


Nevertheless, non-bottleneck eras of evolutionary history are far more common than bottleneck episodes. Our genetical propensity to rape is shaped by all of our evolutionary history, which in turn is dominated by non-bottlenecks.


No there wasn't. Mitochondrial Eve and Y-chromosome Adam have nothing to do with bottlenecks in our evolutionary history. You want to read this up in Richard Dawkins: An Ancestor's Tale, which even Farmerman agrees is an excellent book on issues like this.

Mckibbin et al,(link below) have stated that;
the investigation of the significance of rape in humans does not signify the approval of the practice anymore than studying cancer means that the investigators are in"favor" of the disease.
http://www.mta.ca/~ogould/FLIPS/Flips5McKibbin.pdf

PS , the 1000 genomes project and the HApMap projects are slowly discovering that maybe this "bottleneck" may have been just a local occurrence since there are several populations that retain almost 100% of the African genetic diversity.
Theres always reason to be skeptical of "Science" that is presented on the History or Discovery Channels. The problem with just looking at the Y and Mn haplogroups is that they are only a statistical inference of the two supr hapgroups. There are 20 other regional haplogroups , many with much greater genetic diversity.

Farmer: Sometimes the findings of evolution reveal stuff that isn't so comfortable admit or to live with.
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So too with history, Farmer, which is precisely the reason you fled to IGNORE.

That's one interesting paper. Thanks, Farmerman!

Access to a womb only counts if it produces a child which survives to reproduce. At any event, all of your comments are predicated upon two undemonstrated assumptions--that there was a propensity to rape and that it conferred an evolutionary advantage--neither of those claims are established. It seems to me that you're involved in question begging. If the groups were not evenly distributed, a good point which you make, that can also mean that there were many, many groups without rapists, or not in proximity to groups with rapists.

I fully acknowledge that i need to do more reading, and claim no expertise. My biggest problem here, with the claims of this paper and with your comments about rapists is the assumption with no evidence that rape would have conferred an evolutionary advantage. I also remain skeptical that there was any significant incidence and prevalence of rape without any evidence being presented.

I was glad to see the paper from Florida Atlantic University, particularly as they stated their premises at the outset--one of which, however, was implicit, but not stated, and that is that rape was as common in ancient times as it is now. As i may have stated (i'm not going back to look now), it is not reasonable to consider human behavior constant over the boundary between true hunter/gatherer cultures and agricultural/pastoralist cultures. The rise of agriculture/pastoralism had a truly dramatic effect on human populations, and crucially, on population density. I see no reason to assume that human behaviors since that watershed set of events can be casually atrributed to humans before those events. In short, i remain unconvinced--if for no other reason than that we have so little evidence of human behavior before the rise of agriculture.

That's right. Access for your sperm to a womb sometimes produces a child, even if the access takes a heinous form such as rape. By contrast, declining to access a fertile womb never produces a child, even if you decline it for noble reasons such as respect for women. Accessing the womb, then, is always more likely to produce a child than not accessing it --- including in the case of rape.


My point is that if two stone-age groups are in close-enough proximity to compete for food and shelter, warfare between them is likely at one time or another. And once you have warfare, you can bet there will be warriors raping --- and impregnating --- their enemies' women. Such behavior, sadly, is a human universal. And to the extent that it is influenced by genetics, we have probably inherited the genes that furnished it.


As Max Dancona pointed out earlier, rape has an evolutionary advantage because sex in general has an evolutionary advantage, and rape is a form of sex. Do you seriously lack sufficient evidence to believe that sex has an evolutionary advantage?

That is inaccurate. Here is what I said in my very first post:


Notice: "to the extent that". To the extent that genes influence a man's propensity to rape women, I have inherited this propensity from all my ancestors who were conceived by rape. And since I have millions of ancestors, it statistically is nearly certain that some of them have been conceived by rape. Other than that, I took no position on the magnitude of the effect.

Not committing rape is not evidence that a man declines to "access a womb." I wonder what you mean by "stone age." A lack of potential resources was never a problem for out ancestors before 10,000 years ago. Their problems were gathering and hunting sufficient food to store for the winter, and competently storing it. There is abundant genetic evidence that groups continued to leave Africa until quite recently in human history, which suggests (no data for certainty) that there may not have been abundant resources there. But the people who occupied Eurasia were following the vast herds, millions upon millions of individual animals, who grazed the periglacial steppes of Eurasia. I seriously doubt that there was ever warfare due to competition for resources. Although the land was bountiful in season, it still required a great deal of work to hunt, gather and store, as it did to gather and stockpile fuel for the long winters. There is an energy equation which people with little real knowledge fail to understand when imagining our pre-agricultural stone age ancestors. In the winter, everything you do out of shelter needs to return, or contribute to returning, all the calories you burn doing it. In season, you need to be taking in two, three or four times as many calories as you burn up, because you have to store it for winter (or the rainy season, in warmer climates). The energy equation doesn't leave any time fore warfare. You also cannot risk serious injury or death for any members of your band. Everyone who is not too young or too old to walk needs to join in gathering forage foods. Every healthy adult (meaning everyone about 12 or 13 years old or older) needs to engage in hunting. Those not skillful or strong enough need to go along to help butcher the kills and carry the food back to the shelter. I seriously doubt that there were any warfare like activities and that killing and raping would have been very rare, and limited to chance encounters. Competition for resources is a doubtful cause because, with proper management, there were more resources available than were needed. The imperative factor was the energy equation.

Anthropologists universally agree that warfare was a product of agriculture and pastoralism. You need logistical support to go war and to maintain a war. In the Maori Musket Wars in New Zealand in the early 19th century, the early conflicts usually ended with the slaughter of the losing side. However, cheiftains quickly realized that they needed to keep the vanquished alive and to enslave them, because they would otherwise not have enough food to make it through the rainy season. Enslaved people were used to grow the yams and potatoes (potatoes introduced by the Europeans) which were needed for logistical support in continuing warfare and for the tribe to survive after the growing season. Our pre-agriculatural ancestors did not have the luxury of such surpluses. Those only came with invention of agriculture.

Do you seriously think that rape was an important form of sex before the rise of agriculture and the concomitant birth of warfare? Do you seriously believe that the rape of the women of vanquished enemies routinely produced significant numbers of children with the genes of the victors who would themselves survive to reproduce. I see rape outside of warfare as simple opportunism, and opportunism have evolutionary value without reference to sex, whether consensual or rape. Max's claims are, by the way, speculation for which he provides no more evidence than do you and the rape as evolutionary product crowd.

He declines access to the particular womb whose owner he's not raping. And since sperm, unlike wombs, are abundant, declining to rape this particular woman will generally not help him with other opportunities to have (consensual) sex.


That's not what Wikipedia says in its article on hunter/gatherer societies. It says this is an ongoing disagreement among the scientists who are in a position to judge, and provides sources to document the disagreemen:


Notice: some archaeologists (but not all). Many anthropologists (but not all). There is no such thing here as the universal agreement that you claim.


Yes I do. As Farmerman pointed out in an earlier post, coercive sex happens among all of the Great Apes, and is common in all of them except Bonobos. Why would humans, this glorified third chimpanzee subspecies, be an exception? And why would this exception be restricted to stone-age humans (who lived in similar environments as the other Great Apes) but not agricultural and city-dwelling humans (who live in completely different environments)?

So, you apparently think that rape is the only means of "accessing a womb." I acknowledge that i should not have used the term universal. But by that same token, these jokers should not be saying that such conflict were ubiquitous, given that ubiquitous means found everywhere. They seem to have little concept of population of density or the energy equation, too. I've noted that some violence may have occurred in chance encounters--that's a far cry from organized warfare. Those comments also ignore the much higher population densities of hunter-gatherers in the contemporary world as compared to millennia gone by.

I don't think that comparing primates with our ancestors is valid, because primates are not engaged in the sorts of cooperative activities which were essential to human survival. I consider that a failed analogy.

Really, rape is not the only form of procreation, and i think you have reached the point of arguing for arugment's sake. I've not said these folks are wrong, once again, i'm just saying "not proven." I'm done talking to you, Thomas, you've departed into surreal realms.

The idea that violence is NOT in our genes is far from being "universally agreed":

From Wiki:
http://en.m.wikipedia.org/wiki/Seville_Statement_on_Violence

The Seville Statement on Violence [...] was adopted by an international meeting of scientists, convened by the Spanish National Commission for UNESCO, in Seville, Spain, on 16 May 1986. It was subsequently adopted by UNESCO at the twenty-fifth session of the General Conference on 16 November 1989. The statement, then known as a 'Statement on Violence', was designed to refute "the notion that organized human violence is biologically determined".[1]

Core Ideas [...]

"It is scientifically incorrect to say that we have inherited a tendency to make war from our animal ancestors."
"It is scientifically incorrect to say that war or any other violent behaviour is genetically programmed into our human nature."
"It is scientifically incorrect to say that in the course of human evolution there has been a selection for aggressive behaviour more than for other kinds of behaviour."
"It is scientifically incorrect to say that humans have a 'violent brain'."
"It is scientifically incorrect to say that war is caused by 'instinct' or any single motivation."
The statement concludes: "Just as 'wars begin in the minds of men', peace also begins in our minds. The same species who invented war is capable of inventing peace. The responsibility lies with each of us."[2]

Founding scientists [a lot of psychologists... paleontologists are very few and far between]

Criticism

Steven Pinker has criticized the Seville Statement as being an example of the moralistic fallacy.[3] Some scientists believe both evolutionary psychology and neuropsychology suggest that human violence does indeed have biological roots.[4] [5]

Steven Pinker has used the Seville Statement as an example of the idea of biological determinism, the incorrect idea that genes are solely responsible for any of our behaviors.[3] A 2008 article in Nature by Dan Jones stated that "The decades since have not been kind to these cherished beliefs. A growing number of psychologists, neuroscientists and anthropologists have accumulated evidence that understanding many aspects of antisocial behaviour, including violence and murder, requires the study of brains, genes and evolution, as well as the societies those factors have wrought." Evolutionary psychologists generally argue that violence is not done for its own sake but is a by-product of goals such as higher status or reproductive success. Some evolutionary psychologists argue that humans have specific mechanisms for specific forms of violence such as against stepchildren (the Cinderella effect). Chimpanzees have violence between groups which have similarities to raids and violence between groups in non-state societies. Several studies have found that the death rates from inter-group violence are similar for non-state societies and chimpanzees.

Just to clarify, in this discussion I am considering "rape" to be synonomous with "coerced sex". That means sex any time that one of the participants is being forced.

The idea that this only happens in the context of war is clearly wrong.

Men with great power often force women within their communities to have sex with them. You see this in all sorts of cultures. You see this in ancient literature including the Bible.

I think this counts as rape (in the modern sense).

Some cultures support this. Many cultures have child brides and arranged marriages. Our own culture forced a wife to have sex with a husband until recently, the idea that "spousal rape" is a crime (or even a concept) didn't exist and is still rejected by many religious communities.

I would also point out that coerced sex is fairly common in the animal kingdom. This is clear evidence that there is an evoluationary advantage.

And, just to clarify, I did not say it only happens in the context of war. I was responding to Setanta's point that rape is harder to get away with, and hence rarer, in a family tribe of hunter-gatherers than it is in a modern, anonymous city. My response to his point is that even if we suppose it's true, there still is enough inter-tribal warfare providing opportunity and motivation to rape. I never suggested that rape only happens in the context of war.