Male vs. Female Sex Drives

Great Debates
1

I’m not sure if this is a Great Debate - it seems like a Great Thought and I’m not even sure of that. I’ve never seen the following thesis put forth in writings on or discussions of the issue, but that might just mean that I’m ignorant. Anyways …

There is a widely held notion that the male sex drive is stronger than that of the female, in most cases (with exceptions of course, and any number of complicating details). There is also a lot of question as to whether this is the result of genetic/biological/hormonal factors or whether it’s mostly or all cultural.

My thinking here is that you need to consider humans as part of the larger family of primates, mammals, and animals generally. And it seems to me that in the overwhelming majority of species (if not all) it is the case that the males have a far stronger mating urge than do the females, in the absence of any culture. So it makes sense to assume that humans are not a strange exception to the rest, who share the same characteristic but for a different reason, but rather that the same basis for this difference in the animal kingdom is at work with humans as well. But what is it?

ISTM that as a practical matter, the level of sex drive of a male is a far greater determinant of the number of offspring that he will have than it is in the case of a female. For two primary reasons:

  1. A male can impregnate any number of females but a female will generally get impregnated by only one male (though she may mate with many). As a result, if there are two males, one of whom is far more motivated to mate with as many females as possible and the other who is less driven, the former will likely have far more offspring than the latter, and his high sex drive will be passed along to a lot more offspring than the percentage who receive the low sex drive of the other. By contrast, if there are two females who differ in the same manner, the difference in offspring will not be as pronounced, if any.

This factor is compounded by the face that the ability of one male to mate with many females increases competition among males themselves for the available females. This sets up a barrier to mating for males, and means that more motivation is required for a male to pass on the genes. (E.g. if you have a bunch of males fighting for the right to be the alpha male and one male decides hey it’s just not worth it, that male’s genes are not going to be passed on - the next generation will inherit the genes of the males who were willing to endure pain and possible injury for the opportunity to mate.)

  1. In general it seems to me that the physical aspect of mating act itself tends to require more action on the part of the male, with the female generally able to get by as a passive participant. So a female who has just enough of a mating urge that she is willing to go along with it will get impregnated, while a male will not pass on his genes unless he’s motivated enough to actively do something about it.

This too is compounded, by the fact that the greater the male sex drive, the lower the level of female drive that is required of her. If males are aggressively seeking out females anyway then she will pass on her genes without much interest on her part, just by lying still and thinking of England.

I would imagine that the extent to which this imbalance exists in a given species would depend on the extent to which the factors above are in play. E.g. the difference would be expected to be very big in the case of animals that live in herds with one breeding male and many breeding females. It would be smaller in animals that live as couples (e.g. some birds).

[What might be an extreme example of this is the sexual cannibalism practiced by many spiders and mantises et al. There is a lot of speculation as to why this came about, but personally I suspect that it’s just that most these creatures are cannibalistic anyway and the females are not inclined to make exceptions just for mating. In such a case most males would be advised to keep their distance, but anyone in full control of his senses is not going to pass on his genes - the only ones to do so are those willing to die for love.]

Humans are obviously closer to the pair type, but I think these factors still have a role, and would be expected to influence biology. So while it’s possible that culture plays a role here (as it does in everything else) it’s extremely likely that there is a physiological basis for the differential.

(My apologies if this is all well known and obvious etc.)

2

Even if one buys into the idea that our sex drives are shaped by our genes, this sort of logic does not hold up. First of all, there’s a difference between strength of sex drive and frequency. A man whose hormones give him a very strong desire for sex would not necessarily have sex more often because of that.

Second, even if a man had an innate desire to have sex frequently with many different women, that doesn’t necessarily mean he’ll have a large number of offspring. A woman can only have children during roughly four days out of each thirty-day cycle. Hence a man who sleeps around only fertilizes an egg 12% of the time. Even when an egg gets fertilized, the zygote often fails to implant on the wall of the uterus. Implantation occurs roughly 30% of the time. So the man would only achieve a viable fetus .12 * .3 = 4% of the time. Even when a baby gets born, prior to modern medicine only about half of children survived to age 5. So the man would only successfully pass on his genes .04 * .5 = 2% of the time. Or another way to look at it is that 98% of his attempts to spread his genes are wasted effort. By contrast, a man who remained in a monogamous relationship with a woman for a long time might be more likely to produce viable offspring.

Third, even if there were a genetic strategy that caused a man to pursue the “have sex frequently” strategy and it succeeded in producing many offspring, that strategy would be passed on to offspring off both genders.

3

I don’t think this statistic was calculated correctly. A man who “sleeps around” implies multiple women – plural. The “12% of time” would apply if all women’s cycles were synchronized.

Basically, the 2 sentences I quoted don’t agree with each other. Maybe I misread it.

4

They would certainly tend to be very strongly corrolated.

This all seems to be a mathematical error. The same factors that mitigate against fertilization in the guy who sleeps around also mitigates against it in the case of a monogamous relationship.

If we assume that a random mating results in a viable offspring X% of the time, then it would follow that someone who had three times as many random matings as someone else would have three times as many offspring.

And this is actually more true of the polygamous guy than the monogamous one, because as noted, females tend to max out. If you take a very extreme example, suppose one male mates five times a day and another mates once in five days, a ratio of 25 to one. If both of these males are mating with randomly selected females, it’s likely that the first will have 25 times as many surviving offspring as the second. But if both are in monogamous relationships this will not be so, since the one female will not be able to bear that many offspring. Essentially the law of diminishing returns applies to monogamous relationships more than to polygamous ones. (This is also apparent in the case of many professional athletes these days. :D)

Not necessarily. There are many genetic factors that affect males and females differently.

In particular, if there is some cost involved in having a higher sex drive - or even if there is some cost in whatever it is that causes the high sex drive, e.g. high testosterone levels - then there would be selection pressure on females to lower it.

5

Absolutely, after all: pretty much every species that has two genders has different mating instincts for male vs female. It would be strange if humans were different in this regard, and of course we are not.

However, I dispute the essential hypothesis of the OP, that men have higher sex drives. From the couples that I know, and have been in, it’s often the woman who desires sex more often.
I think the key difference between the sexes is not our desire to have sex, but how we pick our partners.

For a whole number of reasons (and you’ve touched on some of them), women tend to be more discerning than men. A man may look at a woman, deem her physically attractive, and then that’s it: he’d be prepared to have sex with that woman.
Women, for the most part, are slower to make that judgement and will more readily get “cold feet” about being with a new person.

6

Anatomically, the equipment is pretty similar. Studies show that male and female orgasms are similar in intensity.

Furthermore, the idea that women have a lower sex drive is very culture-specific. There are just as many cultures who regard women as having an unquenchable sex drive and men as the gatekeepers who need to keep that energy under control. If you were writing this from the Middle East, chances are you’d be crafting your answer to prove the opposite, and I’m sure you could come up with an equally believable explanation. After all, how does your theory account for multiple orgasms? Isn’t that just a waste of energy?

This is the problem with arm-chair biological determinism. When you start with the conclusion, of course you can come up with an explanation. But could you come up with an equally valid sounding explanation for the opposite conclusion? I bet you could. Congratulations, you just proved nothing.

We have hard evidence that shows that culture can greatly affect the way on feels sexuality. It’s well known that women from sexually repressive backgrounds have trouble with intimacy. And that women from sexually open societies are more likely to seek out partners, come to orgasm, etc. At this point, our culture has a much much more direct and meaningful influence on our sexual behaviors than things that happened millions of years ago.

7

Forget not the bonobo. Just because some apes are closer to the OP’s theory does not mean they all are. Compared to the Bonobo both women and men seem to have a lower sex drive, and the female bonobo has an equal, or bigger sex drive than the male bonobo.
Perhaps we would be like the bonobo if we did not have the veneer of civilization to control us.

8

I generally agree with the OP and don’t really see how the logic can be argued against convincingly. However, I would say that we are *not *necessarily talking about relative strength of “sex drive”. For example, the same arguments would make sense if we were claiming that they only showed why males are the sexual aggressors.

Taking on the dominant role in sex (beginning with initiating the act) is absolutely a typically male role with a basis in biology for all the reasons you state. On the other hand, women might have just as strong of a sex drive, except that it’s triggered by the man’s initiating act.

This is not that women can’t take on the dominant role as well. Indeed, many enjoy doing so, though for most it is the exception rather than the rule. I remember when I first started dating, my conception of sexual differences between men and women was that it was cultural, as suggested by some in this thread. But experience showed that it was obviously otherwise. Most women seem to want a dominant male sexually, regardless of how they were raised. It’s not cultural, it’s biological and the arguments in the OP are entirely reasonable and likely to be right.

9

I thought that stuff about the bonobo being all way more sexual/relaxed in comparison to chimps was being challenged, though?

10

In most species, sex is governed by females, since cooperation is essential.

I laugh at my wife’s peacocks. They spend half their life spreading their feathers, saying “Look at me. I am great stuff.”

It isn’t quite the same among humanity, but the tendacy it there.

11

This. It seems to change, at least in the West, about every century or so, between frail children who need protection and lusty witches who trick men with temptation. After all, why all the restrictions and laws on women’s sexuality if there’s not much there to reign in?

Part of the problem with discussing ‘sex drives’ is arriving at a definition – is it the drive to have heterosexual, penetrative sex, or to achieve orgasm? Because they are not necessarily one and the same for many women and some men. Where do chronic masturbators fit? Rapists? Homosexuals?

12

Women of all races and cultures lose any sex drive they might have had when I am near. I swear.

I think the question is just invalid as presented. Women in general, in every culture, do not have more or less sex drive than men, they have a different sex drive. Very different. And that is quite universal among cultures. A typical woman of any culture is much more like a typical woman of any other culture than like any man, even of her own culture.

13

This point was also made by Cat Fight.

I don’t think it’s true. From what I understand, the cultures that repress women’s sexuality don’t do this because they believe that women have unquenchable sex drives. To the contrary they do it because they believe that men have very strong sex drives, and are thus easily tempted and led astray by women.

If you can direct me to a source that says otherwise I’d be appreciative. (I can’t deny that there might be some obscure culture out there that holds what you claim, but I’d be very surprised if the major female-suppressing cultures have this attitude.)

Culture can affect the way people feel about anything. Culture can also affect the likelihood that you’ll die of heart disease.

The fact that culture “greatly affects” something does not mean that it does not have a strong genetic basis.

If you see that something appears to be fairly common across a broad array of cultures, it’s pretty strong evidence that there is an underlying basis for it.

14

Absolutely. Did you know that women choose to sleep around so that they’ll have children with a wide variety of immune systems? You can’t make this stuff up. These people could make a good living as stand-up comedians if the recession costs them their jobs as academics.

15

A man who stays with one woman and mates with her regularly is guaranteed to eventually have offspring by her, unless one partner is interfile. The man who switches rapidly from one woman to another might have no offspring or a whole bundle of them. That, however, is missing the point.

The point is that propagation of genes depends on many things beyond merely sex. If I wanted to argue that natural selection would work towards a lower sex drive for men, I could simply argue like this. A man who is satisfied to remain with one woman will be likely to help take care of her children, thus assisting in the long-term survival of those children. A man who is constantly switching partners will not stay around to help raise the children, thus decreasing the odds of those children surviving. Hence, men with lower sex drive will be more likely to have their genes passed on in the long term.

Now of course there’s no evidence for the theory in that last paragraph, but likewise there is no evidence for the theory in your OP. Both are merely speculation, so there’s no reason to prefer one over the other, nor really any reason to believe that genetics has any effect on it at all.

16

Sure, we should not jump to conclusions about human sexuality. How culture and genetics interplay is complex and I don’t think we should overly-simplify the situation to men: wanty sex, women: no wanty sex.

But to say that there’s no reason to think genetics has any effect at all, and no evidence that it does, is wrong.

After all, ultimately our sexuality is instinctive. I didn’t need anyone to tell me to want to have sex and to want to have sex with women: the human race wouldn’t have lasted very long if that were the case. Genetics obviously has an effect on our sexual behaviour, it’s really just a question of to what extent.

17

And I expect have spent some nights on the couch as a result.

18

Why would you say genetics has an effect on human sexual behavior?

Want to see the result of compulsory, instinctive behavior? Watch animals and insects that have instinctive sexual behavior.

When is the last time you saw twenty guys running down the street chasing a female, that stood and mated with the most fleet?

There is no instinctive sexual behavior in humanity. If it feels good, do it … works wonders for humanity. Candy is dandy, but liquor is quicker. And on and on.

19

The fact that genetics isn’t the *only *thing driving human sexuality doesn’t mean that it isn’t there… In fact, as a wild guess, I’d say 90% of our drive is instinctual. Do yourself a favor: videotape yourself having good sex, and then watch it like a scientist. Tell me we are not enacting an animalistic ritual that is wholly outside the realm of specific cultures.

The fact that our sexual experiences do have large and complex elements rooted in rationality, culture, and many other things, doesn’t take away from the fact that they are dominated by our evolution-carved survival instincts.

20

Can we videotape ourselves having good sex with a scientist? I call dibs on Christmas Jones.