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X-rated worm movies reveal sex secrets - Comments

Hendrix is my gOD's Avatar Comment 1 by Hendrix is my gOD

By watching countless hours of hermaphroditic worm sex, Lukas Schärer and his wife Dita Vizoso, evolutionary biologists at the University of Basel in Switzerland and their colleagues, have discovered evidence for a theory that has eluded testing for nearly a century: sex shapes sperm.

It's a tough job, but somebody's gotta do it.

Wed, 12 Jan 2011 14:34:37 UTC | #577157

Philster61's Avatar Comment 2 by Philster61

Perhaps they need to get out more.....

Wed, 12 Jan 2011 14:43:47 UTC | #577164

PhilipK's Avatar Comment 3 by PhilipK

Hmm, I usually envy scientists, but...

Wed, 12 Jan 2011 14:49:05 UTC | #577170

hungover's Avatar Comment 4 by hungover

"males eager to mate and females more concerned with finding a superior partner"

I thought this was an old fashioned idea now ie females are at least as promiscuous as males in many species.

Wed, 12 Jan 2011 14:53:50 UTC | #577176

crookedshoes's Avatar Comment 5 by crookedshoes

Sex shapes sperm?

Insert (pun intended) filthy joke here _____________________....

But remember, individuals do not evolve, populations do.

BTW,

I think that if sex shaped sperm we'd expect some individuals in a given population to have slightly different sperm. Either different sperm in the same individual (like a black and white shake) or different from the rest of the population.

Here's the problem.... I do not know if this is what we find.... or not.... I am not at all well read on different species sperm...

I dop know that humans have different sperm. Some swim in tight circles and "flank" the straight swimmers... Taking the brunt of the inhospitable environment and "blocking" for the better swimmers...

Anyone know more about this? It is pretty interesting, but I fear I have just advertised my ignorance.

Wed, 12 Jan 2011 15:17:08 UTC | #577189

LaurieB's Avatar Comment 6 by LaurieB

Crookedshoes,

Last summer I read a book by Robin Baker called Sperm Wars. Couldn't tear my eyes away from it. Neglected responsibilities just to keep reading. I used to think that sperm wandered aimlessly in the uterus like a bunch of dumb clucks and by some stroke of luck one of them would happen upon an ovum. Seems I was mistaken. Sperm competition, according to Baker is intense and I now compare an ejaculate to a well tuned sports team with its offensive and defensive members who proceed towards a goal and deal with the opposite team in a take-no-prisoners fashion (in the case of the presence of the ejaculates of more than one male for example). Think about the situation from the perspective of a female. If she has sex with two or more males in a short time period and if she's fertile, she will create a sperm war where the most fit sperm reach their goal at the expense of the less fit sperm. Win for her.

hungover, Are women "at least as promiscuous as men"? Explain please.

Wed, 12 Jan 2011 16:14:33 UTC | #577223

crookedshoes's Avatar Comment 7 by crookedshoes

LaurieB, Thanks for the clarification as well as the book suggestion. Any time I run across an intelligent person (like you) offering a book and the endorsement includes "I neglected responsibilities..." I am going to read it!!!!

I also have heard these things (just in passing) and that's why I chose to say "blocked for" and "flank" (football terms).

How can one gender be more or less promiscuous than the other?

Oh, and (just a partial song here)

There are Jews in the world. There are Buddhists. There are Hindus and Mormons, and then There are those that follow Mohammed, but I've never been one of them.

I'm a Roman Catholic, And have been since before I was born, And the one thing they say about Catholics is: They'll take you as soon as you're warm.

You don't have to be a six-footer. You don't have to have a great brain. You don't have to have any clothes on. You're A Catholic the moment Dad came,

Because

Every sperm is sacred. Every sperm is great. If a sperm is wasted, God gets quite irate.

Every sperm is sacred. Every sperm is great. If a sperm is wasted, God gets quite irate.

Let the heathen spill theirs On the dusty ground. God shall make them pay for Each sperm that can't be found.

Every sperm is wanted. Every sperm is good. Every sperm is needed In your neighbourhood.

Hindu, Taoist, Mormon, Spill theirs just anywhere, But God loves those who treat their Semen with more care.

Wed, 12 Jan 2011 17:13:59 UTC | #577254

LaurieB's Avatar Comment 8 by LaurieB

I wasn't raised in the Catholic church and so this whole idea that every sperm is sacred and incredibly valuable is extremely strange to me when encountered as an adult. It certainly flies in the face of what I've observed which is that apparently there is an overabundance of human sperm to be had.

Men don't act as if they have a limited number of ejaculates in their lifetimes, do they? Seems to me that they are happy to distribute their genetic material far and wide. Men are known to have sex even with other species and even with inanimate objects, right? Production of ova on the other hand is much more limited. Ova are rare compared to sperm and this is what makes them super valuable. I'm not sure about this but If I looked into the price of a sperm donation and the price of a donation of ova wouldn't the price of the ova be much higher than the sperm? Add to this the biological cost to females of pregnancy, lactation, risk in labor and delivery, and provisioning of offspring, is it surprising that women would be less promiscuous than men? Other factors enter into this but just the simple facts of reproduction are enough for a woman to slam the brakes on the prospect of sexual activity.

Women have the possibility of producing a limited number of viable offspring. Men can produce an number of offspring that is limited only by the number of females that reject their advances. The best evolutionary strategy for females would be to exercise extreme discretion in choice of mates as far as that is possible (rape overrides female choice) in order to access the most superior genetic donation to her offspring that she can manage.

You ask how one gender can be more promiscuous than another. What if we send an attractive male out to proposition 100 females and an attractive female out to proposition 100 males. Which one will have more sexual encounters? I realize that my experimental design is sadly lacking in detail but I'll let it stand for now. What do you think?

Wed, 12 Jan 2011 17:50:38 UTC | #577273

hungover's Avatar Comment 9 by hungover

Laurie B,

The idea that females are chaste and males are promiscuous is, as far as I know, based on outdated drosophila research which happened to fit with the human view of female sexuality from the 50s....which was probably not natural : ) Of course, there are species where this is the case but generally females are as promiscuous or more promiscuous than males. Numerous species the females will mate with multiple males in order the generate superior offspring through sperm competition or to cause ambiguity with regard to paternity in order to decrease infanticide. Afterall if males are sleeping around they are not doing it on their own.

Wed, 12 Jan 2011 18:11:57 UTC | #577285

Reveille's Avatar Comment 10 by Reveille

I wonder what this competition aspect has to say about human relations. Do you think human society is set up to allow for optimum breeding, (i.e. best genes, healthy competetion)? I tend to think not.

Wed, 12 Jan 2011 18:33:45 UTC | #577295

CarolineMary's Avatar Comment 11 by CarolineMary

I don't know about the promiscuity thing.

I tend to think, (with no real scientific evidence) that women are a bit more selective than men.

So if you send out Johnny Depp to proposition 100 women, he would have a better success rate than Joe Average.

But, I think, Jane Average (propositioning 100 men) would have a better success rate than Joe Average, too.

Wed, 12 Jan 2011 19:03:47 UTC | #577309

LaurieB's Avatar Comment 12 by LaurieB

hungover,

Who said females are chaste. Not me. Human females are not chaste and they are not monogamous either. Agree with the use of this ridiculous idea in the past to establish a false dichotomy of female sexuality (virgin-whore). In Your claim that females are more promiscuous than males, do you mean across all species? Just primates? Please clarify.

Were you thinking of Pan troglodyte chimps? When the females come into fertility they mate with a number of males for that particular time which would set off sperm competition. Does this fit the description of female promiscuity? And how could you claim that those females are as promiscuous or more promiscuous than the males. The females come into fertility infrequently and it seems as though the males are up for action on a moments notice. Even if we consider the Bonobos where there appears to be plenty of non-reproductive sexual activity, could we say that the females are more promiscuous than the males? I have no references to refute this off the top of my head. Actually I've never considered the possibility that this could be so. Do you have anything on this?

Creation of ambiguity in regards to paternity is an interesting topic. Avoidance of infanticide is one good reason and access to the resources of several males would be another.

Granted, males are not sleeping around on their own but that does not imply a one to one ratio.

Wed, 12 Jan 2011 19:07:36 UTC | #577312

LaurieB's Avatar Comment 13 by LaurieB

CarolineMary,

Ha! Totally agree!

Wed, 12 Jan 2011 19:09:48 UTC | #577313

CarolineMary's Avatar Comment 14 by CarolineMary

13 LaurieB Thanks.

I was trying to edit that to add something, but got timed out...

Has it ever been investigated whether promiscuous females tend to go for males perceived as 'better' than their current mate?

Wed, 12 Jan 2011 19:16:06 UTC | #577314

blitz442's Avatar Comment 15 by blitz442

Laurie B

What if we send an attractive male out to proposition 100 females and an attractive female out to proposition 100 males. Which one will have more sexual encounters? I realize that my experimental design is sadly lacking in detail but I'll let it stand for now. What do you think?

I believe that a very similar experiment was conducted some years ago on a college campus. If memory serves, the attractive male(s) met with a success rate of less than 5%, while the attractive female(s) not only met with a much greater success rate (approaching 70%), but were asked by many of the eager boys she propositioned how long they would have to wait.

Suffice to say, the difference in response was "statistically significant", and, as you imply, hopefully not surprising to any adult with a clue.

Edit:

A quick look on google, some studies were done and showed that while a girl might go on a date with a strange guy (single guys take note, the chances are about 50/50), she ain't going to right back to his apartment and certainly not to right to the sack. Now a guy being propositioned by a hot girl.....

Hi, would you like to have sex with me?

Wed, 12 Jan 2011 19:33:01 UTC | #577321

root2squared's Avatar Comment 16 by root2squared

I believe that a very similar experiment was conducted some years ago on a college campus. If memory serves, the attractive male(s) met with a success rate of less than 5%, while the attractive female(s) not only met with a much greater success rate (approaching 70%), but were asked by many of the eager boys she propositioned how long they would have to wait.

Before I read that, I guessed the %s as 95 and 10-30 depending on other attributes of the male. A million dollars or fame would make average Joe much more attractive, but not help average Jane much. Eg. Oprah vs Hefner.

In general, biologically, I think men are polygamous, while women are polygamous only when accompanied with hypergamy, though social trends can override this.

Wed, 12 Jan 2011 20:48:45 UTC | #577346

Dave H's Avatar Comment 17 by Dave H

I half expected my company web filter to block that picture. Just as well there's not a video.

Wed, 12 Jan 2011 21:07:04 UTC | #577350

crookedshoes's Avatar Comment 18 by crookedshoes

LaurieB,

Yes, but who then is more promiscuous? The woman who would have 100 sex partners or the men who would have sex with someone who would have 100 sex partners?

I'd never have sex with a woman who had just had sex with someone else. Wouldn't do it.

So, these two go out and we think we know the outcome (guys scores some percentage of the time / girl more often). WHat does this say about 1. the individual "going out" and the number of partners the could "glean" 2. the 100 men's promiscuity and the 100 women's?

Also, I work with someone that is a very good looking man. I mean he was christmas shopping and went into an Abercrombie and Fitch and one of the employees approached him and offered him 1000 dollars to stand in the store all day. He routinely has women approach and proposition him, and follow through. It is unbelievable.

I think women are more "free" to tell the truth and be themselves (I AM not that type of girl, how dare you!!!) Is the stuff of old movies. If we had a way to completely remove all other forces (social issues, acceptance, repercussions...) I think the results of your thought experiment would be astounding.

Wed, 12 Jan 2011 21:08:23 UTC | #577351

hungover's Avatar Comment 19 by hungover

Comment 12 by LaurieB :

hungover,

Who said females are chaste. Not me. Human females are not chaste and they are not monogamous either. Agree with the use of this ridiculous idea in the past to establish a false dichotomy of female sexuality (virgin-whore). In Your claim that females are more promiscuous than males, do you mean across all species? Just primates? Please clarify.

Were you thinking of Pan troglodyte chimps? When the females come into fertility they mate with a number of males for that particular time which would set off sperm competition. Does this fit the description of female promiscuity? And how could you claim that those females are as promiscuous or more promiscuous than the males. The females come into fertility infrequently and it seems as though the males are up for action on a moments notice. Even if we consider the Bonobos where there appears to be plenty of non-reproductive sexual activity, could we say that the females are more promiscuous than the males? I have no references to refute this off the top of my head. Actually I've never considered the possibility that this could be so. Do you have anything on this?

Creation of ambiguity in regards to paternity is an interesting topic. Avoidance of infanticide is one good reason and access to the resources of several males would be another.

Granted, males are not sleeping around on their own but that does not imply a one to one ratio.

The original article stated "The heterosexual world of animal reproduction is populated primarily by males eager to mate and females more concerned with finding a superior partner". I was under the impression that this is too broad a generalization and based on outdated research tinged with classic 50s-style sexism. I dont mean across all species and nor does the article make this claim. I think to say, as the original article did, that the heterosexual animal generally behaves in this way is inaccurate. I had no particular species in mind. There is clearly a spectrum of sexual behaviour/levels of promiscuity in the animal kingdom and within a species there is clearly variation amongst individuals. In some animals females are bigger whores, some animals males are bigger whores. I'm not sure if there is a broad enough trend either way. Clearly human females are more selective than males but we're not exactly normal when it comes to sex.

I might be way off on this and there is in fact a very broad trend in this direction. I'm basing this opinion on one book that I read on this topic a few years back...so not exactly done a thorough lit review!

Wed, 12 Jan 2011 21:09:43 UTC | #577352

blitz442's Avatar Comment 20 by blitz442

Comment 19 by hungover

The original article stated "The heterosexual world of animal reproduction is populated primarily by males eager to mate and females more concerned with finding a superior partner".

Just use simple logic. Whenever the cost of reproduction is greater for females than for males of a given species, then ......

Wed, 12 Jan 2011 21:24:27 UTC | #577364

LaurieB's Avatar Comment 21 by LaurieB

CarolineMary,

Yes, it's called cuckolding, where although a woman is in a committed relationship she has the opportunity to be inseminated by a male that she consideres to have features that she admires. From her perspective, her offspring would have the genetic contributions that she admired in the other guy while still accessing the resources of the mate. Birds do it too!

Shall we drop the word promiscuous? It has such negative sexist connotations to me. In my mind promiscuous = slut.

I'm familiar with that campus study. A serious criticism being that while young college aged men would be thanking their lucky stars for an offer of no-strings attached sex with an attractive female falling on them out of the blue, that would not be the case with the college aged females. Strange, attractive men who propose anonymous sex will be judged with suspicion I should think. There are certain risks involved here that could override any impulse to access the attractive guy's genetic material such as:

Where is he taking me? To an isolated location? What if I change my mind, will I be raped? Is he a killer? He's attractive alright but would this be worth the price of picking up an STD? What if he proceeds to broadcast the whole sordid affair to the entire campus? A feather in his cap but certainly not in mine. What if after all this risk he ends up being a dud in bed, etc. In short, I believe that even though those women found the guy to be extremely attractive and wanted to have sex with him, they would have second thoughts about saying yes.

I venture to say that most women have been propositioned out of the blue like what is described in that study. I remember thinking that the guys who did that were desperate creeps. When guys approached me like the one in the study I was never surprised, just disgusted really.

Root, I'm with you on the male polygamy but what is hypergamy please?

Wed, 12 Jan 2011 21:24:44 UTC | #577365

green and dying's Avatar Comment 22 by green and dying

Comment 15 by blitz442 :

Edit:

A quick look on google, some studies were done and showed that while a girl might go on a date with a strange guy (single guys take note, the chances are about 50/50), she ain't going to right back to his apartment and certainly not to right to the sack. Now a guy being propositioned by a hot girl....

There are reasons for this that you're probably not taking into account.

Edit: oh, Laurie got there first.

Wed, 12 Jan 2011 21:28:19 UTC | #577367

blitz442's Avatar Comment 23 by blitz442

Comment 21 by LaurieB

In short, I believe that even though those women found the guy to be extremely attractive and wanted to have sex with him, they would have second thoughts about saying yes.

All valid concerns, although some of them are not unique to women (such as concerns with STDs or underperformance in bed). But in at least one study you have to explain why 75% of men answered in the affirmative while not a single woman did. Are all of your explanations adequate?

It seems reasonable to me to propose additional factors. Perhaps women do not get as sexually aroused visually as men do. Perhaps some women desire additional qualities in the opposite sex before getting sexually aroused (such as high status, power, or money).

None of this, by the way, would support the idea that women are less interested in sex than men, overall. What is interesting to me is that we have a very profound gender difference in behavior in this situation, the explanation of which seems amenable to a largely (but not exclusively) Darwinian explanation, rather than something that is a pure artifact of culture and social factors.

Root, I'm with you on the male polygamy but what is hypergamy please?

Marrying up.

Wed, 12 Jan 2011 21:37:46 UTC | #577369

blitz442's Avatar Comment 24 by blitz442

Comment 22 by green and dying

There are reasons for this that you're probably not taking into account.

In this post, I was just citing a finding. As the link shows, the reasons could be many.

Wed, 12 Jan 2011 21:39:45 UTC | #577371

root2squared's Avatar Comment 25 by root2squared

Perhaps some women desire additional qualities in the opposite sex before getting sexually aroused (such as high status, power, or money).

Don't know if this is sound, but:

From The Sunday Times January 18, 2009 Wealthy men give women more orgasms

Wed, 12 Jan 2011 21:54:03 UTC | #577375

green and dying's Avatar Comment 26 by green and dying

Comment 24 by blitz442 :

In this post, I was just citing a finding. As the link shows, the reasons could be many.

Okay. I don't think it's a very useful finding, is all.

Comment 25 by root2squared :

Don't know if this is sound, but:

From The Sunday Times January 18, 2009 Wealthy men give women more orgasms

They're probably more intelligent.

Wed, 12 Jan 2011 22:01:34 UTC | #577378

SoHelpMeReason's Avatar Comment 27 by SoHelpMeReason

Bob Scientist

Worm Sex Investigator.

Science Research Institute

(281) 555-6373

www.himandher.com/xxx

BEST JOB TITLE EVER.

Wed, 12 Jan 2011 22:09:56 UTC | #577382

SoHelpMeReason's Avatar Comment 28 by SoHelpMeReason

(Not actual numbers or website.) (At least I haven't checked.)

(Don't even think about it.)

Wed, 12 Jan 2011 22:10:51 UTC | #577383

LaurieB's Avatar Comment 29 by LaurieB

Crooked,

Your question doesn't make sense. You have no reliable access to the number of sex partners a female has had. Like House says, people lie and women have good reason to lie about this question.

You wouldn't have sex with a woman who just had sex with someone else? What makes you think she would inform you of the fact? You wouldn't know unless you were in a situation where you observed prior act and if that was the case then I tend to think you knew what you were getting into, literally. So are you saying that if you had the opportunity to participate in a three way that you would say no thanks?

hehe! Very funny about the Abercrombie guy. That women proposition him and follow through doesn't surprise me in the least. It's the circumstances that matter in this case.

Legality and availability of birth control for women has had an effect on female sexual behavior of course. Women don't have to worry that every copulation could result in a pregnancy. But these medical and legal advances are very recent in our history. I remind young women all the time that The Pill became legal here in the States in 1960 and abortion in 1973, Roe V Wade. What I've been talking about previously should be considered in an evolutionary context, not just what you observed happening at the local pub last Friday night.

Wed, 12 Jan 2011 22:12:19 UTC | #577384

Nunbeliever's Avatar Comment 30 by Nunbeliever

Nah, I actually thought this artile was about something else. What a misleading headline ;-)

Wed, 12 Jan 2011 22:12:51 UTC | #577385