Women are not meant by nature to be faithful

[dixonmassey]

Otherwise, why would spermatozoids be "programmed" to search and destroy other men's spermatozoids in woman's uterus? They always expect to face enemies in the game of life Does it mean that current concept of family is against nature designs? Seems that a woman pleasured by many men while getting pregnant is much closer to the natural state of things. I bet offsprings would be healthier too

 

[valich]

As far as I know, all sperm actively try to impregnate the female egg, not destroy other sperm? What is your source of information here?

In any case, you are making a huge quantum leap by extrapolating the process of impregnation to "the current concept of family" as possibly being against "nature designs." What makes you think there is a design in Nature? What makes you think that life is "a game of life"? What makes you think that a woman's pleasure, or any pleasure, is closer to the "natural state of things"? What makes you think that the "offspring would be healthier too"?

Wow! You posted three short confused questions that actually could make up about ten different threads. You need to focus more and be more logical and rational in your thoughts?

 

[dixonmassey]

As far as I know, all sperm actively try to impregnate the female egg, not destroy other sperm? What is your source of information here?

Is killing genetic competitors is not a part of actively trying to impregnate the female? I've read a few things on fertilization mentioning "killer sperm" hunting strangers in a uterus. Fertilization is one big massacre, which makes one think about what "choosing life" does involve . Here a result of a fast google search.
if the woman has been with another man in the recent past, there may still be other sperm from another man lurking in her uterus. Some of these sperm from the other man are special hunting and killing sperm whose sole purpose is to wait for another mans sperm to arrive and kill as many as possible to limit their chance of reaching the egg.

In any case, you are making a huge quantum leap by extrapolating the process of impregnation to "the current concept of family" as possibly being against "nature designs."

Family is to a large extent a cultural institution. But let's assume humans are just like any other beast. Then, killer sperm (if it does exist) couldn't evolve, just for the heck of it. Obviously, men having a few millions of killer spermatozoids ready were more likely to leave offsprings behind. Using kindergarden level reasoning, I assume that monogamous relationships, officially praised in the current culture, were not the kind of relationships our ancient monkey-like ancestors practiced. Making reverse leap of logic, I assume that current concept of family ideal (single partner from craddle to grave) is not the kind of relationships where the killer sperm is needed.

What makes you think there is a design in Nature?

Design is a word with broad meaning, it does not necesseraly imply creationism. It could be shaping of something (willing to survive no matter what) by the outside environment.

What makes you think that life is "a game of life"?

I do think that life is a game of large numbers. The word "game" just implies uncertainty and chance.

What makes you think that a woman's pleasure, or any pleasure, is closer to the "natural state of things"?

Well, I do think that if copulation caused intense pain, like pulling out a few teeth without an anesthetic, porn would not be #1 content (by traffic) on the internet. I'm not sure what is more "natural" suffering or pleasure, but pleasure is definitely natural, in the sense that certain actions/things makes us (and not only us) feel good. Ever watched a cow who's got the kind of grass it likes? Pleasure is written all over her

What makes you think that the "offspring would be healthier too"?

Since, fertilization by a single man is a mega war in which billions of spermatozoids die so one could win, my guess that few tens of millions of "invadors" would make fertilization war more intense. Winner of such a war should be "stronger" and helthier, so I think.

 

[valich]

I'm very sorry, but I do not answer postings line-by-line simply because I just do not have the time - unless perhaps it is important.

Okay. I did a quick search on Google using "sperm kill each other by," then sperm kill each other," then finally by using "sperm kill" I came up with only one source:

"ABNORMAL sperm turn suicidal in order to prevent harmful mutations being passed to offspring, a new report says." http://www.google.com/search?hl=en&lr=&q="sperm+kill"

I did not bother to read this article as it seems very questionable to begin with from the capitalized enunciation of the first word and the ending stating "a new report says." When trying to be scientific, these are clues that you might want to look for before wasting your time, but of course you can follow the source and see what it says.

Again, you state:

"if the woman has been with another man in the recent past, there may still be other sperm from another man lurking in her uterus. Some of these sperm from the other man are special hunting and killing sperm whose sole purpose is to wait for another mans sperm to arrive and kill as many as possible to limit their chance of reaching the egg."

But you give no source or scientific research study of this?

Then you talk about "killer sperm (if it does exist)."

Where are you getting these ideas???

Monogamous vs. polygamous species vary and this subject really should be posted on a separate Biology forum thread. But it is a good subject to discuss.

I did not and am not implying that the word "design" should be associated with creationism. Still, the concept assumes a preconceived plan.

I agree. Life is a game in that it implies uncertainty and chance. And sometimes viewing life as "just a game" adds more enjoyment to it as it often takes away some of the unnecessary seriousness of it that leads to a lot of stress and anxiety.

Copulation. Again, you're drifting way off track here. I never suggested that it cause any pain, although some and many - not all - women do realize that it may cause them more pain in the form of getting pregnant and dealing with that if they don't feel they are ready for it, as is often the case - again, different subject. Yes, both men and women usually enjoy sex.

Fertilization both on the micro spermatozoid scale and the macro societal-cultural scale are equally intense.

 

[redarmy11]

Whereas sperm+competitors brings up about 2 million hits. The top ones seem relevant.

http://www.google.co.uk/search?as_q...as_dt=i&as_sitesearch=&as_rights=&safe=images

Actually, reading further, maybe not. So I tried "rival sperm" and came across this:

http://www.newscientist.com/article...lipedes-make-short-work-of-rivals-sperm-.html

African male millipedes scurrying around the bush go to great lengths to make sure it is their sperm which fertilises the female's eggs - they scoop out sperm from previous matings and insert their own.

And this:

The penis is a competitive beast
http://news.bbc.co.uk/2/hi/health/3128753.stm


Scientists believe the shape of the penis may have evolved to help men remove the semen of love rivals during sex.
Tests led a team of US researchers, headed by Professor Gordon Gallup, to conclude that the penis acts as a "semen displacement device" and its shape has evolved in part to displace another man's semen.

The team from the State University of New York believe the thrust of the penis during sex may help to clear a woman's reproductive system of a previous lover's semen.

Nothing about killing rival sperm as such, but plenty to suggest that we've evolved a number of techniques for competing with reproductive rivals. It seems fair to conclude that women can't keep it in their pants.

 

[spuriousmonkey]

The matter is a bit clouded I'm afraid by the complexity of the issue. In humans there is more than one viable strategy.

It pays off to be faithful. And it also pays off not to be faithful.

Moreover faithfulness can be also temporary. In some species it lasts a lifetime, but in humans a shorter monogamous period seems more natural. The most crucial period being the first two years or so.

Moreover sex can be used to cement a stable relationship between two people and at the same time sex can be sought outside the relationship to increase fitness. For the woman it doesn't really matter as such which man she reproduces with. She will pass on 50% of her genes in any case. If you always have sex with the same man you are betting on one horse. If it is a good horse this is quite ok, but you could also spread the risk by also taking a bet on another horse. If it is done behind the back of the steady partner and she gets away with it she can in theory increase her fitness. However, should the deceit be exposed she runs the risk of losing a stable family unit. Nowadays this is not so bad as it once was, but it is often still a situation that should be avoided.

There is no easy answer to this problem.

Naturally if men are not meant to be faithful it automatically means that women are not meant to be faithful either. Otherwise the 'unfaithfull' strategy in men would be pointless since there are no women to have sex with. They would all be tied up in fixed relationships.

And so there are two sides to the story to complicate matters.

 

[2inquisitive]

dixonmassey,

Otherwise, why would spermatozoids be "programmed" to search and destroy other men's spermatozoids in woman's uterus?

This is just an Urban Legend, there are no 'killer sperm'.
dixonmassey,

if the woman has been with another man in the recent past, there may still be other sperm from another man lurking in her uterus. Some of these sperm from the other man are special hunting and killing sperm whose sole purpose is to wait for another mans sperm to arrive and kill as many as possible to limit their chance of reaching the egg.

Why didn't you post the link? Could it be because it was a quote from some kid on a forum? Look in post by 'garrye', no. (6).
http://72.14.209.104/search?hl=en&q....com/question/index?qid=20061005161518AAqNcD5

 

[redarmy11]

These eggheads also think the thread starter is talking rubbish:

No evidence for killer sperm or other selective interactions between human spermatozoa in ejaculates of different males in vitro

http://eprints.whiterose.ac.uk/archive/00000197/

This study examines one of the possible mechanisms of sperm competition, i.e. the kamikaze sperm hypothesis. This hypothesis states that sperm from different males interact to incapacitate each other in a variety of ways. We used ejaculates from human donors to compare mixes of semen in vitro from the same or different males. We measured the following parameters: (i) the degree of sperm aggregation, velocity and proportion of morphologically normal sperm after 1 and 3 h incubation in undiluted semen samples, (ii) the proportion of viable sperm plus the same parameters as in (i) in 'swim-up' sperm suspensions after 1 and 3 h incubation, (iii) the degree of self and non-self sperm aggregation using fluorescent dyes to distinguish the sperm of different males, and (iv) the extent of sperm capacitation and acrosome-reacted sperm in mixtures of sperm from the same and different males. We observed very few significant changes in sperm aggregation or performance in mixtures of sperm from different males compared with mixtures from the same male and none that were consistent with previously reported findings. The incapacitation of rival sperm therefore seems an unlikely mechanism of sperm competition in humans.

Here's more on the 'Kamikaze sperm' hypothesis - first proposed by Baker and Bellis, and widely criticised:

http://psyed.org/r/nn/nnd/s/sxd/kamikaze.html

In 1988 Baker and Bellis first proposed the "Kamikaze sperm" hypothesis (Baker and Bellis 1988; Baker and Bellis 1989; Baker and Bellis 1993; Baker and Bellis 1993) . This was an extention of Parker's ideas on the role of plugs and blocking agents in sperm competition (Parker 1970; Parker 1984; Parker and Begon 1993) . In essence, they envisaged two types of human sperm, "egg-getters" and "kamikaze" forms specialized either to block competitors or to roam around the female tract seeking to destroy competitors (using acrosomal enzymes?). This was fleshed out in a highly entertaining and best-selling book, "Human Sperm Competition. Copulation, Masturbation and Infidelity" (Baker and Bellis 1995) , and has been widely publicised including a TV documentary, "Sperm Wars". Roger Short has a devastating review from the 47th newsletter of the European Sociobiological Society

The book actually provides a wonderful read, even though many of its conclusions are pretty wild and have not been published in peer-reviewed journals (sperm heads changing shape in mixed ejaculates, for example). My major problem is that they produce a most complicated explanation for what may be a straightforward problem and there is no convincing direct evidence for adaptive roles for the various morphs (Gomendio and Roldan 1991; Gomendio and Roldan 1993) . If you accept that humans produce abnormal sperm simply because we are not very fertile and the quality control mechanisms in the testis are deficient, then there is no need for an obsessive need to find an "adaptive" explanation for every aspect of sperm biology. In fact Occam's razor demands that we should always prefer the simplest explanation even if it doesn't grab the popular imagination.

Harcourt (1991) has shown that the numbers of abnormal sperm in mammals -- and especially in Primates -- do not correlate with mating pattern. If the "kamikaze sperm" hypothesis were correct one would expect to see more abnormal forms in species with high intensity of sperm competition, whereas if anything the reverse is true. Baker and Bellis responded by suggesting that variation is likely to be greater in species that have cryptic estrus (like humans) but of course this doesn't explain high levels of pleiomorphism in sperm of gorillas where the chances of sperm competition are pretty minimal, nor in a diverse range of species ranging from thoroughbred stallions (cryptic estrus in mares?) to koalas, cheetahs and other big cats (Cummins 1990) .

I suspect that Baker and Bellis have fallen into the Panglossian trap of assuming that every aspect of sperm biology is adaptive. Indeed abnormal sperm can't even be considered to be exaptations (features that may enhance fitness but that were not designed by natural selection for their current role) (Gould and Vrba 1982) because they do not normally participate in fertilization. While abnormally shaped sperm (in mice) can generate normal embryos when microinjected into oocytes (Burruel, Yanagimachi et al. 1996) , in normal circumstances barriers in the reproductive tract such as cervical mucus and the zona pellucida actively select against abnormal forms (Katz, Morales et al. 1990; Liu and Baker 1994) and are probably the major selective mechanisms for defining the heredity of sperm form (Bedford 1991) .

Kamikaze sperm? I'm not convinced. I'm happy to post any comments or rebuttals, though.

 

[Kumar]

Women are not meant by nature to be faithful?

Do you mean that faithful in one child bearing time or for whole life?

 

[valich]

Dixonmassey apparently has a lot of warped ideas about women, and certainly also about sperm. The scientific posts above all go to show that there is no such thing as "killer sperm," but then to use this fraudulent idea to then suggest that "Women are not meant by nature to be faithful" is utterly absurd. I suggest that we not fuel the flames of further absurdity by asking any further questions as to what he means by all this.

As an interesting side note - and this really has nothing to do with the ridiculous title and initial posting of this thread - we had a guy in a colleague's biology department who decided to examine a sample of sperm one night (don't ask where he got it from!?). He said that he was amazed at the amount of sperm that had two and even three flagellum (tails) that the sperm concentration had. This would be evidence for mutations, and possibly for increased competitiveness.

 

[Kumar]

Dixonmassey apparently has a lot of warped ideas about women, and certainly also about sperm. The scientific posts above all go to show that there is no such thing as "killer sperm," but then to use this fraudulent idea to then suggest that "Women are not meant by nature to be faithful" is utterly absurd. I suggest that we not fuel the flames of further absurdity by asking any further questions as to what he means by all this.

We can understand this aspect in view nature's rules, social and moral rules, diseases(STDS), incompactibilities etc. differently.

Whether females of most of other species are weaker than males--naturally?

As an interesting side note - and this really has nothing to do with the ridiculous title and initial posting of this thread - we had a guy in a colleague's biology department who decided to examine a sample of sperm one night (don't ask where he got it from!?). He said that he was amazed at the amount of sperm that had two and even three flagellum (tails) that the sperm concentration had. This would be evidence for mutations, and possibly for increased competitiveness.

Interesting, As such, probably we may have more legs in future?

 

[valich]

We can understand this aspect in view nature's rules, social and moral rules, diseases(STDS), incompactibilities etc. differently.

Whether females of most of other species are weaker than males--naturally?

Interesting, As such, probably we may have more legs in future?

I do not understand the relevance of your reply. Nature has no rules. Females are muscularly weaker than men, but they are not weaker than men. Both sexes are allocated an equal amount of energy potential but a female's metabolic functions divert more energy into reproductive organs and systems, and the reproductives processes than that of men. I think this may be new news for you that you need to consider before suggesting that females are weaker than males. I don't think you know very much about the great diversity of metabolic processes in our diversity of species.

 

[Kumar]

I do not understand the relevance of your reply. Nature has no rules.

Nature's rule may quite simple, just initiation towards "Nature's balance"-- a balance of all beings and things in perfect hormony to each other--somewhat homeostatis.

Females are muscularly weaker than men, but they are not weaker than men. Both sexes are allocated an equal amount of energy potential but a female's metabolic functions divert more energy into reproductive organs and systems, and the reproductives processes than that of men.

Is it common in other species esp. in those living in natural environment without infuluence of modern type of social environment. Whether a lioness is weaker in physical strength then a lion(both living in natural environment to them) of same age? I just want to understand, whether variations in physical and mental strength(evolved, inherited or aquired) in males and females in humans(living in society) is natural or manmade?

[quoute] I think this may be new news for you that you need to consider before suggesting that females are weaker than males. I don't think you know very much about the great diversity of metabolic processes in our diversity of species.[/QUOTE]

In common, can a common untrained woman fight with many of similar age physically and win?

Whether previous or current diversities were/are Manmade or natural?

 

[dixonmassey]

Dixonmassey apparently has a lot of warped ideas about women, and certainly also about sperm. The scientific posts above all go to show that there is no such thing as "killer sperm," but then to use this fraudulent idea to then suggest that "Women are not meant by nature to be faithful" is utterly absurd. I suggest that we not fuel the flames of further absurdity by asking any further questions as to what he means by all this.

In animal kingdom there are multiple examples of males making sure that's namely their sperm is going to be a winner. Granted, the examples I'm aware of do not involve the "killer sperm", but the trend exists. As far I understand, "killer sperm" is not a mainstream science (it could be quack science too). Then why not to study it more? Tonnes of $ are spent on much sillier projects. To refute the idea just because it does not fit your views of women is not right.

From a pure biological view (let's assume that women care only about making and growing the most healthiest, fittest children possible), human femails should choose the healthiest etc. sperm donor + the most reliable partner to grow kids. It's obvious, that those two individuals would not be the same in most of the cases.

As an interesting side note - and this really has nothing to do with the ridiculous title and initial posting of this thread - we had a guy in a colleague's biology department who decided to examine a sample of sperm one night (don't ask where he got it from!?). He said that he was amazed at the amount of sperm that had two and even three flagellum (tails) that the sperm concentration had. This would be evidence for mutations, and possibly for increased competitiveness.

You accept the idea of the three-tailed sperm, but you refute the idea of the chemical-biological fighter sperm upfront? Maybe if you join "forces" with your collegeague, you'll see even more interesting things under microscope.

 

[TimeTraveler]

Otherwise, why would spermatozoids be "programmed" to search and destroy other men's spermatozoids in woman's uterus? They always expect to face enemies in the game of life Does it mean that current concept of family is against nature designs? Seems that a woman pleasured by many men while getting pregnant is much closer to the natural state of things. I bet offsprings would be healthier too

Humans are not meant, by nature to be monogamous. Humans are naturally polygamous, only some humans are designed for monogamy. It's not gender, it's genes, some humans can't do monogamy, so what? We shouldnt expect everyone to do monogamy anyway.