# When did we find out that sex = baby? **URL:** \ **Category:** Factual Questions\ **Created:** [May 11, 2006, 3:55am UTC](https://boards.straightdope.com/t/when-did-we-find-out-that-sex-baby/356329 "2006-05-11T03:55:26Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Mighty\_Girl](https://avatars.discourse-cdn.com/v4/letter/m/7bcc69/32.png) [@Mighty\_Girl](https://boards.straightdope.com/u/Mighty_Girl)\ **Post date:** [May 11, 2006, 3:55am UTC](https://boards.straightdope.com/t/when-did-we-find-out-that-sex-baby/356329/1 "2006-05-11T03:55:26Z")
Not ‘we’ as each one of us, but ‘we’ as in humans. Years ago in the university I read an anthropology book that mentioned a certain primitive society, still existing at the time the book was written, that believed that women got pregnant because spirits living in the ocean entered their bodies. If a woman got pregnant during her husband’s long absence nobody thought anything of it. I am not sure but I think that it was a matriarchal society. Anyone knows which tribe it is and if they still hold this belief? Anyways, that’s not my main question, the question is ‘how and when did we make the connection that sex = babies?’. And if it is so obvious that the vast majority of societies discovered it early on, how comes these people have’t figured it out yet. ---
**Author:** ![Civil\_Guy](https://avatars.discourse-cdn.com/v4/letter/c/d78d45/32.png) [@Civil\_Guy](https://boards.straightdope.com/u/Civil_Guy)\ **Post date:** [May 11, 2006, 4:14am UTC](https://boards.straightdope.com/t/when-did-we-find-out-that-sex-baby/356329/2 "2006-05-11T04:14:38Z")
Someone who knows what they’re talking about will be along shortly, I hope. I read up on this once, sheer curiosity - I think the book was by Panati, concerning general trivia on sex. I don’t remember the exact time line. As with many matters of human knowledge, different things were figured out at different times. Anyone who grew up on a farm would figure out that it takes a visit by a bull to give a cow calves. Men are pretty clueless, but you’d think that women would have figured out pretty early that there’s some connection between having sex with a man and getting preggers. Still, it took a while for anyone to actually see the sperm in semen - small swimmers, they are - though IIRC it could even have been VanLeuwenhook himself to first see something odd in his own spunk (someone had to be first, but whoever it was had a strange sense of curiosity, for sure). Anhow, it would surely have taken a while longer for anyone to observe sperm fertilizing an egg, then observing that the fertilized egg took off to produce an embryo. Probably happened first with fish or frog eggs, I speculate / possibly recall. ---
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [May 11, 2006, 6:15am UTC](https://boards.straightdope.com/t/when-did-we-find-out-that-sex-baby/356329/3 "2006-05-11T06:15:17Z")
> [@Civil Guy](#): > > Still, it took a while for anyone to actually see the sperm in semen - small swimmers, they are - though IIRC it could even have been VanLeuwenhook himself Sperm are very small, and I believe that his early microscopes would not have provided enough magnification for him to actually observed sperm swimming. As I recall it takes a magnification of 500 to 1000 times to see sperm clearly. There is also the problem that in those types of microscopes, the light required to see at such magnification levels tends to kill the sperm. So he wouldn’t have seen them ‘swimming’. As for the OP, actual scientific proof was given only about 180 years ago: “The elementary fact of fertilization, namely, that a sperm rather than the seminal fluid is required to initiate development of the ovum, was discovered by J.L.Prevost and J.B.Dumas in 1824.”\* Of course, it was ‘known’ (just unproven) long before that – probably since prehistoric humans started breeding animals. - Cite: [http://scienceclassics.nas.edu/moore/chap02.html](http://scienceclassics.nas.edu/moore/chap02.html) ---
**Author:** ![Szlater](https://avatars.discourse-cdn.com/v4/letter/s/90ced4/32.png) [@Szlater](https://boards.straightdope.com/u/Szlater)\ **Post date:** [May 11, 2006, 10:20am UTC](https://boards.straightdope.com/t/when-did-we-find-out-that-sex-baby/356329/4 "2006-05-11T10:20:35Z")
> [@t-bonham@scc.net](#): > > Sperm are very small, and I believe that his early microscopes would not have provided enough magnification for him to actually observed sperm swimming. As I recall it takes a magnification of 500 to 1000 times to see sperm clearly. > > There is also the problem that in those types of microscopes, the light required to see at such magnification levels tends to kill the sperm. So he wouldn’t have seen them ‘swimming’. Antonie van Leeuwenhoek most definately did observe living, swimming spermatozoa. In 1676 he was the first person to describe in detail bacteria, although he used the term ‘animalcules’. It’s thought that he became interested in microscopy after his only visit to London in 1668 during which he probably saw a copy of Hooke’s ‘Micrographia’. In 1667 he was the first person to describe in detail bacteria. > [@Van Leeuwenhoek](#): > > ‘[They] were incredibly small, nay so small, in my sight, that I judged that even if 100 of these very wee animals lay stretched out one against another, they could not reach to the length of a grain of coarse Sand’. In 1677, after looking at a great many other things he turned his attention to semen. Apparently his first subject was a man with an STI, and he initially believed the sperm to be the cause of the disease. However, over the next 4 decades he observed sperm from many different animals, from molluscs to mammals, fish and birds. Eventually came up with a revolutionary theory, that the egg is fertilised when a sperm penetrates it. So… he really did see, and was the first to describe, sperm. He was also the person who put two and two together. ---
**Author:** ![Szlater](https://avatars.discourse-cdn.com/v4/letter/s/90ced4/32.png) [@Szlater](https://boards.straightdope.com/u/Szlater)\ **Post date:** [May 11, 2006, 10:22am UTC](https://boards.straightdope.com/t/when-did-we-find-out-that-sex-baby/356329/5 "2006-05-11T10:22:59Z")
Gah!.. errors ahoy! That’ll teach me to proofread! A v L described bacteria in 1676 He described sperm in 1677 Sorry 'bout that! ---
**Author:** ![blinkingblinking](https://avatars.discourse-cdn.com/v4/letter/b/ea5d25/32.png) [@blinkingblinking](https://boards.straightdope.com/u/blinkingblinking)\ **Post date:** [May 11, 2006, 11:06am UTC](https://boards.straightdope.com/t/when-did-we-find-out-that-sex-baby/356329/6 "2006-05-11T11:06:30Z")
> [@Mighty\_Girl](#): > > Not ‘we’ as each one of us, but ‘we’ as in humans. > > Years ago in the university I read an anthropology book that mentioned a certain primitive society, still existing at the time the book was written, that believed that women got pregnant because spirits living in the ocean entered their bodies. If a woman got pregnant during her husband’s long absence nobody thought anything of it. I am not sure but I think that it was a matriarchal society. Anyone knows which tribe it is and if they still hold this belief? > > Anyways, that’s not my main question, the question is ‘how and when did we make the connection that sex = babies?’. And if it is so obvious that the vast majority of societies discovered it early on, how comes these people have’t figured it out yet. I am not sure if it is exactly the ssociety you are talking about but here goes. I read about a society that does not think that sexual intercourse is the determining thing for the woman getting pregnant. They do not say a woman can get pregnant without having sexual intercourse. Just that there is a more important factor. When asked about this they, fairly reasonably pointed out that some married couples had had sex thousands of times and only had one kid. Thus they reasoned it must be some other factor that got the woman pregnant that one special time. What was that factor? Some ‘supernatural’ occurrence. ---
**Author:** ![Arjuna34](https://avatars.discourse-cdn.com/v4/letter/a/eb8c5e/32.png) [@Arjuna34](https://boards.straightdope.com/u/Arjuna34)\ **Post date:** [May 11, 2006, 12:22pm UTC](https://boards.straightdope.com/t/when-did-we-find-out-that-sex-baby/356329/7 "2006-05-11T12:22:08Z")
The master speaks: [When did mankind figure out that SEX = BABIES?](http://www.straightdope.com/classics/a3_210.html) ---
**Author:** ![Malacandra](https://avatars.discourse-cdn.com/v4/letter/m/45deac/32.png) [@Malacandra](https://boards.straightdope.com/u/Malacandra)\ **Post date:** [May 11, 2006, 1:18pm UTC](https://boards.straightdope.com/t/when-did-we-find-out-that-sex-baby/356329/8 "2006-05-11T13:18:13Z")
> [@Civil Guy](#): > > Someone who knows what they’re talking about will be along shortly, I hope. I read up on this once, sheer curiosity - I think the book was by Panati, concerning general trivia on sex. > > I don’t remember the exact time line. As with many matters of human knowledge, different things were figured out at different times. > > Anyone who grew up on a farm would figure out that it takes a visit by a bull to give a cow calves. **Men are pretty clueless** , but you’d think that women would have figured out pretty early that there’s some connection between having sex with a man and getting preggers. > > Still, it took a while for anyone to actually see the sperm in semen - small swimmers, they are - though IIRC it could even have been VanLeuwenhook himself to first see something odd in his own spunk (someone had to be first, but whoever it was had a strange sense of curiosity, for sure). > > Anhow, it would surely have taken a while longer for anyone to observe sperm fertilizing an egg, then observing that the fertilized egg took off to produce an embryo. Probably happened first with fish or frog eggs, I speculate / possibly recall. :rolleyes: Figure that a lot of early herders would have been men, and noticed that the bulls, rams and billies got awfully interested in their females in a certain season of the year, and shortly afterwards the females have big bellies, and after that the calves, lambs and kids. And thence the connection. Larry Gonick’s _Cartoon History of the Universe_ dates this to nomadic-herder times, and links it to a change in status of women. Only a cartoonist, but his bibliography is extensive. ---
**Author:** ![Spectre\_of\_Pithecanthropus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/spectre_of_pithecanthropus/32/12343_2.png) [@Spectre\_of\_Pithecanthropus](https://boards.straightdope.com/u/Spectre_of_Pithecanthropus)\ **Post date:** [May 11, 2006, 1:43pm UTC](https://boards.straightdope.com/t/when-did-we-find-out-that-sex-baby/356329/9 "2006-05-11T13:43:44Z")
> [@Civil Guy](#): > > Anyone who grew up on a farm would figure out that it takes a visit by a bull to give a cow calves. Remember, though, that humans are _traditionally_ considered as being apart from “animals”. “Humans are animals”, or in older times, “Man is an animal”, is something that we usually learn from books or in a setting of formal instruction. Given the exceptionalism with which the human animal was viewed in primitive times, I’m not sure people would have realized that bull:cow:👨woman in terms of producing offspring. ---
**Author:** ![even\_sven](https://avatars.discourse-cdn.com/v4/letter/e/dfb087/32.png) [@even\_sven](https://boards.straightdope.com/u/even_sven)\ **Post date:** [May 11, 2006, 4:06pm UTC](https://boards.straightdope.com/t/when-did-we-find-out-that-sex-baby/356329/10 "2006-05-11T16:06:30Z")
Let’s also not forget that a fertile woman in a traditional society could expect to be pregnant more or less continually in her adult life, further obscureing the specific cause. ---
**Author:** ![Sattua](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sattua/32/11906_2.png) [@Sattua](https://boards.straightdope.com/u/Sattua)\ **Post date:** [May 11, 2006, 4:46pm UTC](https://boards.straightdope.com/t/when-did-we-find-out-that-sex-baby/356329/11 "2006-05-11T16:46:01Z")
On the other hand, in one of the history courses I took (and I SO don’t have a cite… sorry, people) the professor claimed that in hunter-gatherer societies, a woman’s children tend to be 3-4 years apart. Whether it’s because of low body fat = no menses = no babies while she’s nursing, or just because new mothers often don’t feel like boinking, I don’t know. But apparently (again, no cite, me bad) it isn’t necessarily standard for a woman to be constantly pregnant. ---
**Author:** ![Spectre\_of\_Pithecanthropus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/spectre_of_pithecanthropus/32/12343_2.png) [@Spectre\_of\_Pithecanthropus](https://boards.straightdope.com/u/Spectre_of_Pithecanthropus)\ **Post date:** [May 11, 2006, 4:54pm UTC](https://boards.straightdope.com/t/when-did-we-find-out-that-sex-baby/356329/12 "2006-05-11T16:54:32Z")
> [@Sattua](#): > > On the other hand, in one of the history courses I took (and I SO don’t have a cite… sorry, people) the professor claimed that in hunter-gatherer societies, a woman’s children tend to be 3-4 years apart. Whether it’s because of low body fat = no menses = no babies while she’s nursing, or just because new mothers often don’t feel like boinking, I don’t know. But apparently (again, no cite, me bad) it isn’t necessarily standard for a woman to be constantly pregnant. I’ve usually heard nursing as the primary reason this happens. I don’t know if this is still done in Japan today, but my parents met there in the 1950s and have told me that, on the train, you would see children nursing who were big enough to stand and reach their mother’s breasts as they sat–which I assume must mean the kids were around 3 or 4 y.o. ---
**Author:** ![WhyNot](https://avatars.discourse-cdn.com/v4/letter/w/c77e96/32.png) [@WhyNot](https://boards.straightdope.com/u/WhyNot)\ **Post date:** [May 11, 2006, 5:07pm UTC](https://boards.straightdope.com/t/when-did-we-find-out-that-sex-baby/356329/13 "2006-05-11T17:07:33Z")
> [@Sattua](#): > > On the other hand, in one of the history courses I took (and I SO don’t have a cite… sorry, people) the professor claimed that in hunter-gatherer societies, a woman’s children tend to be 3-4 years apart. Whether it’s because of low body fat = no menses = no babies while she’s nursing, or just because new mothers often don’t feel like boinking, I don’t know. But apparently (again, no cite, me bad) it isn’t necessarily standard for a woman to be constantly pregnant. And this would fuzzify the issue further, wouldn’t it? There’s two to three years of sex without a baby happening. That makes the connection more tenuous, I’d think. ---
**Author:** ![Acsenray](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/acsenray/32/4519_2.png) [@Acsenray](https://boards.straightdope.com/u/Acsenray)\ **Post date:** [May 11, 2006, 5:23pm UTC](https://boards.straightdope.com/t/when-did-we-find-out-that-sex-baby/356329/14 "2006-05-11T17:23:33Z")
> [@Mighty\_Girl](#): > > Not ‘we’ as each one of us, but ‘we’ as in humans. > > Years ago in the university I read an anthropology book that mentioned a certain primitive society, still existing at the time the book was written, that believed that women got pregnant because spirits living in the ocean entered their bodies. If a woman got pregnant during her husband’s long absence nobody thought anything of it. I am not sure but I think that it was a matriarchal society. Anyone knows which tribe it is and if they still hold this belief? > > Anyways, that’s not my main question, the question is ‘how and when did we make the connection that sex = babies?’. And if it is so obvious that the vast majority of societies discovered it early on, how comes these people have’t figured it out yet. I just want to confirm that I read this same story as an undergraduate, but like the OP I don’t remember the details clearly. I seem to recall that it was on some Pacific island where the people spend a lot of time in the surf (harvesting sea cucumbers and such, perhaps?). The researcher tried to explain to some of the people that it was sexual intercourse that resulted in pregnancy, but he was not very successful in convincing them. The killer argument came from one man who said something like “I was gone for almost a year and my wife had a baby. That proves that sex is not the cause of pregnancy.” Apparently, the researcher didn’t think it wise to accuse the man’s wife of sexual infidelity. ---
**Author:** ![Mighty\_Girl](https://avatars.discourse-cdn.com/v4/letter/m/7bcc69/32.png) [@Mighty\_Girl](https://boards.straightdope.com/u/Mighty_Girl)\ **Post date:** [May 11, 2006, 6:47pm UTC](https://boards.straightdope.com/t/when-did-we-find-out-that-sex-baby/356329/15 "2006-05-11T18:47:50Z")
> [@acsenray](#): > > The killer argument came from one man who said something like “I was gone for almost a year and my wife had a baby. That proves that sex is not the cause of pregnancy.” Yep, sounds like the same book. ---
**Author:** ![bup](https://avatars.discourse-cdn.com/v4/letter/b/6bbea6/32.png) [@bup](https://boards.straightdope.com/u/bup)\ **Post date:** [May 11, 2006, 6:59pm UTC](https://boards.straightdope.com/t/when-did-we-find-out-that-sex-baby/356329/16 "2006-05-11T18:59:00Z")
[quote] Remember, though, that humans are traditionally considered as being apart from “animals”. “Humans are animals”, or in older times, “Man is an animal”, is something that we usually learn from books or in a setting of formal instruction. Given the exceptionalism with which the human animal was viewed in primitive times, I’m not sure people would have realized that bull:cow:👨woman in terms of producing offspring.Remember, also, that semen has been euphemistically called “seed” since ancient times. They knew. As someone else in this thread mentioned in passing, it’s hard to imagine domestication of animals without understanding of this - you’re trying to get certain traits into offspring, and get rid of others. Dogs were domesticated - 30,000 years ago? ---
**Author:** ![bup](https://avatars.discourse-cdn.com/v4/letter/b/6bbea6/32.png) [@bup](https://boards.straightdope.com/u/bup)\ **Post date:** [May 11, 2006, 7:05pm UTC](https://boards.straightdope.com/t/when-did-we-find-out-that-sex-baby/356329/17 "2006-05-11T19:05:44Z")
Oh, but I’m an excellent coder. > [@ascenray](#): > > I just want to confirm that I read this same story as an undergraduate, but like the OP I don’t remember the details clearly. I seem to recall that it was on some Pacific island where the people spend a lot of time in the surf (harvesting sea cucumbers and such, perhaps?). The researcher tried to explain to some of the people that it was sexual intercourse that resulted in pregnancy, but he was not very successful in convincing them. The killer argument came from one man who said something like “I was gone for almost a year and my wife had a baby. That proves that sex is not the cause of pregnancy.” Apparently, the researcher didn’t think it wise to accuse the man’s wife of sexual infidelity. Two points: 1. Not to be a jerk, but I’d like to know what book. I’ve seen lots of social science textbooks with crap in them. It stretches credulity to think people wouldn’t notice family resemblances and come to the conclusion in any society. So I believe you, but I’d like to research that book. 2. If the story’s true, then I’d state that humans knew and then this society “unlearned” how to make babies (compare Christian Science, who’ve “unlearned” that humans are naturally mortal). So it’s unfair to use this as evidence that it took advanced society to get it. ---
**Author:** ![Acsenray](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/acsenray/32/4519_2.png) [@Acsenray](https://boards.straightdope.com/u/Acsenray)\ **Post date:** [May 11, 2006, 7:46pm UTC](https://boards.straightdope.com/t/when-did-we-find-out-that-sex-baby/356329/18 "2006-05-11T19:46:10Z")
> [@bup](#): > > 1. Not to be a jerk, but I’d like to know what book. It seems like that is exactly the question that the OP (and I) are asking as well. Neither of us has a clear enough memory of it. > [@](#): > > I’ve seen lots of social science textbooks with crap in them. No argument there. > [@](#): > > It stretches credulity to think people wouldn’t notice family resemblances and come to the conclusion in any society. I take your point, but at the same time, it seems to me that most human societies harbor delusions about a lot of big things. ---
**Author:** ![pravnik](https://avatars.discourse-cdn.com/v4/letter/p/8edcca/32.png) [@pravnik](https://boards.straightdope.com/u/pravnik)\ **Post date:** [May 11, 2006, 8:00pm UTC](https://boards.straightdope.com/t/when-did-we-find-out-that-sex-baby/356329/19 "2006-05-11T20:00:48Z")
The ethnography referred to in the OP is anthropologist Bronislaw Malinowski’s study of the Trobriand Islanders, _The Sexual Life of Savages_. The Trobrianders apparently beleived that pregnancy was caused by ancestral spirits as the mother swam in the lagoon. They weren’t stupid, though; they recognized as well as we do the resemblance between fathers and their children. They believed children were shaped to look like their mother’s husbands by sexual contact between conception and birth. ---
**Author:** ![pravnik](https://avatars.discourse-cdn.com/v4/letter/p/8edcca/32.png) [@pravnik](https://boards.straightdope.com/u/pravnik)\ **Post date:** [May 11, 2006, 10:37pm UTC](https://boards.straightdope.com/t/when-did-we-find-out-that-sex-baby/356329/20 "2006-05-11T22:37:41Z")
Scratched around a bit and found some links to some of Malinowski’s work. Here’s an explanation of the impregnation by ancestral spirits in _Baloma, Spirits of the Dead in the Trobriand Islands_: > [@](#): > > First of all, everybody in Kiriwina knows, and has not the slightest doubt about, the following propositions. The real cause of pregnancy is always a baloma, who is inserted into or enters the body of a woman, and without whose existence a woman could not become pregnant; all babies are made or come into existence (ibubulisi) in Tuma. These tenets form the main stratum of what can be termed popular or universal belief. If you question any man, woman, or even an intelligent child, you will obtain from him or her this information. But any further details are much less universally known; one obtains a fact here and a detail there, and some of them contradict the others, and none of them seems to loom particularly clear in the native mind, though here and there it is obvious that some of these beliefs influence behavior, and are connected with some customs. > > … > > Another cycle of beliefs and ideas about reincarnation implies a pronounced association between the sea and the spirit children. Thus I was told by several informants that after his transformation into a waiwaia, the spirit goes into the sea. The first version obtained (quoted above) implied that the spirit, after having washed on the seabeach and become rejuvenated, is taken up immediately by a female baloma and carried to Kiriwina. Other accounts state that the spirit, after being transformed, goes into the sea and dwells there for a time. There are several corollaries to this version. Thus in all the coastal villages on the western shore (where this information was collected) mature unmarried girls observe certain precautions when bathing. The spirit children are supposed to be concealed in the popewo, the floating sea scum; also in some stones called dukupi. They come along on large tree trunks (kaibilabala), and they may be attached to dead leaves (libulibu) floating on the surface. Thus when at certain times the wind and tide blow plenty of this stuff towards the shore, the girls are afraid of bathing in the sea, especially at high tide. [Link](http://www.sacred-texts.com/pac/baloma/bal06.htm) This is possibly the story **ascenray** remembers: > [@](#): > > The above-mentioned case of a native not being able to understand the question, Who is the father of an unmarried woman’s child? can be supplemented by two other instances concerning married women. When I asked my informants what would happen if a woman became pregnant in her husband’s absence, they calmly agreed that such cases might occur, and that there would be no trouble at all. One of them (I have not noted his name, and I do not remember it), volunteered his own case as an instance in point. He went to Samarai 68 with his white master, and stayed there for a year, as he said, during which time his wife became pregnant and gave birth to a child. He returned from Samarai, found the child, and it was all right. On further questioning, I came to the conclusion that the man was absent for about 8-10 months, so there is no urgent necessity to doubt the virtue of his wife, but it is characteristic: that the husband had not the slightest tendency to count the moons of his absence, and that he stated the broad approximate period of one year without the slightest concern. And the native in question was an intelligent man; he had been a long time with white men, as a “signed-on” boy, and he seemed to be by no means of a timorous or henpecked disposition. > > Again, when I once mentioned this matter in the presence of a few white men, resident in the Trobriands, Mr. Cameron, a planter of Kitava, told me a case which had struck him at that time, though he had not the slightest idea of the native ignorance of impregnation. A native of Kitava had been away for two years, signed on to a white man on Woodlark Island. After he came back, he found a baby born a couple of months before his return. He cheerfully accepted it as his own, and did not understand any taunts or allusions made by some white men, who asked him whether he had not better repudiate, or, at least, thoroughly thrash his wife. He found it not in the slightest degree suspicious or suggestive that his wife became pregnant about a year after his departure. These are two striking examples which I find in my notes; but I had before me a considerable amount of corroborating evidence derived from less telling facts, and from imaginary instances, discussed with independent informants. [Link](http://www.sacred-texts.com/pac/baloma/bal07.htm) [Next page](https://boards.straightdope.com/t/when-did-we-find-out-that-sex-baby/356329.md?page=2)