Back when Malinowski was doing his field work, he was amazed that islanders could freely have premarital sex and yet still found it desirable to get married.
...girls want sex just as much as guys, kids start having sex at a very young age — 6-8 for the girls and 10-12 for the guys — with no social stigma, there are few customs about dating to inhibit “hooking up”...
Of course, much of the story of a Trobriand’s intimate life is the same: initial attractions budding into lasting relationships, etc. And then, out of nowhere, Malinowski drops in something totally bizarre. The islanders don’t kiss, he explains. Instead, they scratch. The girls scratch the guys so hard that they draw blood and, if the guys can withstand the pain, then they move forward to having sex...while everybody is having sex whenever they want, premarital meal-sharing is a big no-no. You’re not supposed to go out for dinner together until after you get married.
But the most fascinating and strange part about the islanders are their beliefs on the subject of pregnancy, also described in Malinowski’s classic article “Baloma: The Spirits of the Dead in the Trobriand Islands”. When people die, you see, their spirit takes a canoe to the island of Tuma...When the spirit gets old and wrinkled it shrugs off its skin and turns back into an embryo, which a spirit then takes back to the island and inserts into a woman. This, you see, is how women get pregnant.
That’s right. The islanders do not believe that sex causes pregnancy. They don’t believe in physiological fatherhood.
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They argued the case quite logically. After all, they noted, one fellow went on an expedition for a year or two and when he came back, he had a new son. He obviously wasn’t having sex with her while he was away, so where did the kid come from? ... And, they note, there are some really hideous people on the island who nobody would dare have sex with, yet they manage to become pregnant.
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They also argue the other way: people on the island are having sex all the time from a very early age and yet they very rarely get pregnant.
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It is speculated that the yams that form the basis of the island diet have a contraceptive agent in them ... which conveniently explains quite a bit, including the low birthrate despite the high level of sexual activity.
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...the society is necessarily matrilineal, since fathers have no technical lineage. Yet sociological fathers (the mother’s husband), Malinowski notes, show more love and care for their children than most he’s seen in Europe.
Furthermore, they believe the same rules apply to the rest of the animal kingdom. This is what clinches it for Malinowski — despite all the effort they go to to raise pigs, they insist that pigs also reproduce asexually. They never attempt to breed pigs; indeed, they castrate all the male pigs they have. (To them this is further proof — we castrated all the pigs and yet they keep having children! Malinowski notes that the domestic pigs often sneak off to canoodle with those in the wild.)