The Yanomamö practice infanticide — like many societies:
Dennett: Would you imagine discovering a behavior, a practice, a policy in a tribe that was so repugnant to Western sensibilities that you would decide not to write about that?
Chagnon: Well, the Yanomamö practice infanticide occasionally, and it’s for a variety of reasons. One of them being if they suspect that the newborn infant is deformed, and it can be traced right back to parental investment. Why invest in a losing prospect? Let’s terminate the infant now and start anew. Another example of infanticide is, this is even rarer, that some guy was cuckolded by, or suspected he was cuckolded by some other guy, and he puts pressure on his wife to kill the new infant. That’s not very common, but I’ve heard of it. And I began reporting, as soon as I learned this, that the Yanomamö practice infanticide, and I didn’t make a big case out of it. When I learned that a deputado in the Venezuelan government — which is basically like a representative or a senator — had learned that there were people in her country that were killing their own children, she wanted to go in and arrest these people and put them in jail. So I stopped reporting any information I acquired about Yanomamö infanticide, not because it was disgusting to Westerners, because I’ll bet if you looked at the abortion rate in Venezuela in middle class women, their rate of abortion would be much, much higher than the Yanomamö infanticide.
Pinker: Well, in fact, historically, I’ve seen an estimate — it averages over many peoples, and there’s a lot of variation underneath it — that the traditional infanticide rate was about 15 percent of live births, which is pretty close to the …
Chagnon: In Western culture?
Pinker: No No, in non-Western cultures. Which is pretty close to the abortion rate in the West, until recently.
Chagnon: Oh, really?
Pinker: The abortion rate has since then come down. But there is something to the idea that abortion in the West serves a similar purpose to infanticide in traditional cultures.
Chagnon: That’s right. It’s a definitional matter, so don’t get uptight about Yanomamö practicing infanticide when your sister or your wife has had an abortion. I mean if you want to make a moral issue out of it, let’s include everybody.