David’s father, Kenneth, was an anthropology student at the University of Pennsylvania who, under the tutelage of the prominent scholar Napoleon Chagnon, made his first trek to the Amazon in 1975. “I was older than the rest of the team, and a little more arrogant,” he says. Exasperated, Chagnon rid himself of Kenneth, sending him to the most remote part of the jungle.

There, he stumbled upon Yarima’s tribe. He was enthralled and fascinated, and made so many return trips that the Yanomami came to regard Kenneth as one of their own. “The head man of the village said, ‘You know, have a wife — you’ve been here for so long.’ ”

In 1978, he was offered Yarima, who was then about 9 to 12. Good was 36. He saw no real problem…

Kenneth has always taken umbrage at the obvious question: How old was Yarima when their union was consummated? “PBS asked me that once, and I said, ‘You can be damn sure that she was the age of consent in most states and many countries around the world,’ ” he says. “Which I think is 13. The cultural age is what’s important down there. Don’t I have the right to do this or that in another culture?”