(The Atlantic) Barry and Bonnie Hewlett had been studying the Aka and Ngandu people of central Africa for many years before they began to specifically study the groups' sexuality. As they reported in the journal African Study Monographs, the married couple of anthropologists from Washington State University "decided to systematically study sexual behavior after several campfire discussions with married middle-aged Aka men who mentioned in passing that they had sex three or four times during the night. At first [they] thought it was just men telling their stories, but we talked to women and they verified the men's assertions."
In turning to a dedicated study of sex practices, the Hewletts formally confirmed that the campfire stories were no mere fish tales. Married Aka and Ngandu men and women consistently reported having sex multiple times in a single night. But in the process of verifying this, the Hewletts also incidentally found that homosexuality and masturbation appeared to be foreign to both groups.