For her research into the impact of vocal pitch on people’s impressions of one another, the young academic deliberately chose this huntergatherer people – the last of its kind in East Africa – who, because of their nomadic lifestyle, have barely been exposed to the influences of civilization and thus are ignorant of the role models familiar to us who are depicted and amplified by the media. Coren Apicella assumed that the still largely unblemished culture of the Hadza (something we only encounter elsewhere amongst the Pygmy people of the rainforest region and the Bushmen of the desert steppes of South Africa) enables us to draw conclusions about man’s original psychological makeup. The researcher played the word "Hujambo" – a greeting in the commonly-used Swahili language – to the men and women of the Hadza in different variations of male and female voices, each of which had been modified in tone and pitch on a computer. The participants were then asked which of the speakers they could imagine as a marriage partner.

The result: The higher the women’s voices, the more attractive they were to men. Deeper women’s voices were, in contrast, assessed not emotionally but functionally, and connected with the economic division of labor practiced by the Hadza tribe and consequently associated with "good gatherers" (of berries, nuts, tubers and so on). Differences in the preferences of the women were less clear however. Only breastfeeding mothers preferred higher male voices. "Perhaps," Apicella speculates, "a higher voice is indicative of more provident behavior." According to this line of thinking, men with higher-pitched voices promised to be the better fathers.