The Domesticated Penis: How Womanhood Has Shaped Manhood
by Loretta A. Cormier, Sharyn R. Jones.
They have periodic ritual sex time where men and women engage in sex with multiple partners. The expectation for women (married or not) is that they should have sex with any man who asks. To refuse such a request is considered quite rude and being “stingy with one’s genitals”. Here, a woman who has sex with a man who she may not desire is not traumatized; rather, it is more a matter of being polite and generous and helping to promote group harmony.
https://books.google.co.nz/books?id=qAvECgAAQBAJ

Review
The Domesticated Penis challenges long-held assumptions that, in the development of Homo sapiens, form follows function alone. In this fascinating exploration, Loretta A. Cormier and Sharyn R. Jones explain the critical contribution that conscious female selection has made to the attributes of the modern male phallus.
Synthesizing a wealth of robust scholarship from the fields of archaeology, cultural anthropology, evolutionary theory, and primatology, the authors successfully dismantle the orthodox view that each part of the human anatomy has followed a vector of development along which only changes and mutations that increased functional utility were retained and extended. Their research animates our understanding of human morphology with insights about how choices early females made shaped the male reproductive anatomy.
In crisp and droll prose, Cormier’s and Jones’s rigorous scholarship incorporates engaging examples and lore about the human phallus in a variety of foraging, agrarian, and contemporary cultures. By detailing how female selection in mating led directly to a matrix of anatomical attributes in the male, their findings illuminate how the penis also acquired a matrix of attributes of the imagination and mythical powers—powers to be assuaged, channeled, or deployed for building productive societies.
These analyses offer a highly persuasive alternative to moribund biological and behavioral assumptions about prehistoric alpha males as well as the distortions such assumptions give rise to in contemporary popular culture. In this anthropological tour de force, Cormier and Jones transcend reductive gender stereotypes and bring to our concepts of evolutional biomechanics an invigorating new balance and nuance.
South African survey of approximately 1,700 men, 27.6 percent admitted to having raped a woman or girl (4.9 percent within the last year). 46.3 % reported more than one victim. 26.2 percent of the rape victims were under the age of 14, 72.7% under 19.
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Canela of the Amazonia. They have periodic ritual sex time where men and women engage in sex with multiple partners. The expectation for women (married or not) is that they should have sex with any man who asks. To refuse such a request is considered quite rude and being “stingy with one’s genitals”. Here, a woman who has sex with a man who she may not desire is not traumatized; rather, it is more a matter of being polite and generous and helping to promote group harmony.