Not Meeting Expectation

Interesting read but the authors try too hard to suggest an alternative in the mainstream approach to sex to the point of beautifying certain modern-day practices of multi-faceted sexual relationships / marital arrangements without showing the full picture of those models. The Chinese youths in the early 20th century voluntarily opted for monogamy because plenty of them witnessed enough of suffering in the centuries-old polygynous arrangement, and yet according to the authors, if this is a system more conforming to human nature, why did it not last forever? Similarly, from the book I also never figured out why the seemingly superior lifestyle of our hunter-gatherer ancestors had to switch to the agricultural society model.