This new book emphasizes how our modern cultures have changed or suppressed the expression of some of our "Stone Age" and genetic sexual and reproductive adaptations. These biological adaptations often can still be found in modern humans, in their original Stone Age form---- or modified to some degree---- In the DNA of our present hunter-gatherer populations. For example, I'll review----with up-to-date research input----- how our maladaptive cultural choices have changed natural breast-feeding into artificial bottle-feeding by many modern women, and the effects of this choice or necessity on child and maternal health. Certainly, most present-day people would not be able to----and probably wouldn't want to----return completely to our hunter-gatherer ways; all I am saying is that we can choose to return to the more natural expression of SOME of our Stone Age reproductive and sexual adaptations. Please a few of the chapters of this new book will contain UPDATED AND MUCH REVISED versions of portions of the "Boxes" in Human Reproductive Biology (2014), by Richard E. Jones and Kristin H. Lopez, with permission previously obtained from Academic Press/Elsevier.