I am a bit traditional when it comes to equality between the sexes. I personally believe we were created to be different. Just as in nature - the males and females of the species take on different roles and purposes (in order for the species to survive) I believe that humans have instinctual differences between men and women.
I believe most men are born with an instinctual desire to protect and provide. I believe most women are born with an instinctual maternal desire to reproduce and care for children - as well as care for their mates in an emotional way.
I know there are outliers - and that not everyone fits into the pattern, but on the whole I think this is why there will always be a battle for equality of the sexes. Instinctively, we are not the same and therefore, not equal.
For many of the societies that Friedl analyzes the inequality between men and women exist in the capacity to own power and objectifications of it. For example, in hunter- gatherer social orders, the possession of animal meat constituted power. Those who were in possession of animal meat for consumption generated power over others, envy and want from others. It was primarily the job of the men to go out and hunt animals for their meat and this is why Friedl argues they enjoyed the benefits of power. In this light, there is an economic argument being made. The owning of meat was the owning of the means of production, the method by which that society functioned. If no one owned the meat or there was not meat to be owned, people would die. In the end, it is this consumption of meat and the regaling of the men who were able to go out and get it that caused men to be vaulted above women. For their part, the collection of berries and vegetables was a task tended to by women, and something that did not register on the level of collecting meat. Another example would be the Eskimo society that took this to another level. Men who were traders and definitely owners of the means of production were allowed to utilize their wives as means to more profitable ends, in terms of being able to utilize their spouses as a way to generate more profit. In both settings, one sees that the difference between the genders was that one was able to step outside the realm of the private and engage in activities deemed as socially meritorious over the other gender, who was relegated to a peripheral role in this process. This is one explanation that Friedl gives as to why gender discrimination existed back then and why equality between the sexes was rare.