Pity that I cannot cite the source, so don't quote me on this, but: I came across a post a while ago on Tumblr regarding infanticide rates in ancient hunter-gathering societies. Archaeologists have estimated that there was a high rate of female infanticide, in order to ensure a greater number of men within any given band -- but why? Why bother?
The same study that this tumblr post cited also said that there was something like a 25% mortality rate among young men in these bands, primarily because of raids from enemy tribes. So it makes sense that you would want to create an imbalance of men, because you want to have a surplus of expendables for the warfare that is a constant feature of life.
One might say it's better to be a woman in such circumstances, only the women would have been married off to an older and more politically powerful fellow, who had a bunch of wives and commanded them to produce children to replace warriors lost in battle. And also being a woman meant you might get carried off by raiders and forced to marry the bigamists of some other tribe.
So the men were cannon fodder and the woman were breeding cattle, both of them using up their lives for the sake of the concentration of goods and territory within the hands of a small number of people. In all the back-and-forth between men's rights activists and feminists, it's important to remember that things have not changed all that much, and our common enemy remains the folks with an outsized proportion of wealth and political influence.