more expendable simply due to mechanics. I like the thought experiment :If you have two tribes of 50 men and 50 women, and the men of each tribe go to war there are still 50 women and the remaining men can commit to multiple wives. The tribe can still grow by at least 50, not accounting for twins and miscarriage. However, if the women went to fight the battle and only half of the women returned, each tribe could only grow by 25 persons (also possible that the remaining 50 men