There seem to be some features of human experience that are universal, such as mating, birth, child rearing, property, some form of social organization, some system of justice, suffering, and death....

There seem to be some features of human experience that are universal, such as mating, birth, child rearing, property, some form of social organization, some system of justice, suffering, and death. How does the relativist explain the fact that every society has some form of morality based on these and other common features of human life?