I always preferred to look at morals as survival strategies for societies. From this point of view they do not have to be universal to work - its enough that they skew the probablity a bit towards survival of given group and the rest is just some version of Darwins Game of Life.
Obviously they don't have to be universal to work, that's my whole post - they aren't, and humanity was pretty successful in settling every last piece of this planet.
