I've heard it said that things like game theory threw theologists into a tizzy because it provided a way for there to be morals without God. I'm not sure if this argument works with TheLady's definition of morals, but it does for other ways of looking at them.
The morals-implies-God argument runs as follows: if there were no God, there would be no reason for anyone to do anything against his own immediate self-interest. As TheLady puts it, morals have to be imposed externally. God provides the ultimate authority figure who lays down the basic laws to force people to work together and think as a group rather than as individuals. Without such an external imposition of order, people's self-interest would tear any society apart. Therefore, no society could exist without some sort of divine influence to get it started: laws must come from God.
But studies of game theory and such things as the Prisoner's Dilemma give an alternative (just as evolution provided an alternative to creation). It turns out that, yes, a society in which people are completely self-motivated will tear itself apart, but if some people, perhaps by chance or in moments of weakness, decide to forgo their own interests in preference to the common good, the society as a whole is stronger than it would otherwise be. In Prisoner's Dilemma terms, a society of co-operators will as a whole be stronger than one of defectors. And so such societies will survive, while self-motivated groups will not be able to compete. And societies that enforce co-operation will similarly last, and so on.
I suppose you don't really need studies of game theory to see this; the concept is pretty obvious. But the point is that morals could then evolve, without necessitating a divine source.
Me, a practicing Nice Jewish Boy writing such an atheistic post? What's the world coming to?