I think Kant was the first to separate ethics & morality. My understanding is that morality equals a code of conduct. The codes develop by religion, customs, tradition, etc. Ethics develop when there is no right solution according any code and therefore some rules will be broken anyway (Vladimir Bibler). The responsibility in such a case rests with an individual’s conscience entirely. Ethics is something like “ultimately human unformalized way of conduct” which, metaphorically speaking, “falls in between moralities” and brings new moralities up.
Again: It is important to keep in mind the above noted difference for you cannot bring up, as some say, “the highest level of moral development” (a quote from a comment at a meet-up “Morality: Relative or Universal?”) through indoctrination. It “develops” in action when the entire responsibility is yours.
Evidently great many people conduct truly ethical feats, great or small. We know examples from revolutionary wars, arts, area of political & social reforms, even everyday life. Every time when someone prefers to tell the truth against profit or fear of punishment one behaves ethically. It is pure and simple and requires not functional explanation.
Some think that “rules” for humans’ and other species’ survival could be understood the same way. But “human survival” never meant physical survival. Rather it means preservation and development of humanity as such. This is why people would die for their values. That happens oftentimes even when a challenge comes from inside, not from outside. Like the case of Galileo. And the action which leads to such a situation we perceive as ultimately human, ethical, heroic, etc. We feel without a doubt that “human cause” is advanced there.
One may say people able for a real human action are not majority, or say, majority of those tested. But who counted that? People act ethically more often than it seems because human values, as I mentioned, are not functional, they are values in themselves. “You shalt not kill” is broken constantly and massively but humankind had survived, multiplied & developed. So, maybe it is not so very terrible to kill? It is. Why? Because it is ultimately inhuman. I believe, Aristotle would insisted that prohibition of murder is a truth which is evident in itself and requires not outer justification.