[beagle3]

As far as one can tell, social animals show something equivalent to morals in every experiment we can devise -- and in the vast majority of cases, it is not a learned trait (elephants being the best known counterexample in that their cultural norms and morals are indeed learned).

We can't really experiment with humans, but the few experiments that have cleared ethical committees, it appears that babies as young as 6 months have a sense of equality and justice, see e.g. [0]

[0] http://www.wired.co.uk/article/babies-understand-hero-action...