I haven't seen this mentioned before, but apologies if it has been dealt with.
Isn't it possible that, to some extent at least, that our honor & ethical codes have evolved as a type of peacock feathers? That is, they evolved as markers of superior fitness because they make us more vulnerable. Peacock feathers are markers of fitness because they make the bird visible to predators - a bird that survives in spite of it can thus "claim" fitness. Similarly, ethical and honor codes constrain behavior: you are prevented from doing what would otherwise benefit you; those who could survive and flourish despite not stooping to theft or deception even when it could help them can thus signal fitness by saying "I am succeeding even though I have fewer options than others because I won't engage in theft or deception, therefore I am superior." Could the honor codes not have evolved this way? As badges of superiority?
The mention of "regularity" in this post convinces me more and more that true intelligence, at its core, is nothing else but the ability to make accurate predictions. That is, intelligence in any particular area is the ability to make accurate predictions about the future in that area. If you can predict cash flows accurately, you're an intelligent analyst. If you can predict game scores accurately, you're an intelligent gambler. Combining such intelligence with goals yields the following: if you can accurately predict whether your actions will bring you closer to your goal or not, you're intelligent. Thus, in a sense, there's nothing uniquely human: it's just a matter of how we developed our goals [through evolution], what tools we have to try to fulfill them [our brain, as evolved], and how good we are at that [how intelligent we are, which varies].