Let's be fair, or, the gods were NOT crazy

The second half of the title of this post on fairness, and its deep roots in the human nature, come from the fact that the Kung! "bushmen" of the Kalahari desert are among the studied people who reinforce this.
Among the !Kung bushmen of the Kalahari in Africa, a successful hunter who may be inclined to swagger is kept in check by his compatriots through a ritualized game called “insulting the meat.”
That said, note that societies with written "commandments," etc. all are post-agricultural revolution, with private property and all its attendant problems, started us down the road of today's hypercapitalism.

And, yes, there's a strong evolutionary past for sharing more:

As Michael Tomasello of the Max Planck Institute for Evolutionary Anthropology has pointed out, you will never see two chimpanzees carrying a log together. The advent of agriculture and settled life may have thrown a few feudal monkeys and monarchs into the mix, but evolutionary theorists say our basic egalitarian leanings remain.

Studies have found that the thirst for fairness runs deep. As Ernst Fehr of the University of Zurich and his colleagues reported in the journal Nature, by the age of 6 or 7, children are zealously devoted to the equitable partitioning of goods, and they will choose to punish those who try to grab more than their arithmetically proper share of Smarties and jelly beans even when that means the punishers must sacrifice their own portion of treats.

Deeply evolutionary:

A sense of fairness is both cerebral and visceral, cortical and limbic. In the journal PLoS Biology, Katarina Gospic of the Karolinska Institute’s Osher Center in Stockholm and her colleagues analyzed brain scans of 35 subjects as they played the famed Ultimatum game, in which participants bargain over how to divide up a fixed sum of money. Immediately upon hearing an opponent propose a split of 80 percent me, 20 percent you, scanned subjects showed a burst of activity in the amygdala, the ancient seat of outrage and aggression, followed by the arousal of higher cortical domains associated with introspection, conflict resolution and upholding rules; and 40 percent of the time they angrily rejected the deal as unfair.

That first swift limbic kick proved key. When given a mild anti-anxiety drug that suppressed the amygdala response, subjects still said they viewed an 80-20 split as unjust, but their willingness to reject it outright dropped in half. “This indicates that the act of treating people fairly and implementing justice in society has evolutionary roots,“ Dr. Gospic said. “It increases our survival.”

That said, The Gods Must Be Crazy, and the Kung! behind it, aren't about Marxism post-dictatorship of the proletariat, either. Some hierarchy is normal:

Low hierarchy does not mean no hierarchy. Through ethnographic and cross-cultural studies, researchers have concluded that the basic template for human social groups is moderately but not unerringly egalitarian. They have found gradients of wealth and power among even the most nomadic groups, but such gradients tend to be mild. In a recent analysis of five hunter-gatherer populations, Eric Aiden Smith of the University of Washington and his colleagues found the average degree of income equality to be roughly half that seen in the United States, and close to the wealth distribution of Denmark.

I'd take Denmark over the U.S. any day.

And, stress that hypercapitalism is unnatural.

And, note that this shows a role for legitimate evolutionary psychology.
Other recent news has documented the role of anger in perhaps promoting human fairness; this only deepens that.