This video is a short description of how one baboon troop changed from being a typical highly violent baboon troop, to one with a very low level of violence.
Note, that the initiating event was removal of all violent males from their society.
The video below is a longer cut of some of the same video with more details.
Certainly humans on a small scale should be able to do much better with some careful planning.
More Sapolsk, please. His 12 billion part course on Human Behavioural Biology is good too (and also covers some of the same baboon research.
There is a Bedouin saying that encapsulates kin selection quite well:
“Me and my brother against my cousin. Me, my brother, and my cousin against the world.”
That’s a great quote. People attempting to design intentional communities of any stripe need to Watch all of Sapolski’s videos on behavioral biology a couple of times and probably take a little bit of Bedouin advice too.