What you cite about cooperation rings a bell from Joshua Greene's book Moral Tribes[1]. Greene is an experimental psychologist, neuroscientist, and a philosoph

What you cite about cooperation rings a bell from Joshua Greene's book Moral Tribes[1]. Greene is an experimental psychologist, neuroscientist, and a philosopher. He did extensive research, including fMRI brain studies of the famous trolley problem[2], prisoner's dilemma situations and such other cooperation/desertion scenarios. And sure enough, some of Greene's papers are cited in the paper you mentioned. His book[1] is worth reading. I picked it up after hearing about it in Robert Sapolsky's, Behave. And for balance, here's an interesting paper[3] critiquing some of Greene's ideas from Moral Tribes. [1] https://www.joshua-greene.net/moral-tribes https://www.joshua-greene.net/moral-tribes [2] https://en.wikipedia.org/wiki/Trolley_problem https://en.wikipedia.org/wiki/Trolley_problem [3] "Metamorality without Moral Truth" — https://link.springer.com/article/10.1007/s12152-018-9378-3 https://link.springer.com/article/10.1007/s12152-018-9378-3