When you have a lot of sheep around, evolution is bound to come up with a sheep that feeds on other sheep. For such mutants, having 'social camouflage' is a critical trait, because otherwise they would be losing to normal sheep due to their tit-for-tatting.
As for the advantage, it seems pretty clear to me: higher chances at being the alpha-male(female?), plus the resource advantage due to not having the ability for reciprocal altruism (and the ability to get away with that).
All few human psychopaths I have personally met were natural-born leaders. One is now occupying a high-level position within a successful company that produces manupulative F2P games. Another was a woman who, despite her being deaf-mute, was able to organize a successful remote web studio (before it fell apart due to her politicking and other members, including me, bailing out).
Also, quoting Wikipedia: "In Mongolia alone as many as 200,000 of the country's 2 million people could be [Genghis] Khan descendants".
Edit: if I remember correctly, Richard Dawkins' The Selfish Gene discussed cheaters (that is, individuals who didn't reciprocate) as being a viable evolutionary strategy, as long as they are in a minority.
As for the advantage, it seems pretty clear to me: higher chances at being the alpha-male(female?), plus the resource advantage due to not having the ability for reciprocal altruism (and the ability to get away with that).
All few human psychopaths I have personally met were natural-born leaders. One is now occupying a high-level position within a successful company that produces manupulative F2P games. Another was a woman who, despite her being deaf-mute, was able to organize a successful remote web studio (before it fell apart due to her politicking and other members, including me, bailing out).
Also, quoting Wikipedia: "In Mongolia alone as many as 200,000 of the country's 2 million people could be [Genghis] Khan descendants".
Edit: if I remember correctly, Richard Dawkins' The Selfish Gene discussed cheaters (that is, individuals who didn't reciprocate) as being a viable evolutionary strategy, as long as they are in a minority.