If you put chimpanzees from different communities together you can expect mayhem - they are not keen on treating each other nicely. There is closely related species of apes, however, whose members have countless encounters with unrelated specimen on a daily basis and yet almost all get through the day in one piece - that species is us, homo sapiens. But what makes us get along, most of the time?
Morality as such is, perhaps surprisingly, not a mainstream research topic in social psychology. Most textbooks in the field do not even mention the term morality at all (and focus on 'prosociality' instead). This relative lack of 'coverage' might have to do with the difficulty of operationalising 'morality' in a fitting way (more on this below). However, morality certainly is a social phenomenon and therefore the collection of Fargas, Jussim, and Van Lange is certainly a step in the right direction; it offers an extensive overview of the field and is suggestive of the vast potential of studying morality through the lens of social psychology.