One of the ways humans have distinguished themselves from our animal cousins is in creating a larger view of what we consider a society. Biologist Mark W. Moffett joins host Krys Boyd to talk about how humans have evolved to get along with one another while other primates won’t think twice about killing a fellow chimp they don’t recognize. Moffett’s book is called “The Human Swarm: How Our Societies Arise, Thrive, and Fall” (Basic Books).