Our bloody nature, it can now be argued in the context of modern biology, is ingrained because group-versus-group was a principal driving force that made us what we are. In prehistory, group selection lifted hominids to heights of solidarity, to genius, to enterprise. And to fear.
A recent article in The Guardian “How to be Human: The Man Who Was Raised by Wolves” tells the story of a boy who was sold into slavery (yes, slavery, unbelievable, it certainly wasn’t common) during Spain’s turbulent post-war period. Abused by his master and forced to work as a shepherd in Spain’s remote Sierra Morena mountain range, Marcos Rodríguez Pantoja eventually escaped by taking refuge with a pack of wolves.