Tribalism will always exist, though it may resolve around other things than religion, skin color or national allegiance. Life happens on the boundaries between

Tribalism will always exist, though it may resolve around other things than religion, skin color or national allegiance. Life happens on the boundaries between chaos and stasis (what rayiner says in another comment in different words). It's not a coincidence that life depends on liquid water, the boundary between chaotic water vapor and static ice. It's not a coincidence that either too low or too high a mutation rate would break evolution. This same holds true for all other life-like complex systems such as human culture and society.