Chimpanzee Politics is as depressing a text as they come. Frans de Waal studies a group of chimpanzees and records their social changes over time.

Through de Waal's interpretation of events, we witness coalition-building, pecking orders, power struggles, and assassination. These are only good or bad depending on your view of what life should be like. If you're an alpha male, you want to maintain your sexual monopoly; if you're a lower-ranking male, you want to depower the alpha male to get a better chance of procreating; if you're a female, you want a stable world in which to raise your children. Add a bunch of spare brain-power (some stoopid human gives you food and keeps you housed), and you have a recipe for all-out social warfare. Absolutely disgusting.