pt. 1. Who we all used to be. The origins of humans and the control of nature -- pt. 2. Why we sometimes need worms and whether or not you should rewild your gut. When good bodies go bad (and why) ; The pronghorn principle and what our guts flee ; The dirty realities of what to do when you are sick and missing your worms -- pt. 3. What your appendix does and how it has changed. Several things the gut knows and the brain ignores ; I need my appendix (and so do my bacteria) -- pt. 4. How we tried to tame cows (and crops) but instead they tamed us, and why it made some of us fat. When cows and grass domesticated humans ; So who cares if your ancestors sucked milk from aurochsen? -- pt. 5. How predators left us scared, pathos-ridden and covered in goose bumps. We were hunted, which is why all of us are afraid some of the time and some of us are afraid all of the time ; From flight to fight ; Vermeij's law of evolutionary consequences and how snakes made the world ; Choosing who lives -- pt. 6. The pathogens that left us hairless and xenophobic. How lice and ticks (and their pathogens) made us naked and gave us skin cancer ; How the pathogens that made us naked also made us xenophobic, collectivist, and disgusted -- pt. 7. The future of human nature. The reluctant revolutionary of hope.