To out-group-members, oxytocin makes you crappier - less cooperative and more preemptively aggressive. It's not the luv hormone. It's the in-group parochialism/xenophobia hormone.
Robert M. SapolskyDigestion is quickly shut down during stressโฆThe parasympathetic nervous system, perfect for all that calm, vegetative physiology, normally mediates the actions of digestion. Along comes stress: turn off parasympathetic, turn on the sympathetic, and forget about digestion.
Robert M. SapolskyStress is not a state of mind... it's measurable and dangerous, and humans can't seem to find their off-switch.
Robert M. SapolskyFor example, most mammals are either monogamous or polygamous. But as every poet or divorce attorney will tell you, humans are confused - After all, we have monogamy, polygamy, polyandry, celibacy, and so on. In terms of the most unique thing we do socially, my vote goes to something we invented alongside cities - we have lots of anonymous interactions and interactions with strangers. That has shaped us enormously.
Robert M. SapolskyThere's the complex categorization of low warmth/high competence. This is the hostile stereotype of Asian Americans by white America, of Jews in Europe, of Indo-Pakistanis in East Africa, of Lebanese in West Africa, of ethnic Chinese in Indonesia, and of the rich by the poor most everywhere. It's the same low-high derogation: They're cold, greedy, clannish - -but, dang, they're sure good at making money and you should go to one who is a doctor if you're seriously sick.
Robert M. Sapolsky