Depth of the Kindness Hormone Appears to Know Some Bounds

There may be a chemical reason for tribalism.

From "Depth of the Kindness Hormone Appears to Know Some Bounds", Nicholas Wade.

"Oxytocin has been described as the hormone of love. This tiny chemical, released from the hypothalamus region of the brain, gives rat mothers the urge to nurse their pups, keeps male prairie voles monogamous and, even more remarkable, makes people trust each other more.

Yes, you knew there had to be a catch. As oxytocin comes into sharper focus, its social radius of action turns out to have definite limits. The love and trust it promotes are not toward the world in general, just toward a person’s in-group. Oxytocin turns out to be the hormone of the clan, not of universal brotherhood. Psychologists trying to specify its role have now concluded it is the agent of ethnocentrism."

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“In the ancestral environment it was very important for people to detect in others whether they had a long-term commitment to the group,”