Our research and that of other scientists suggests that the vagus nerve may be a physiological system that supports caretaking and altruism. We have found that activation of the vagus nerve is associated with feelings of compassion and the ethical intuition that humans from different social groups (even adversarial ones) share a common humanity. People who have high vagus nerve activation in a resting state, we have found, are prone to feeling emotions that promote altruism—compassion, gratitude, love, happiness. Arizona State University psychologist Nancy Eisenberg has found that children with elevated vagal tone (high baseline vagus nerve activity) are more cooperative and likely to give. This area of study is the beginning of a fascinating new argument about altruism—that a branch of our nervous system evolved to support such behavior.