Is altruism a result of human societal values, or is it something innate that evolved biologically? Psychologist Dacher Keltner claims the latter may be the case:

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.

If you want the opposite take (which, for what it’s worth, reads a lot less like the jacket copy for a spiritual self-help book), look no further than sf writer and biologist Peter Watts:

Men, like most male mammals, like to acquire resources. When they’re not especially horny, they’re as likely to go for furniture and big-screen TVs — i.e., major, nonportable items that remain in the home — as anything else. When they’re horny, however, they’d rather buy bling and fast cars — flashy stuff they can take on the road to attract mates. Also, when in a horny mood, they’re more likely to give publicly to panhandlers (also to indulge in risky/heroic behaviour). In other words, both conspicuous consumption and conspicuous generosity are just ways of attracting mates: hey baby, lookit me! I’ve got so much money I can just give it away!…

I wonder if we’ll ever be ale to answer this question definitively? Whether we’ll like the answer is another question entirely…