The pathological Seattle four-way stop—drivers sitting, gesturing at
one another to go ahead rather than taking the right of way—is
fundamentally rodentlike. You aren’t being polite; you’re acting out a
deeply programmed instinct to compete for the title of Most Helpful.
It’s the passive-aggressive peacock show—with brown feathers fluttering
in the air. The result: We all sit and wait for someone to be the least
nice. Consider the standoff at the four-way stop a gift from our
terrified pint-sized furry ancestors. Welcome to the bizarre science
behind altruism.
For our little genetic predecessors like the mice, it’s always been
key to get in a good group. Publicly demonstrating your
selflessness—letting everyone else see you’ll wait until the end of
time for your turn—is a powerful signal that you’re ready to cooperate,
a way of building a good reputation. Being the most magnanimous mouse
buys the goodwill of the group, which comes in handy later. Your
actions now determine how you’ll be treated in the future. If you
aggressively steal someone’s turn at the stop, they might give you the
finger and tailgate you. If you let someone go first, someone similar
might let you merge tomorrow. This sort of direct or indirect
reciprocity—a reward or punishment for prior behavior—takes complex
thinking. Until some recent experiments, scientists assumed only humans
had enough brainpower.
Rodents are essentially teeth and genitals. A mouse can’t sit around
and think, “Herbert is really great. Next time a hawk comes by, I’ll
squeak to warn him.” Keeping track of many individuals is beyond such a
tiny brain. Recognizing the helpfulness of a given group is a much
easier task; all it takes is remembering how another last treated you.
In a helpful community, we’re more likely to contribute. We simply
leave when repeatedly treated badly. (Welcome, Southern Californians.)
Scientists have found this sort of behavior in animals. A rat helped by
another rat is more likely to help a third rat get food—even if all the
rats are strangers to one another. Chimpanzees who sense they are in an
agreeable group will help another get an out-of-reach object or food—so
will an 18-month-old human.
Increasing evidence shows that even simple mammals can feel empathy
for the familiar, something also assumed to be limited to adult humans.
Mice become agitated if their cagemates are harmed, but stay calm when
unknown mice are in pain. (Mice will also eat their cagemates; there
are limits.) Empathy for those in our circle seems ground into us. We
can only harm another without feeling their pain if we cast them out of
our group.
Long attributed to social conditioning, civilization, or religion,
our ability to empathize and act altruistically toward others appears
in part to be an inherent trait of mammals. Evolution has noted the
cost of ruthlessness; cooperation is powerful enough to be written into
our genes. Still, when it’s your turn at the four-way stop, do the
right thing: go.
