Carl Zimmer reviews research that suggests nativism has its roots in biology:

Over the past few years, Mark Schaller, a psychologist at the University of British Columbia, has been developing an intriguing theory that behavior can be just as effective as microbiology at warding off disease. According to this theory, we have what Schaller calls a “behavioral immune system.” It’s a way of responding to the outside world, and to the people around us, that is so deeply embedded in our minds that we are hardly aware of it.

Schaller and his colleagues have been busily running psychological experiments to test his hypothesis. The results so far are preliminary but provocative. If Schaller is right, this behavioral immune system may prove to have a big influence on our day-to-day lives. It might even influence human nature on a global scale, shaping cultures around the world.

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