Because monkeys had been shown to use mirrors to locate food, Donald M. Broom of the University of Cambridge and his colleagues decided to check for a similar sort of so-called assessment awareness in pigs. They began by exposing seven 4-to-8-week-old pigs to five-hour stints with a mirror and recording their reactions. The pigs were fascinated, pointing their snouts toward the mirror, hesitating, vocalizing, edging closer, walking up and nuzzling the surface, looking at their image from different angles, looking behind the mirror. When the mirror was placed in their pen a day later, the glass-savvy pigs greeted it with a big ho-hum.

Next, the researchers put the mirror in the enclosure, along with a bowl of food that could not be directly seen but whose image was reflected in the mirror. They then compared the responses of the mirror-experienced pigs with a group of mirror-naïve pigs. On spotting the virtual food in the mirror, the experienced pigs turned away and within an average of 23 seconds had found the food. But the naïve pigs took the reflection for reality and sought in vain to find the bowl by rooting around behind the mirror. No doubt the poor frustrated little pigs couldn't wait to get home, crack open a beer and turn on the TV.

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If we can teach pigs the difference between illusory images of reflection and real substance, why can't we teach the same awareness to children, or even adults of our own species?


A