From Science:
The two sides of the brain are responsible for different tasks in many animals. In people, for example, the left side is usually the language center, whereas the right side handles more visual and spatial chores. Now, research on parrots shows that this separation increases brainpower. For many years, researchers thought that the division of labor in the brain, known as cerebral lateralization, was unique to humans. But recent research has shown that such lateralization is actually pervasive in vertebrates. A leading theory suggests that the attribute leads to faster, more accurate problem-solving. The theory holds true for minnows–the ones whose brains are lateralized are better at catching shrimp while simultaneously keeping an eye out for predators–but many other species haven't been tested.
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