From Science:
Snowball, the dancing sulphur-crested cockatoo, is a big hit on YouTube–and now he's also a scientific sensation. Researchers have shown that the bird, who bobs his head and lifts his legs to the Backstreet Boys' song Everybody, is in fact listening to and following the beat. The findings–detailed in a pair of articles–challenge the notion that only humans have the neural wiring for dancing in time to music. “These are pathbreaking studies,” says Bruno Repp, a cognitive psychologist at Haskins Laboratories in New Haven, Connecticut.
Aniruddh Patel remembers the first time he saw Snowball on the Internet. A neurobiologist at the Neurosciences Institute in San Diego, California, Patel had argued in an earlier study that our talent for moving synchronously to a rhythmic beat is tied to our ability to learn and mimic sounds. “It seems to be a byproduct of a link between the auditory and motor parts of the brain,” he says. That seemed to rule out most animals except humans and parrots. Nevertheless, Patel was stunned to see Snowball's video. “My jaw hit the floor,” he says.
More here. (Note: Please watch the amazing video to the end!)