ABCMusic and dance are far from idle pastimes. They are universal forms of expression and deeply rewarding activities that fulfil diverse social functions. Both feature in all the world’s cultures and throughout history. A common feature of music and dance is rhythmic movement, which is often timed with a regular pulse-like beat. But the human capacity for rhythm presents something of a puzzle. Even though rhythmic coordination seems fundamental to human nature, people vary widely in ability. Some have the machine-like precision of Michael Jackson, others are closer to the case of “beat-deaf” Mathieu. What are the underlying causes of these individual differences?