Studies of Snowball the dancing cockatoo (who had a round of television fame in the late ’00s) “turned out to be just the prelude to a new concerto of research on musicality in the animal kingdom. In recent years, scientists have tested various species and found evidence that nonvocal learners such as sea lions and bonobos have rhythm too. In parallel, pioneering studies have begun to elucidate how the brain tracks a beat.”