Male Java sparrows are songbirds — and, scientists reported on Wednesday, natural percussionists.

The sparrows click their bills against a hard surface while singing. That clicking is done in coordination with the song, much as a percussion instrument accompanies a melody. Researchers at Hokkaido University in Japan observed the birds producing clicks frequently toward the beginning of their songs and around specific notes. Birds that were related produced similar percussive patterns, but whether this behavior is learned or innate is unclear.