Using mathematical analysis, researchers from the Max Planck Institute in Frankfurt, Germany, found that the thrush nightingale can sing in an off-beat “swing time” like jazz musicians. Some experts surmise that they do this to make their calls to mates more noticeable or to help them dance during mating rituals, or it may be that they simply get too excited and lose control of their rhythm. The nightingale is not the only species found to improvise a tune. The Veery thrush of North America also swings. Another study showed that the hermit thrush uses the fundamental musical intervals found in human music in its songs.