One of the most spectacular synchronizing crickets is the snowy tree cricket, Oecanthus fultoni. This slide shows the calling song of the ‘thermometer cricket’. The song is a rhythmic series of chirps and like most cricket songs each chirp is composed of pulses. However, within a chirp the pulses come in groups. Typically a pair of pulses is followed by one or more groups of three pulses. The typical 8-pulse chirp is shown above, but males can drop or add 3-pulse groups to their chirp and thus produce 2, 5, 11 or 14-pulse chirps. The chirp rhythm is temperature dependent. Data from Walker showing the chirps rate as a function of temperature are plotted on the right. A good rule of thumb: count the number of chirps in 13 seconds and add 40 to get the temperature in ^oF. The temporal rhythm of the song is important in female phonotaxis and the female’s response (preference) changes in the same linear manner with temperature.