Cricket

Crickets demonstrate multiple acoustic communication principles. When a male cricket rubs its wings together (stridulation), it creates pressure waves at frequencies between 2,000 and 8,000 Hz - perfectly matched to the resonant frequency of female tympanic organs. The call can travel 30 meters through grassland. Male cricket choruses in Trinidad synchronize their chirps with millisecond precision. The snowy tree cricket chirps at a rate precisely correlated with temperature (count chirps in 15 seconds, add 40, and you have the temperature in Fahrenheit). Two-spotted crickets on Kauai evolved 'flatwing' males within twenty generations to avoid parasitoid flies - a mutation eliminating wing structures needed for calling.