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#16: Cricket Ears



Litinsects #16: Cricket Ears

Towards the beginning of this series, I posted about how grasshoppers hear using a TYMPANAL ORGAN, which is located on each side of their abdomen. Crickets, as well as grasshoppers, belong to the order ORTHOPTERA 🦗 (ortho = straight, ptera = wing) and also hear using tympana. Theirs, however, are located somewhere completely different and rather strange: their legs.

  • Cricket tympana are located on the TIBIA of their forelegs
  • Crickets call... and in order to find each other, they must obviously be able to tell where a call is coming from. Underneath the tympanum there is a network of pathways through which sounds can travel through the body and between the left and right tympana. The animals can gauge the DIRECTIONALITY of a sound depending on how sound waves act on both the external AND the internal surfaces of their tympana! This difference of pressure is vital for localizing the calls of fellow crickets.
  • Crickets call by scraping their wings together (different than how grasshoppers do it). Each species calls in a distinct frequency with a distinct pattern
  • Only male crickets sing. They have a “calling song” to attract females, a “courtship song”, and a “rivalry song” when coming into contact with rival males
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