Grasshoppers do not have ears on their heads, but instead process sound through small, drum-like membranes called tympana located on either side of their abdomen, tucked just beneath their wings.

An ear built into the abdomen

A grasshopper’s tympanum is a thin, flexible membrane on each side of the first abdominal segment, usually hidden beneath the wings. When sound reaches it, changing air pressure makes the membrane move in and out. Sensory cells attached to the hearing organ detect those movements and convert them into nerve signals the nervous system can process.

So the grasshopper is not hearing with its head—but the membranes are still ears in the functional sense. Their tucked-away position also means the wings can partly cover them without preventing sound from reaching them.

Listening for a particular call

In species that produce mating songs, the hearing system is responsive to the sound patterns that matter to them. A call with the right pitch and rhythm can drive the tympanum and sensory cells more effectively than sounds outside that range. This is not conscious recognition of a tune; it is a physical and neural response that helps the insect detect a relevant signal amid other noises.

That sensitivity links the grasshopper’s song and its hearing: a caller produces vibrations, and a potential mate’s abdominal membranes turn them into signals the nervous system can use. The sound is received at the body’s sides, where a hidden membrane begins the work of listening.