Why do the hairs in the cochlea differ in length?

The hairs in the cochlea, known as hair cells, differ in length primarily to detect different sound frequencies. The cochlea is a spiral-shaped organ in the inner ear that converts sound vibrations into neural signals. It contains a basilar membrane that varies in stiffness and width along its length.

Shorter hair cells are located at the base of the cochlea, while longer ones are found at the apex. This anatomical arrangement allows different sections of the cochlea to respond to varying frequencies of sound. High-frequency sounds stimulate the hair cells at the base, while low-frequency sounds affect those closer to the apex. As a result, the varying lengths of the hair cells contribute to the cochlea's ability to identify a wide range of sound frequencies, enabling precise sound detection and processing in the auditory system.