Why do children tend to have high-pitched voices, and why do males typically have lower voices than females do?

Children tend to have high pitched voice because the larynx is small and thin.

Males have lower voices because they have larger and thicker larynx.

Explanation:

Its the larynx that makes noise, so known as voice box. Changes in the length and thickness of larynx cause voice modulation. This modulation helps male getting a deeper voice.

The larynx of children are small and thin which helps to a high pitched voice and during the time of puberty, larynx starts growing and thickening.This makes the voice low pitched and deep.

Thus, its the thickening and thinning of larynx that helps in voice modulation.

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