Roar

Many mammals have evolved to produce roars and other roar-like vocals for purposes such as long-distance communication and intimidation.

The anatomical basis for the ability to roar often involves modifications to the larynx and hyoid bone and enlarged internal air spaces for low-frequency vocal resonation.

A larger larynx also has enlarged vocal cords which contributes to a deeper pitch and more massive folds leads to slower oscillation.

[1] Elephants possess a pharyngeal pouch associated with their larynx and hyoid apparatus, and their roars can also be modified by the nostrils in their trunks.

The snow leopard also has this property, but cannot roar, as its shorter vocal folds provide little resistance to airflow.

[1] For example, in gorillas only the adult male (silverback) has a larynx large enough and vocal cords lengthened enough to produce a full roar.

In lions, where both sexes roar, the vocalization plays a role in social spacing and territorial defense.