Cicadas have their hearing organs in their stomachs.
Crickets have their hearing organs in their knees.
Male mosquitoes hear with thousands of tiny hairs growing on their antennae.
Fish do not have ears but they can hear. They hear pressure changes through ridges on their bodies.
Snakes do not have ears, but their tongues are sensitive to sound vibrations.
In World War One (WWI) parrots were kept on the Eiffel Tower in Paris, France because of their remarkable sense of hearing. When the Parrots heard the enemy aircraft coming they would warn everyone of the approaching danger long before any human ear would hear it.