Armadillo
(Photo : Pexels / Brian Forsyth )

While hearing is a vital survival skill for animals, not every animal can hear and not every animal has ears of their own.

Why Some Animals Can't Hear

A-Z Animals reports that animals could become deaf due to trauma or illness. Dogs or cats, for instance, can become deaf. Their deafness could also be bilateral or unilateral.

Congenital deafness could also be another explanation. This means that some animals were just born deaf. In fact, the MSD Veterinary Manual notes that congenital deafness has been observed in over a hundred dog breeds.

Other animals, on the other hand, do not have the biological sense of hearing. This means that it is normal for them and their bodies to function fully or nearly deaf.

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Deaf Animals and How They Survive

There are some animals that are considered nearly deaf or fully deaf. These creatures have unique ways of surviving even with limited or no hearing at all.

Armadillos

These placental mammals are known for their armored shells. They typically span 30 inches in length, with their tail included. A-Z Animals explains that the biggest armadillo is known as the giant armadillo; it can reach 59 inches in length. The smallest one, the pink fairy armadillo, spans just five to six inches in length.

According to the Wildlife Informer, armadillos lack both eyesight and hearing, though research has shown that they are not fully deaf. Nevertheless, because of this, they use their sense of smell to navigate around their surroundings. They smell out their food, including cockroaches, earthworms, spiders, scorpions, and snails. Their armor, on the other hand, helps protect them against predators.

These creatures are also agile runners; they can run at 30 mph. They are also remarkable swimmers who can walk underwater.

Naked Mole Rat

Also known as sand puppies, naked mole rats are the only thermoconformer animals. They are almost fully cold-blooded. These creatures are also recognized as eusocial mammals. Because of such traits, they can survive and adapt to harsh conditions.

These creatures are also known to have a poor sense of hearing. The Wildlife Informer explains that their outer hair cells are incapable of amplifying sounds. They find it hard to pick up quiet sounds; they can only detect sounds that range from 0.5 to 4 kilohertz.

Aside from having these hearing difficulties, naked mole rats are also blind. Nevertheless, because their colonies comprise hundreds of them, they utilize their great numbers to find food and protect their underground tunnels.

Cephalopods

Squids, octopuses, and cuttlefish all fall under the cephalopod category. They are unique due to their bilateral symmetry, prominent heads, and tentacle and arm sets. While some of them are tiny, some can span over 45 feet.

These creatures were once thought to be fully deaf. However, they were later found to pick up low-frequency sounds. A-Z Animals explains that these creatures make use of statocysts to pick up sounds under the water. These statocysts are balanced sensory receptors that contain sac structures with statoliths and setae.

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