Text written in Basque and translated automatically by Elia without any subsequent editing. SEE ORIGINAL

Photo of the week: Elephant ears

Elephants, both Asian and African, can communicate at distances of up to 5 km through airborne sounds. But they have another way of sending signals: low-frequency seismic waves that travel through the earth. The vibrations are transmitted from the ground to the elephant's legs and finally reach their inner ear directly from the elephant's skull. In this way, they communicate with each other at a distance of 10 km or more.

A study published in the journal Frontiers in Audiology and Otology has found that this fine and peculiar hearing may be due to the size of the bones and a special muscle.

“Elephants can have the ability to voluntarily close their auditory pathways and, just as we hear louder the sounds we create with headphones or plugs, they can hear louder terrestrial vibrations.”

The ear of these terrestrial animals can adopt different configurations, depending on which we can hear sounds of certain frequencies. The ear of small rodents, for example, is ideal for hearing high-frequency sounds. The ears of larger mammals, on the other hand, are ideal for listening to low-love sounds. Within this range, there is a great diversity in the shape and size of eardrums and bones.

The researchers conclude that elephants, for anatomical reasons, have a high sensitivity to low-frequency sounds. Asian and African elephants have the largest central ears of all terrestrial vertebrates, as well as the lowest hearing frequency range. Their middle ear bones are nine times heavier than humans, and their eardrum is seven times larger. However, their ratio to body size does not vary much. This means that the middle ear of elephants does not have a specialized structure; it is simply large, and the authors believe that this may be useful for hearing low-frequency sounds.

On the other hand, the authors believe that elephants may have another curious ability: the ability to voluntarily close the auditory pathways. When we put on headphones or earplugs, we close the auditory pathways and listen louder to the sounds we produce, such as chewing or breathing. Researchers believe that elephants with a contracted special muscle can have the ability to close the auditory pathways, allowing them to better perceive those sounds they receive from the ground by vibration. Researchers estimate that by closing the auditory vessels, elephants can hear low-frequency sounds 30 times better.