A turtle drawing, with a simple question scrawled at the bottom, “Where are the turtle ears?” made its way to my desk the other day. The drawing, sketched by a young child, showed the turtle with no ears. The child asked me “How does he hear?”
In fact, turtles do have ears, which are actually small holes in the sides of their heads, allowing sound waves to enter.
In the past, people thought that turtles were deaf. This presumption may most likely have arisen from the fact that turtles do not have visible or physical ears that stick out from the sides of their heads, as is the case with most animals.
Even though turtles do not have these visible pair of external ears, they can, nevertheless, discern sounds, and “hear.” They do not hear as acutely as we humans, but they do have the necessary auditory nerve and corresponding brain center required for them to feel and decipher surrounding vibrations. Sound waves are gathered via the small external holes found on the side of the turtle’s head, and transmitted via the middle ear, which is well designed to increase the volume of the sound waves. Thus, although scientists feel that turtles rely more heavily on their senses of vision and smell, which are much more highly developed, they are definitely capable of hearing.
As the anatomical make-up of each animal has a corresponding physiological function, the reason that the ears of turtles are located inside their heads is so they are more aero-dynamic whenever they are in water. This would allow them to detect sounds and vibrations in their surroundings.
Although turtles do not have tympanum or ear drums that gather sound waves for a more defined hearing, turtles are capable of detecting low-frequency sounds and sensing vibrations, whether they are in the water or on land.
Because of this, they rely mostly on their vision and sense of smell to help them move around. There are even theories suggesting that the refined sense of smell in turtles allows them to return to the exact beach on which they originally hatched in order to mate and lay their eggs.
It is known that turtles find or identify food, mates, and territory by their sense of smell. The vision of turtles is also excellent. They can differentiate between colors and shapes, things that are crucial to animals that live or spend time in water. What turtles lack in a refined sense of hearing, they make up for in their sense of smell and their excellent vision.
Some people consider their pets just as important as their children. Whether true or not, some turtle owners imagine their beloved pets are able to recognize and respond to their voices!
We have no objective data to prove or disprove this theory. The way a turtle responds may, as some experts claim, come from the way they sense vibrations around them. Probably it is not as much the sound or distinctive quality of the voice via the turtle’s ears, but the vibrations coming from closing doors and other vibration-inducing motions or stimulations around them. Let’s hope that future research will help us determine the truth about turtle ears!