How do birds hear?
Having the ability which no other animal possesses makes birds a very different and unique creature. When they fly, they go into a dimension to which there is no reach for other animals. Similarly, as they have evolved by the time to fly, they have developed some other exciting factors, some of which we have discussed earlier. Today we are looking forward to learning about the hearing abilities of the birds. We all know that they are amazing flyers and have efficient respiratory systems, but what about hearing? So How do birds hear?
Birds listen to sounds through their ears as all other vertebrates do. Their feathers usually hide Their ears. The external ears of birds are like holes that are present on both sides of their head. You can observe these holes (ears) caressing them, and sometimes when the wind blows, the airs are visible, and you may notice them. They are also visible during their self-grooming sessions.
You may have noticed owls feathers are present in the form of discs. They are not illogically present; instead, they reflect sound in the ears of the owl in a better way, the phenomenon is parabolic reflection.besides, their ears are also present in a pattern with one a bit higher from the other. A species of owls called barn owls can hear the footsteps of a mouse at the ground from a considerable distance and can capture them even if they are blind. Woah! So you see how interesting it is to learn about how do birds hear?
Bird senses and how they use them?
Like humans, birds also have all the five senses to see, hear, touch, smell, and feel. But these are not like ours; they are very well developed so that different birds can survive in different environments. However, to what extent each sense is beneficial is strongly related to the species of the bird. However, today we are concerned mainly with the feeling of hearing. How do birds hear?
Birds Sense to hear:
After the sight, to hear is the second most important sense of the birds. Their ears are positioned that they are present following the eyes and are slightly lower. In most birds, ears have the protection of feathers, and these feathers are known as auriculars. However, there are bald birds as well. On them, the ears as holes are visible.
Another important thing which affects the hearing is the “Size of the head”. As I have explained above, the discs of owls determine its shape and channel the sound towards their ears. Though birds’ hearing is limited to a very fewer frequency ranges than humans, they are very vigilant towards pitch, tone, and changes in rhythm. By uniquely configuring these variations, they can even identify different birds in a loud flock.
Apart from these, how do birds hear? They also identify different sound patterns and calls made by other birds. It is essential because they have to determine whether a call is a warning or a threat from a predator. It can also be called sharing food or mating as well. Therefore, by the time birds have adapted themselves to hear and listen to different calls to survive in the harsh wild environment.
Some birds also use a technique called “Echo-location,” which is also used by bats. The cave birds use this technique; they use particular clicks and chirps to identify their way through the wave because even sensitive vision won’t work there.
How do birds hear without ears?
First, to tell you, they do have ears, but they are not similar to ours. We human beings have an outer ear, and then a structure called an inner ear, but birds only have internal ears, which are also covered by feathers for protection. But it is incredible that even though they don’t have outer ears that are responsible for the direction of the sound, they still manage to locate the sound resource. So what’s the science behind this?
When a sound pattern strikes with the bird’s eardrums, the nearest ear drum further passes that sound at a higher frequency than the original, enabling the birds to identify the direction of music even though when the sound reaches both ears at the same time.
Moreover, the hearing process has a secure connection with the eyesight of the birds. We know that the eyes of the birds are present on the sides and not in the front. So, whenever a sound strikes the ear, eyes respond to the closest eardrum through which the sound is detected. After the sound confirmation, they use their 360-degree angle view for further locating the source efficiently.
The hearing of birds
The birds’ calls are crucial for them to listen for survival. But, how do birds hear those? Bird’s ear is also very similar to the mammalian ear, but they lack the external ear called the pinna, though owls do have them. We have three bones in our which vibrate and process the sound, but birds have only one bone known as the columella.
The sound hits the eardrum, and then it is passed to the columella and then to the cochlea. An interesting fact is that in humans, the ability to hear degenerates over time, but in birds, that is not the case. In birds, the hair cells in the ear continue to regenerate; thus, they can maintain hearing ability throughout the ear. if your are a bird lover definitely you want to know about How do birds get pregnant?
How do Birds Hear? What can birds hear?
As I told you very much about the question, How do birds hear? Now let’s see what they can hear? The length of cochlea varies in different species of birds. That means the capability of hearing different frequencies also varies. For example, the length of the cochlea in pigeons is 5mm, whereas in barn owls, it is 1 cm, so there are contradictions to it.
Larger cochlea ensures better sound quality, more sound receptors, and sensitivity to a vast range of frequencies. Most species of birds are sensitive to a narrow range of frequencies and can listen up to 1-4 kHz. However, some may be more sensitive to very low or high frequencies than this. Above 20 kHz (Ultrasound), the birds cannot hear or show sensitivity. Some of the pigeons have been observed to show sensitivity towards infrared (lower than 20Hz).
How do aquatic birds hear?
We have studied the terrestrial birds so far, and it’s easy for them to hear in the air. But what about aquatic birds? They have to dive deep into the water. How do they manage to listen in such depth? How do birds hear?
Many aquatic birds have developed many adaptations to survive in marine environments. Auks and murres have evolved a unique structure that shows up when they are diving and protects the internal ear by preventing water from flowing into the ear. Penguins can control their muscles while diving. King penguins also have a high vein structure; when they are filled in blood, they can control the water flow by regulating pressure. The same structure is also present in the outer ear, which prevents the water flow from that.
Do we hear what birds hear in the bird songs?
We have learned about How do birds hear? But can we say that what we listen to is similar to the listening of birds? The ornithology describes birdsongs based on tempo, pitch, and complexity. When humans speak, they already have learned protocols that are necessary for communication. Science has proved that birds also have magnificent structures for processing sounds and songs.
To us, different calls appear as songs, but in particular, they are code words or protocols for a specific purpose. Each song or call is learned over time and is used for a specific purpose. Birds are also able to process the requests from other birds as well. Calls may be an alert to a threat or a mating call or an invitation for sharing food.