Roosters are loud! They can hit volumes as high as 140 decibels which is the level of sound on an aircraft carrier deck. For humans, a noise above 120 decibels, about the level of a chainsaw, can cause permanent hearing damage. So you may wonder why roosters don’t go deaf.
Belgian researchers writing in the journal Zoology have the answer. They examined the skull structure of the birds. The researchers found that they have a built-in defense against loud sounds in the form of a sound barrier. When a rooster adjusts its head and neck to crow, small flaps of tissue close the ear canal. They effectively act as earplugs to dampens the noise significantly.
On top of that, the study reveals that roosters can regenerate the tiny hair cells deep within the ear that can become damaged by loud noises. Humans can’t do that, which is why deafness caused by loud sounds is permanent for us. For roosters, a degree of deafness would likely only be temporary if it happened at all.
“Micro-CT scans of a rooster and chicken head show that in roosters the auditory canal closes when the beak is opened,” the researchers wrote. “In hens the diameter of the auditory canal only narrows but does not close completely. A morphological difference between the sexes in shape of a bursa-like slit which occurs in the outer ear canal causes the outer ear canal to close in roosters but not in hens.”
So now you know why roosters don’t go deaf. God’s design in every living thing on Earth shows wisdom and an exceptional understanding of the problems that each species faces. The more we learn about the creation, the more we understand the wisdom and creative nature of God. “We can know there is a God through the things He has made” (Romans 1:19-20).
–John N. Clayton © 2018
You can read more about the research by clicking HERE.