Skip to comments.Mystery Of Mammalian Ears Solved (Motorized Ears Give Mammals Acoustic Acuity)
Posted on 08/06/2007 3:25:38 PM PDT by GodGunsGuts
The long-standing argument centers around outer hair cells, which are rod-shaped cells that respond to sound waves. Located in the fluid-filled part of the inner ear called the cochlea, these outer hair cells sport tufts of hair-like cilia that project into the fluid. The presence of outer hair cells makes mammalian hearing more than 100 times better than it would be if the cells were absent.
As sound waves race into the inner ear at hundreds of miles per hour, their energy--although dissipated by the cochlear fluid--generates waves in the fluid, somewhat like the tiny waves made by a pebble thrown into a pond. This energy causes the hair cell cilia in both mammals and non-mammals to swing back and forth quickly in a steady rhythm.
In mammals, the rod-shaped body of the outer hair cell contracts and then vibrates in response to the sound waves, amplifying the sound. In a previous study, Zuo and his colleagues showed that a protein called prestin is the motor in mammalian outer hair cells triggers this contraction....
"If somatic motility is the dominant force for amplifying sound in mammals, this would mean that prestin is the reason mammals amplify sound so efficiently," Zuo said.
The researchers concluded that somatic motility was not simply a way to make cilia do their job better; rather, there is no connection between the hair cell contractions and how the cilia do their job. Instead, somatic motility, generated by prestin, is the key to the superior hearing of mammals.
(Excerpt) Read more at sciencedaily.com ...
Uh, what about birds. They seem to have hearing at least as good as humans. What to they have, cilia made from feathers?
Oh my, overdosing on prestin.
Are you sure he’s a mammal? He looks more like a cartoon.
Wouldn’t be something if the media had the courage to report this discovery for what it is? Further testament to the majesty of God. Of course, they spin it for the evolutionists instead.
some did. see
Why did you PhotoShop Obama’s ears to be smaller?
LOL - otherwise they’d need a 36000 x 20000 jpg image...too much bandwidth.
Wow, articulate AND audible acuity!
Thanks for the ping!
Enjoy your ham sandwich! :^)
I lost another keyboard... LOL... Great answer.....
Subject: Arkansas Discovery
Last January the New Orleans Times Picayune reported that a Cajun amateur archeologist having dug to a depth of 10-meters found traces of copper wire dating back 100 years.... and came to the conclusion that their ancestors already had a telephone network more than 100-years ago.
Not to be outdone by the Cajuns, in the weeks that followed, Texan scientists dug to a depth of 20-meters. Shortly after, headlines in the Dallas Morning News read: “Texas archaeologists have found traces of 200-year old copper wire, and have concluded that their ancestors already had an advanced high-tech communications network one hundred years earlier than the Cajuns.”
One week later, The Arkansas Times reported the following: “After digging as deep as 30-meters in the hills near Little Rock, Bubba Williams, a self taught archeologist, reported that he found absolutely nothing. Bubba has therefore concluded that 300-years ago the Arkansans were already using cell phones.”
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