Ear coils enhance bass, according to reports in news@nature, 13 Mar 2006 and New Scientist 18 Mar 2006, p20. The cochlea, or inner ear, is the part of the ear that converts sound to electrical signals to be sent to the brain. It consists of a fluid filled tube that is coiled like a snail shell. Biologists have assumed that it had this shape simply to save space, but a new study of how sound is transmitted through the cochlea shows that the curved shape makes sound energy build up towards to the outer wall of the spiral the further into the curve it goes. This effectively amplifies the sound by 20 decibels at the end of the spiral, where the lowest frequencies are detected. The effect is like that of “whispering galleries” where sounds are concentrated around the walls of cylindrical spaces, such as in St Paul’s Cathedral.

Philip Ball of news@nature writes; “If the researchers are right, then the ear is more sophisticated than we thought.” Karl Grosh, an ear researcher at University of Michigan, Ann Arbor commented: “It would show we need to take a step back from the cell biology and see how the cochlea works as an integrated system.” Scientists hope this study will help in the design of better cochlear implants (“bionic ears”) for deaf people.

Editorial Comment: Finding out that ear is more sophisticated than we thought is a challenge to those who believe that it came about by chance random processes. Integrated systems only work because someone outside the system has a purpose for the system and can put together the component parts in the best way to achieve that purpose. If scientists do copy the sound enhancing property of the cochlea and put it to use in ear implants they will have only added to the evidence that the ear is the product of plan and purpose, not chance random processes. (Ref. biotechnology, bioengineering, audition)

Evidence News 30th August 2006