Dolphin hearing system component found in insects

December 13, 2012

A hearing system component thought to be unique in toothed whales like dolphins has been discovered in insects, following research involving the University of Strathclyde.

The research is challenging ideas about how a large group of insects including crickets and katydids hear, revealing the unexpected similarity to toothed whale hearing.

Scientists from the School of Biological Sciences at The University of Auckland, with colleagues from Plant & Food Research in New Zealand, led the research with engineers from the University of Strathclyde working on the biomechanical aspects of the project.

They discovered that the iconic New Zealand insect, the weta, rely on a unique lipid - a compound that includes oils and fats - to hear the world around them.

Dr James Windmill, of the University of Strathclyde's Centre for Ultrasonic Engineering, said: "As engineers we are particularly interested in how sound interacts with certain materials and how it travels to and from a source. These findings help us to improve our fundamental knowledge and could inspire new systems in ultrasound technologies like biomedical and non-destructive testing.

"The discovery is interesting as previously only toothed whales were known to use this hearing system component, the lipid. There are many similarities in the use of lipids to amplify the sounds and help both animal groups to hear.

"We don't know why animals who are so far apart in evolutionary terms have this similarity, but it opens up the possibility that others may use the same system component."

The sound is known to be transmitted through a liquid-filled cavity to reach the hearing organs, but until the current research was carried out it was presumed that the liquid was simply the insect equivalent of blood.

The researchers found that it was in fact a lipid of a new chemical class. They believe the role of the lipid is to efficiently transmit sound between compartments of the ear, and perhaps to help amplify quiet sounds.

Dr Kate Lomas from the University of Auckland, said: "In the weta, as in other members of the Ensiferan group which includes katydids and crickets, sound is detected by ear drums on the front legs."

Using new tissue analysis and three-dimensional imaging techniques the scientists also discovered a tiny organ in the insects' ears, which they named the olivarius after Dr Lomas' son Ollie. The organ appears to be responsible for producing the all-important lipid.

It may have been overlooked in previous studies because standard analytical techniques, which are much harsher, would have damaged or destroyed the fragile tissue.

Dr Lomas added: "The ear is surprisingly delicate so we had to modify how we looked at its structure and in doing so we discovered this tiny organ."

The researchers carried out their work with the Auckland tree weta. They believe that the same method of hearing is likely to be used by other members of its biologic class, including crickets and katydids, which are famous for the sounds they produce.
-end-
The researched has been published in the PLOS journal - available online at: http://dx.plos.org/10.1371/journal.pone.0051486

University of Strathclyde

Related Hearing Articles from Brightsurf:

Two molecular handshakes for hearing
Scientists have mapped and simulated those filaments at the atomic level, a discovery that shed lights on how the inner ear works and that could help researchers learn more about how and why people lose the ability to hear.

Proof-of-concept for a new ultra-low-cost hearing aid for age-related hearing loss
A new ultra-affordable and accessible hearing aid made from open-source electronics could soon be available worldwide, according to a study published September 23, 2020 in the open-access journal PLOS ONE by Soham Sinha from the Georgia Institute of Technology, Georgia, US, and colleagues.

Ultra-low-cost hearing aid could address age-related hearing loss worldwide
Using a device that could be built with a dollar's worth of open-source parts and a 3D-printed case, researchers want to help the hundreds of millions of older people worldwide who can't afford existing hearing aids to address their age-related hearing loss.

A promise to restore hearing
For the first time, researchers have used base editing to restore partial hearing to mice with a recessive mutation in the gene TMC1 that causes complete deafness, the first successful example of genome editing to fix a recessive disease-causing mutation.

Surprising hearing talents in cormorants
The great cormorant has more sensitive hearing under water than in air.

Veterinarians: Dogs, too, can experience hearing loss
Just like humans, dogs are sometimes born with impaired hearing or experience hearing loss as a result of disease, inflammation, aging or exposure to noise.

Older people who use hearing aids still report hearing challenges
A high proportion of older people with hearing aids, especially those with lower incomes, report having trouble hearing and difficulty accessing hearing care services, according to a study from researchers at Johns Hopkins Bloomberg School of Public Health.

Hearing class
New study finds that the class of neurons responsible for transmitting information from the inner ear to the brain is composed of three molecularly distinct subtypes.

Hearing tests on wild whales
Scientists published the first hearing tests on a wild population of healthy marine mammals.

Genes critical for hearing identified
Fifty-two previously unidentified genes that are critical for hearing have been found by testing over 3,000 mouse genes.

Read More: Hearing News and Hearing Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.