Featured Research

from universities, journals, and other organizations

Ultrasonic sounds of the rainforest

Date:
April 5, 2013
Source:
University of Lincoln
Summary:
Research aimed at developing ultrasonic microphones with insect-like sensitivity is to continue in the rainforests of Colombia and Ecuador.

Research aimed at developing ultrasonic microphones with insect-like sensitivity is to continue in the rainforests of Colombia and Ecuador.

Following the discovery of a previously unidentified hearing organ in the South American bushcrickets' ear, a scientist from the University of Lincoln (UK) will now study the role of this Auditory Vesicle in hearing sensitivity.

Dr Fernando Montealegre-Zapata, from the University's School of Life Sciences, aims to understand how bushcrickets or katydids pick up on ultrasonic frequencies in their natural environment. The insects communicate using the highest-pitched calls in nature (130-150 kHz), which are not detected by humans. The male produces sound by rubbing its wings to attract distant females.

He said: "This animal can detect ultrasonic signals even at long distances. The problem is that at such high frequencies the sound travels in very short wavelengths which get diffracted, meaning the sound gets weaker as more obstacles are in the dispersive path. However, the bushcricket's small ear is still able to detect this fading ultrasonic energy at long distances. I want to test how the bushcrickets manage to do that in a field environment. The fluid in the katydid 'cochlea', which I named the Auditory Vesicle, is the key element in the hearing process. We want to investigate why this is the case and the first step is testing its sensitivity in their natural environment and revealing the chemical composition."

In mammals, hearing relies on three stages: an eardrum collecting sound, a middle ear impedance converter and a cochlear frequency analyser. Dr Montealegre-Zapata recently demonstrated that the bushcricket's ear performs these steps in the hearing process, something previously unknown in insects.

The calls of the bushcricket are theoretically not suited for long-range attraction, as ultrasound suffers excess attenuation in rainforest environments. Therefore, the insect's ears must have evolved to achieve sufficient sensitivity at such frequencies.

Dr Montealegre-Zapata said: "I want to find out how these insects mitigate the effects of sound degradation and how the female ear is structurally and functionally organised to detect distant calling males. The small ear will be used as a biological microphone to detect the sensitivity and hearing range of the female. In the future we want to produce microphones that work like this."

The ears of these ultrasonic insects are extremely sensitive and have a clear size and sensitivity ratio advantage over equally responsive microphones.

In particular, condenser microphones (used in hearing research, plus the automotive and music industries) are expensive, mechanically fragile, susceptible to humidity and not very sensitive.

By constructing network analogues between mechanical (insect) and electrical (microphone) systems, this project can advance research into the design and construction of ultrasensitive microphones with unusual broad frequency responses.


Story Source:

The above story is based on materials provided by University of Lincoln. Note: Materials may be edited for content and length.


Cite This Page:

University of Lincoln. "Ultrasonic sounds of the rainforest." ScienceDaily. ScienceDaily, 5 April 2013. <www.sciencedaily.com/releases/2013/04/130405082548.htm>.
University of Lincoln. (2013, April 5). Ultrasonic sounds of the rainforest. ScienceDaily. Retrieved September 17, 2014 from www.sciencedaily.com/releases/2013/04/130405082548.htm
University of Lincoln. "Ultrasonic sounds of the rainforest." ScienceDaily. www.sciencedaily.com/releases/2013/04/130405082548.htm (accessed September 17, 2014).

Share This



More Plants & Animals News

Wednesday, September 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Some Tobacco Farmers Thrive Amid Challenges

Some Tobacco Farmers Thrive Amid Challenges

AP (Sep. 16, 2014) The South's tobacco country is surviving, and even thriving in some cases, as demand overseas keeps growers in the fields of one of America's oldest cash crops. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Scientists Given Rare Glimpse of 350-Kilo Colossal Squid

Scientists Given Rare Glimpse of 350-Kilo Colossal Squid

AFP (Sep. 16, 2014) Scientists say a female colossal squid weighing an estimated 350 kilograms (770 lbs) and thought to be only the second intact specimen ever found was carrying eggs when discovered in the Antarctic. Duration: 00:47 Video provided by AFP
Powered by NewsLook.com
Raw: Scientists Examine Colossal Squid

Raw: Scientists Examine Colossal Squid

AP (Sep. 16, 2014) Squid experts in New Zealand thawed and examined an unusual catch on Tuesday: a colossal squid. It was captured in Antarctica's remote Ross Sea in December last year and has been frozen for eight months. (Sept. 16) Video provided by AP
Powered by NewsLook.com
Ivorians Abandon Monkey Pets in Fear Over Ebola Virus

Ivorians Abandon Monkey Pets in Fear Over Ebola Virus

AFP (Sep. 16, 2014) Since the arrival of Ebola in Ivory Coast, Ivorians have been abandoning their pets, particularly monkeys, in the fear that they may transmit the virus. Duration: 00:47 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

    Technology News



    Save/Print:
    Share:

    Free Subscriptions


    Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

    Get Social & Mobile


    Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

    Have Feedback?


    Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
    Mobile: iPhone Android Web
    Follow: Facebook Twitter Google+
    Subscribe: RSS Feeds Email Newsletters
    Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins