Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Rare Chinese frogs communicate by means of ultrasonic sound

16.03.2006


Artist’s rendering of Amolops tormotus courtesy of Margaret Kowalczyk.


First came word that a rare frog (Amolops tormotus) in China sings like a bird, then that the species produces very high-pitch ultrasonic sounds. Now scientists say that these concave-eared torrent frogs also hear and respond to the sounds.

The findings, to appear in the March 16 issue of Nature, represent the first documented case of an amphibian being able to communicate like bats, whales and dolphins, said corresponding author Albert S. Feng, a professor of molecular and integrative physiology at the University of Illinois at Urbana-Champaign.

Feng, a researcher at the Beckman Institute for Advanced Science and Technology, was introduced to the frog species by Kraig Adler, a Cornell University biologist who had learned about it while conducting a survey of amphibians in China. Feng continues to study frogs and bats to understand how the brain processes sound patterns, especially in sound-cluttered environments in which filtering is required to allow for communication.



Feng and colleagues previously reported that males of the species make these high-pitched bird-like calls, with numerous variants in terms of harmonics and frequency sweeps. Some sounds exceeded their recording device’s maximum capability of 128 kilohertz. Human ears hear sound waves generally no higher than 20 kilohertz. The frogs studied inhabit Huangshan Hot Springs, a popular scenic mountainous area, alive with noisy waterfalls and wildlife west of Shanghai.

"Nature has a way of evolving mechanisms to facilitate communication in very adverse situations," Feng said. "One of the ways is to shift the frequencies beyond the spectrum of the background noise. Mammals such as bats, whales and dolphins do this, and use ultrasound for their sonar system and communication. Frogs were never taken into consideration for being able to do this."

Adler had drawn attention to the species because the frogs do not have external eardrums, raising the possibility of unusual hearing abilities. "Now we are getting a better understanding of why their ear drums are recessed," Feng said. "Thin eardrums are needed for detection of ultrasound. Recessed ears shorten the path between eardrums and the ear, enabling the transmission of ultrasound to the ears."

To test if the frogs actually communicated with their ultrasonic sounds, Feng and colleagues returned to China with their recording equipment and a special device that allowed playback of recorded frog calls in the audible or ultrasonic ranges. They observed eight male frogs under three experimental conditions (no sounds, playback of calls containing only audible parts and playback of just ultrasonic frog calls).

During playback, the researchers watched for evoked calling activity in which a male frog begins calling upon hearing calls from other frogs in the area. Six frogs responded to ultrasonic and audible sound ranges, with four responding with calls in both ranges. One frog called 18 times to ultrasonic calls, including four very telling rapid responses, Feng said. Another frog did not respond to ultrasonic stimulation but produced calls 18 times to an audible prompt.

Clearly, Feng said, some of the frogs indeed communicated ultrasonically. They have the ability to do so, but for some reason some frogs do and some don’t, he said. "We believe that all of them have the capacity to respond to the ultrasound."

Ultrasonic communication likely will be found in other amphibians and birds, Feng said, but, until now, no one has bothered to look into it.

"Humans have always been fascinated by how some animals can discern their world through a sensing system vastly different from our own," Feng said. "The electromagnetic sense in fishes and homing pigeons, polarized light vision in ants, chemical sensing of pheromones in insects and rodents, echolocation by ultrasound in bats and dolphins, are just a few examples.

"That frogs can communicate with ultrasound adds to that list and represents a novel finding, because we normally think such ability is limited to animals equipped with a sophisticated sonar system," he said. "This suggests that there are likely many other examples of unexpected forms of communication out there."

Jim Barlow | EurekAlert!
Further information:
http://www.uiuc.edu

More articles from Life Sciences:

nachricht Water forms 'spine of hydration' around DNA, group finds
26.05.2017 | Cornell University

nachricht How herpesviruses win the footrace against the immune system
26.05.2017 | Helmholtz-Zentrum für Infektionsforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

How herpesviruses win the footrace against the immune system

26.05.2017 | Life Sciences

Water forms 'spine of hydration' around DNA, group finds

26.05.2017 | Life Sciences

First Juno science results supported by University of Leicester's Jupiter 'forecast'

26.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>