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 Rainbow colors reveal cell history: Uncovering β-cell heterogeneity
22.09.2017 | DFG-Forschungszentrum für Regenerative Therapien TU Dresden

nachricht The pyrenoid is a carbon-fixing liquid droplet
22.09.2017 | Max-Planck-Institut für Biochemie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Rainbow colors reveal cell history: Uncovering β-cell heterogeneity

22.09.2017 | Life Sciences

Penn first in world to treat patient with new radiation technology

22.09.2017 | Medical Engineering

Calculating quietness

22.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>