Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Reptile vocalization is surprisingly flexible

30.05.2017

It has now been shown for the first time that non-avian reptiles are able to adjust their calls in relation to environmental noise as is known for the complex vocal communication systems of birds and mammals. In Tokays, night active geckos, researchers of the Max Planck Institute for Ornithology in Seewiesen found an increase in the duration of brief call notes in the presence of broadcast noise compared to quiet conditions. The geckos did not adjust the amplitude of their calls, however, under noisy conditions the animals produced more of the louder syllables. This discovery shows that the communication systems of non-avian reptiles are much more complex than previously thought.

The sophisticated vocal communication systems of birds and mammals are characterized by a high degree of plasticity in which signals are individually adjusted in response to changes in the environment. One mechanism of such vocal plasticity is the Lombard effect, in which the call amplitude increases depending on the level of ambient noise. This Lombard effect is often accompanied by an increase in the duration of the call, which further helps to detect the signals in noise.


Phenotypic plasticity of Tokay calls reveals the complex communication of lizards

Frank Lehmann / Max Planck Institute for Ornithology

In non-avian reptiles some species do have vocal communication, like for example the Tokay, a night active gecko from South East Asia. Within his repertoire, especially the loud GECK-O call stands out and led to his scientific name Gekko gecko. The GECK-O call has important functions for the communication of Tokay males to attract females and to repel rival males.

This call is often preceded by low-amplitude cackles. For their study, Henrik Brumm and Sue Anne Zollinger of the Max Planck Institute for Ornithology exposed Tokays to noise of about 65 dB(A) which corresponds to the traffic noise of a busy street.

They wanted to find out if the Lombard effect could also be found in a reptile. And in fact, the Tokays increased the duration of the GECK-calls by 7 percent and the O-calls by 37 percent compared to the control group in quiet conditions. Therefore, the Tokays, and probably also other vocally-communicating reptiles, are able to adjust their calls depending on the ambient conditions.

However, the researchers could not find a Lombard effect in the calls, as the Tokays did not increase the amplitude of their call syllables in relation to the background noise level. „The study suggests that the Lombard effect evolved independently in birds and mammals“, says Henrik Brumm, first author of the study and research group leader in Seewiesen.

However, the Tokays employed another strategy to increase the overall signal-to-noise ratio of their calls: Instead of increasing the amplitude of each call component, they produced more of the loud GECK-O syllables and fewer of the softer cackle calls in noise. „We think that the fact that signals will reach the intended recipient is a driving force for the evolution of a communication system, independently of the animal group“, says Sue Anne Zollinger, co-author of the study.

Contact:
Dr. Henrik Brumm
Max Planck Institute for Ornithology, Seewiesen
Research Group Leader „Communication and Social Behaviour”
Phone.: +49 8157 932 355
E-Mail: brumm@orn.mpg.de

Dr. Sabine Spehn | Max-Planck-Institut für Ornithologie

More articles from Life Sciences:

nachricht NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation

nachricht Pollen taxi for bacteria
18.07.2018 | Technische Universität München

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

NYSCF researchers develop novel bioengineering technique for personalized bone grafts

18.07.2018 | Life Sciences

Machine-learning predicted a superhard and high-energy-density tungsten nitride

18.07.2018 | Materials Sciences

Why might reading make myopic?

18.07.2018 | Health and Medicine

VideoLinks
Science & Research
Overview of more VideoLinks >>>