Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Locusts’ Built-In ‘Surface Analysis’ Ability Directs Them to Fly Overland

12.08.2005


Closeup of locust in tree. (Photo by Asaph Rivlin)


Swarms of millions of locusts have, since Biblical times and until our very own day, been considered a “plague” of major proportions, with the creatures destroying every growing thing in their path.

Until now, it was thought that the directions of these swarms were predominantly directed by prevailing winds. Now, Hebrew University of Jerusalem scientists have shown that a physiological trait of these grasshoppers – namely their polarization vision -- provides them with a built-in source of “surface analysis” – a discovery that could pave the way for efforts to effectively combat this periodic scourge by controlling their natural inclination to fly over land rather than water.

The desert locusts, known scientifically as Schistocerca gregaria, are able to swarm for great distances and in numbers measuring in the millions. During the locust invasion of November 2004 in Israel, it appeared that a swarm came in an easterly direction over Sinai up to the Gulf of Eilat, then turned northward without crossing the water. Only when the swarm reached the northern tip of the gulf did some of them turn again east in the direction of Aqaba and other areas of Jordan, as well as straight north over southern Israel.



This observation led to examination by scientists of the Hebrew University of Jerusalem Department of Evolution, Systematics and Ecology and the Interuniversity Institute for Marine Sciences in Eilat to examine how the locusts were able to identify the gulf water and knew not to fly over it. The research focused on the ability of the locusts to identify polarized light. This is a trait which is lacking in humans but exists among other species, such as fish and insects.

The research was conducted by Dr. Nadav Shashar, who is considered a leading world expert on polarized sight, working with two students, Shai Sabah and Noa Aharoni. The research was published in a recent issue of the journal of the British Royal Society, Biology Letters, as well as in the science news sections of the journals Science and Nature.

“In order to examine if the locusts are using polarized light in determining their flight path, we examined individual locusts’ reactions in situations in which polarized and non-polarized light was reflected from various surfaces. We were able to prove that the locusts avoided flying over areas which were reflecting polarized light -- for example from mirrors or plastic surfaces.”

The sea reflects polarized light much more than dry land (which reflects mainly diffused, non-polarized light), enabling a distinction to be made between the two.

“When the locusts are presented with a situation of choice between surfaces reflecting either polarized or diffused light, they exercise their preference to fly over the (dry land) area of diffused light,” said Dr. Shashar. This is a survival instinct, since if they flew over a body of water, the locusts would be deprived of both nourishment and a place to land and rest.

This research, said Dr. Shashar, could be important in providing information that would be useful in developing means for “deceiving” the locusts and deterring them from flying over agricultural lands and causing the great damage that ensues.

One way of doing so might be through more extensive use of plastic sheeting as shields to create the reflection of the polarized light that the locusts avoid.

Jerry Barach | alfa
Further information:
http://www.huji.ac.il

More articles from Ecology, The Environment and Conservation:

nachricht Successful calculation of human and natural influence on cloud formation
04.11.2016 | Goethe-Universität Frankfurt am Main

nachricht Invasive Insects Cost the World Billions Per Year
04.10.2016 | University of Adelaide

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>