Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Sex-pheromone link to insect evolution

11.09.2002


Cornell University entomologists have unlocked an evolutionary secret to how insects evolve into new species. The discovery has major implications for the control of insect populations through disruption of mating, suggesting that over time current eradication methods could become ineffective, similar to the way insects develop pesticide resistance.



The researchers, led by Wendell L. Roelofs, the Liberty Hyde Bailey Professor of Insect Biochemistry at Cornell, made the discovery while examining ways to keep European corn borers from mating, multiplying and then chewing up farmers’ fields. They discovered the existence of a previously undetected gene, the delta-14, that can regulate the attractant chemicals produced in sex-pheromone glands of female borers. The gene can be suddenly switched on, changing the pheromone components that females use to attract males for mating.

The entomologists have demonstrated that insects evolve chemical systems in leaps rather than in minute stages, as had been previously assumed. The researchers also discovered that there are rare males in the corn borer population -- about 1 in 200 -- capable of responding to chemicals produced by the delta-14 gene.


"This is one way that insects become new species," says Roelofs, whose paper, "Evolution of moth sex pheromones via ancestral genes," will be published on the web site of the Proceedings of the National Academy of Science (Sept. 9-15, 2002.) The Cornell co-authors on the paper are: Weitian Liu, research associate in entomology; Guixia Hao, postdoctoral researcher in entomology; Hongmei Jiao, laboratory technician in entomology; and Charles E. Linn Jr., senior research associate in entomology. Alejandro P. Rooney, Mississippi State University assistant professor in biological sciences also contributed to the paper. The research was funded by the National Science Foundation and will continue to be funded by the U.S. Department of Agriculture’s National Research Initiative.Roelofs explains that female insects attract males with specialized pheromones that he compares to radio frequencies. At major events with thousands of people, for instance, police might communicate on channel one, emergency medical personnel on channel two and administrators on channel three.

"With male and female borers, it’s the same thing," says Roelofs. "Certain species communicate on channel one, others on channel two, others on channel three. But when a female has a mutated delta-14 gene -- and by mutated I mean the gene is turned on -- it changes her channel from three to five. That means that out of 200 male borers, 199 cannot respond to her. It’s the one male borer capable of responding to her very selective channel that sets out to mate."

Soon other females with the delta-14 gene mate with other rare respondent males. Eventually, over time, the males and females stabilize their pheromone communication system, essentially isolating this new population from the parent species. "That’s one way species evolve," Roelofs says.

Manipulation of insect chemistry is an effective pest control strategy in that it can be used to disrupt mating behavior. For more than 20 years, Roelofs’ research at Cornell’s New York State Agricultural Experiment Station in Geneva has focused on chemical analyses of the pheromone components. Agricultural researchers have identified pheromones in over 1,000 species of insects and use them to monitor pest populations in 250 species and to disrupt mating in more than 20 species, Roelofs says.

This new research has implications for pest control. In addition to explaining how pheromone evolution might have occurred in the past, the paper also demonstrates that the conditions required for dramatic shifts in pheromone blends could well be present today and in the future. Insect populations could be capable of shifting away from a pheromone blend being used for their control in the field, making such control ineffective.

"Based on the difficulty of generating even small changes in pheromone blends in the lab, we thought that such resistance could not develop because natural pressure would prevent the species from gradually shifting to a different blend," says Roelofs. The presence of this kind of gene, capable of sudden activation, might provide a mechanism for resistance to occur, although no evidence for this has been found so far, he notes.

Roelofs expects this discovery to stimulate more research in this area, specifically to determine the breadth of the phenomenon and how it affects the evolution of many insect communication systems. His research team will be working on the genomes of fruit flies, mosquitoes, crickets and silkworms to detect if these kinds of genes are present.

Blaine P. Friedlander, Jr. | Cornell University News Service

More articles from Life Sciences:

nachricht Meadows beat out shrubs when it comes to storing carbon
23.11.2017 | Norwegian University of Science and Technology

nachricht Migrating Cells: Folds in the cell membrane supply material for necessary blebs
23.11.2017 | Westfälische Wilhelms-Universität Münster

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Frictional Heat Powers Hydrothermal Activity on Enceladus

Computer simulation shows how the icy moon heats water in a porous rock core

Heat from the friction of rocks caused by tidal forces could be the “engine” for the hydrothermal activity on Saturn's moon Enceladus. This presupposes that...

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Underwater acoustic localization of marine mammals and vehicles

23.11.2017 | Information Technology

Enhancing the quantum sensing capabilities of diamond

23.11.2017 | Physics and Astronomy

Meadows beat out shrubs when it comes to storing carbon

23.11.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>