If a specific butterfly anti-sex scent is coupled with a pleasant experience, then parasitic wasps are able to develop long-term memory and respond to this scent that they do not instinctively recognize.
After successfully ‘hitch-hiking’ with a mated female cabbage white butterfly and parasitizing her eggs, the parasitic wasps are able to remember the route and navigate it again. Researchers from Wageningen University, Netherlands, reported this finding in this week’s Proceedings of the National Academy of Sciences.
Research in Wageningen has shown that a parasitic wasp can learn to recognize a scent secreted by mated (or inseminated) females of the large cabbage white butterfly Pieris brassicae. This takes place while they hitch-hike with the cabbage white butterfly to a host plant where they parasitize the freshly laid butterfly eggs. A day later, the parasitic wasp is able to travel the same route. Parasitic wasps that did not have this ‘pleasant’ experience do not distinguish between mated cabbage butterflies and ‘uninteresting’ virgin ones. The researchers demonstrated in experiments that long-term memory is developed to remember the scent.
During mating, male large cabbage white butterflies transmit a special scent, benzyl cyanide, to their partners. This scent repels male rivals. The Minute (barely 0.5 mm long) parasitic wasps of the species Trichogramma brassicae take advantage of the anti-sex scent of the cabbage butterfly. They essentially engage in chemical espionage. Inexperienced parasitic wasps detect the anti-sex scent and use it to recognize mated female butterflies. The parasitic wasps hitch-hike with these mated butterflies. When the butterflies lay their eggs on a cabbage plant, the parasitic wasp climbs off the butterfly to lay its own eggs in the freshly laid butterfly eggs. In this way it parasitizes and kills the offspring of the butterfly.
For Trichogramma brassicae wasps this is an instinctive, innate behaviour. But this does not hold true for the closely related parasitic wasp Trichogramma evanescens. This wasp parasitizes the eggs of many species of moths and butterflies, including the large cabbage white butterfly. Inexperienced wasps of this species climb onto cabbage white butterflies just like Trichogramma brassicae, but show no preference for female butterflies that have mated. The researchers therefore concluded that they do not respond instinctively to benzyl cyanide.
A research team led by Dr Ties Huigens of the Laboratory of Entomology at Wageningen University wondered if the parasitic wasps could learn this behaviour. That appeared to be the case: Trichogramma evanescens do react to the anti-sex scent benzyl cyanide if they have previously had a positive experience with mated butterflies. After hitch-hiking once with such females and parasitizing freshly laid butterfly eggs, they thereafter climb specifically onto mated butterflies and hitch-hike with them. Either only hitch-hiking or only parasitizing the eggs were not sufficient by themselves. The researchers therefore concluded that the parasitic wasps learn to associate the anti-sex scent of the female butterflies with the reward of parasitizing the butterfly eggs.
The parasitic wasps continued to exhibit this learned behaviour even a day after the initial experience. This is an indication of long-term memory. In order to demonstrate this, researchers provided inhibitors for long-term memory. The parasitic wasps that ate these inhibitors (protein synthesis inhibitors) did not respond to the anti-sex scent a day after they had hitch-hiked with mated butterflies and parasitized freshly laid butterfly eggs. Apparently, the proteins needed for the development of long-term memory could not be produced. Obviously, these insects, with their extremely small ‘brains’ (estimated to be less than 10 nanolitres in volume) are able to develop a long-term memory, even though the formation of such memory requires a great deal of energy. Scientists know this, for example, because insects are less resistant to stress situations such as dessication after they have formed long-term memory.
The possession of long-term memory is very important for these short-lived parasitic wasps because they will probably only have a few opportunities to hitch-hike with mated female butterflies. If they were to immediately forget a positive experience, they could miss these few opportunities. The entomologists from Wageningen expect that learning the espionage-and-ride strategy is a widespread phenomenon because it is adaptive for many species of parasitic wasps killing insect eggs.
Jac Niessen | alfa
Further reports about: > Cabbage Butterfly interaction > Minute insect > Pieris brassicae > Trichogramma brassicae > anti-sex > benzyl cyanide > brassicae > butterfly > cabbage butterflies > hitch-hike > hitch-hiking > parasitic wasp > parasitize > protein synthesis inhibitors > specific butterfly anti-sex scent
Cancer diagnosis: no more needles?
25.05.2018 | Christian-Albrechts-Universität zu Kiel
Less is more? Gene switch for healthy aging found
25.05.2018 | Leibniz-Institut für Alternsforschung - Fritz-Lipmann-Institut e.V. (FLI)
The more electronics steer, accelerate and brake cars, the more important it is to protect them against cyber-attacks. That is why 15 partners from industry and academia will work together over the next three years on new approaches to IT security in self-driving cars. The joint project goes by the name Security For Connected, Autonomous Cars (SecForCARs) and has funding of €7.2 million from the German Federal Ministry of Education and Research. Infineon is leading the project.
Vehicles already offer diverse communication interfaces and more and more automated functions, such as distance and lane-keeping assist systems. At the same...
A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.
The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...
At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.
At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...
There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?
At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...
So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics
Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...
25.05.2018 | Event News
02.05.2018 | Event News
13.04.2018 | Event News
25.05.2018 | Event News
25.05.2018 | Machine Engineering
25.05.2018 | Life Sciences