Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

European dung-fly females all aflutter for large males

13.04.2012
European dung fly females prefer large males, making them the driving selective force behind the rare phenomenon in insects of large males and small females.
This is what evolutionary ecologists from the University of Zurich discovered when they compared North American and European dung flies, which not only differ in sexual size dimorphism (SSD), but also in their mating behavior.

European and North American black scavenger flies – also called dung flies as their larvae develop in the feces of vertebrates and thus break them down – belong to the same species. Nevertheless, they strongly differ in mating behavior and SSD. North American dung fly females are larger than males, the usual dimorphism in insects. European dung flies, however, are more unusual with males being considerably larger than females.

European and North American dung flies differ in their mating frequency. (picture: UZH)

In evolutionary biology, sexual selection for large males can be explained if they can reproduce more successfully than smaller ones, either because females prefer larger males or because the latter prevail more often in the competition for mates with other males. Evolutionary ecologists from the University of Zurich showed that female preference for large males is far greater in European fly populations than in their North American counterparts, which explains the different SSD.

Different mating behavior
North American dung fly males woo the females with a courtship dance. Project leader Wolf Blanckenhorn does not rule out the possibility that North American males also deploy pheromone-like scents during courtship. This courtship dance is entirely absent in the European flies: males mount the females relatively randomly, cling onto them with varying degrees of success and try to mate with them, even though they are often shaken off again by the females before copulation.
European dung flies copulate more often
European and North American dung flies also differ in their mating frequency. During their roughly 40-day adult life, European dung flies mate often, their North American counterparts only once or twice. “Frequent copulation requires more sperm from the males and therefore larger testes,” explains Blanckenhorn. This could well be a contributory factor in the European females’ greater preference for large males. However, the connection between the continental differences in SSD and mating behavior is still unclear: “What is an evolutionary cause and what an effect can only – if at all – be reconstructed indirectly today,” concludes Blanckenhorn.
Literature:
Nalini Puniamoorthy, Martin A. Schäfer and Wolf U. Blanckenhorn. Sexual Selection Account for the Geographic Reversal of Sexual Size Dimorphism in the Dung Fly Sepsis Punctum (Diptera: Sepsidae). Journal Evolution. March 16, 2012. doi:10.1111/j.1558-5646.2012.01599.x
Contact:
Prof. Dr. Wolf Blanckenhorn
Institute of Evolutionary Biology and Environmental Studies
University of Zurich
Tel.: +41 44 635 47 55
Email: wolf.blanckenhorn@ieu.uzh.ch

Nathalie Huber | Universität Zürich
Further information:
http://www.uzh.ch

More articles from Life Sciences:

nachricht Bare bones: Making bones transparent
27.04.2017 | California Institute of Technology

nachricht Link Discovered between Immune System, Brain Structure and Memory
26.04.2017 | Universität Basel

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

Bare bones: Making bones transparent

27.04.2017 | Life Sciences

Study offers new theoretical approach to describing non-equilibrium phase transitions

27.04.2017 | Physics and Astronomy

From volcano's slope, NASA instrument looks sky high and to the future

27.04.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>