Featured Research

from universities, journals, and other organizations

European dung-fly females all aflutter for large males

Date:
April 13, 2012
Source:
University of Zurich
Summary:
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 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 dung flies differ in their mating frequency.
Credit: UZH

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.

Related Articles


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. 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.


Story Source:

The above story is based on materials provided by University of Zurich. Note: Materials may be edited for content and length.


Journal Reference:

  1. Nalini Puniamoorthy, Martin A. Schδfer, Wolf U. Blanckenhorn. Sexual Selection Accounts for the Geographic Reversal of Sexual Size Dimorphism in the Dung Fly, Sepsis Punctum (Diptera: Sepsidae). Evolution, 2012; DOI: 10.1111/j.1558-5646.2012.01599.x

Cite This Page:

University of Zurich. "European dung-fly females all aflutter for large males." ScienceDaily. ScienceDaily, 13 April 2012. <www.sciencedaily.com/releases/2012/04/120413101112.htm>.
University of Zurich. (2012, April 13). European dung-fly females all aflutter for large males. ScienceDaily. Retrieved October 24, 2014 from www.sciencedaily.com/releases/2012/04/120413101112.htm
University of Zurich. "European dung-fly females all aflutter for large males." ScienceDaily. www.sciencedaily.com/releases/2012/04/120413101112.htm (accessed October 24, 2014).

Share This



More Plants & Animals News

Friday, October 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Reuters - Innovations Video Online (Oct. 24, 2014) — Miniature deep sea animals discovered off the Australian coast almost three decades ago are puzzling scientists, who say the organisms have proved impossible to categorise. Academics at the Natural History of Denmark have appealed to the world scientific community for help, saying that further information on Dendrogramma enigmatica and Dendrogramma discoides could answer key evolutionary questions. Jim Drury has more. Video provided by Reuters
Powered by NewsLook.com
Black Bear Cub Goes Sunday Shopping

Black Bear Cub Goes Sunday Shopping

Reuters - Light News Video Online (Oct. 23, 2014) — Price check on honey? Bear cub startles Oregon drugstore shoppers. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Dances With Wolves in China's Wild West

Dances With Wolves in China's Wild West

AFP (Oct. 23, 2014) — One man is on a mission to boost the population of wolves in China's violence-wracked far west. The animal - symbol of the Uighur minority there - is under threat with a massive human resettlement program in the region. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com
Breakfast Debate: To Eat Or Not To Eat?

Breakfast Debate: To Eat Or Not To Eat?

Newsy (Oct. 23, 2014) — Conflicting studies published in the same week re-ignited the debate over whether we should be eating breakfast. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins