Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Ant colonies: Behavioral variability wins

11.07.2011
Ant colonies with more behavioral variety are more successful / New findings in ant behavioral research

They attack other colonies, plunder and rob, kill other colonies' inhabitants or keep them as slaves: Ants are usually regarded as prototypes of social beings that are prepared to sacrifice their lives for their community, but they can also display extremely aggressive behavior towards other nests.

The evolution and behavior of ants, in particular the relationship between socially parasitic ants and their hosts, is the research topic of a work group headed by Professor Dr Susanne Foitzik at the Institute of Zoology at Johannes Gutenberg University Mainz (JGU). Evolutionary biologists at Mainz University found that ant colonies are more productive and raise more offspring when the workers in the colony display considerable variation in their levels of aggression. This variation in aggression is possibly part of their division of labor, which is regarded as the basis of the success of social insect societies.

There are more than 15,000 ant species worldwide. About a third of the 150 of the Central European species are parasitic, i.e., they live at the expense of other ant species. This includes "slave-making ants", which are being studied with particular interest at Johannes Gutenberg University Mainz. Temnothorax longispinosus is not one of these slave-making species but can become a victim itself: enslaved T. longispinosus worker ants search for food and care for the brood of the slavemaker. T. longispinosus lives in mixed oak forests in the northeastern United States of America (USA), where it builds nests in acorns, hickory nuts, and little twigs. They form colonies averaging 35 workers and feed mainly on dead insects. The workers are very small, measuring only between 2 and 3 millimeters in length.

"Temnothorax is particularly suitable for our experiments, as their colonies are easy to keep in the laboratory, and this makes it possible to use large sample sizes," explains Andreas Modlmeier, who is investigating the 'personality' of ants for his PhD thesis. The concept of 'personality’ has gained popularity among behavioral researchers in recent years. "We now assume that ants have a colony character, but that there are also many individual personality characteristics within an ant colony," explains Susanne Foitzik. One such characteristic is aggression. Aggressive colonies, for example, flee much more rarely than others do.

For the purpose of his experiments, Modlmeier brought individual ants together with a dead worker of another colony and observed how often aggressive interactions took place. He registered actions such as the opening of the mandibles (threat display), biting, pulling, and stinging. Ten worker ants were selected from each of 39 different colonies to be classified by their size, level of aggression, and exploratory behavior. It was shown that the productivity of ant colonies - measured by the total biomass in new workers and sexuals produced per worker ant - increased with the variation in the level of aggression within the colony; in other words, this correlated with the differences displayed in level of aggression within each set of ten ant workers. "Colonies might be more productive when tasks such as nest defense and brood care are distributed between specialized workers with different aggression levels," is Modlmeier's assumption. Animals with high aggression levels could participate in competition and fights with other colonies, while less aggressive social workers care for the offspring. A remarkable finding was that not one of the 39 colonies was highly aggressive. "There are no fully aggressive colonies. It seems that this is not beneficial in the natural world and could rather be a disadvantage," assumes Modlmeier.

It had previously been suggested that there is a connection between the character or behavior of worker ants and the division of labor in a colony, and that this might possibly be the basis for the ecological success of social insects, but this hypothesis had not been proven yet. Modlmeier has now provided the first empirical proof that variability in behavior patterns, which might be the basis of the division of labor in ant colonies, enhances the productivity and thus the fitness of social insect colonies.

The research on the behavior and personality characteristics of ants has been funded as part of the project "The evolutionary significance of within- and between-colony variation in behavior, morphology, genetic composition and immuno-competence in ants," funded by the German Research Foundation (DFG) since November 2010.

Publication:
Andreas P. Modlmeier, Susanne Foitzik: Productivity increases with variation in aggression among group members in Temnothorax ants, Behavioral Ecology, 28 June 2011.

doi:10.1093/beheco/arr086

Petra Giegerich | idw
Further information:
http://www.uni-mainz.de/eng/14380.php
http://www.bio.uni-mainz.de/zoo/evobio/index_ENG.php

Further reports about: ANT Temnothorax ant colonies level of aggression

More articles from Life Sciences:

nachricht Cancer diagnosis: no more needles?
25.05.2018 | Christian-Albrechts-Universität zu Kiel

nachricht Less is more? Gene switch for healthy aging found
25.05.2018 | Leibniz-Institut für Alternsforschung - Fritz-Lipmann-Institut e.V. (FLI)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Powerful IT security for the car of the future – research alliance develops new approaches

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...

Im Focus: Molecular switch will facilitate the development of pioneering electro-optical devices

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...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

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...

Im Focus: Self-illuminating pixels for a new display generation

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...

Im Focus: Explanation for puzzling quantum oscillations has been found

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...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

In focus: Climate adapted plants

25.05.2018 | Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

 
Latest News

In focus: Climate adapted plants

25.05.2018 | Event News

Flow probes from the 3D printer

25.05.2018 | Machine Engineering

Less is more? Gene switch for healthy aging found

25.05.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>