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 Nanoparticle Exposure Can Awaken Dormant Viruses in the Lungs
16.01.2017 | Helmholtz Zentrum München - Deutsches Forschungszentrum für Gesundheit und Umwelt

nachricht Cholera bacteria infect more effectively with a simple twist of shape
13.01.2017 | Princeton University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

Im Focus: Bacterial Pac Man molecule snaps at sugar

Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.

The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

Water - as the underlying driver of the Earth’s carbon cycle

17.01.2017 | Earth Sciences

Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

17.01.2017 | Materials Sciences

Smart homes will “LISTEN” to your voice

17.01.2017 | Architecture and Construction

VideoLinks
B2B-VideoLinks
More VideoLinks >>>