Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Division of labor among social insects: All-rounders better cope with threats than specialists

08.03.2016

Ant colonies that are highly specialized have lower chances of survival when sudden changes occur

A characteristic of insect societies such as ants is the way tasks are distributed among group members. Not only queens and worker ants have clearly defined responsibilities but the workers themselves also have particular jobs to do when, for example, it comes to the care of the young, defense, and nest building activities. It is widely assumed that this division of labor is an essential factor that determines the success of such social groups. According to this view, a high degree of specialization provides advantages because the individual tasks are performed better and more effectively. It seems, however, that this advantage may actually be a great disadvantage in special circumstances. As researchers at Johannes Gutenberg University Mainz (JGU) have discovered, highly specialized ants lack the flexibility to adapt to new situations—with serious consequences for the entire colony.


Part of a colony of Temnothorax longispinosus with two queens, workers, and offspring in various stages of development

photo/©: Susanne Foitzik

"Our findings provide an explanation of why all-rounders tend to be ubiquitous and show how important they are for the flexibility and robustness of entire societies," said evolutionary biologist Professor Susanne Foitzik, commenting on the latest findings of her research group at Mainz University. Foitzik and Evelien Jongepier investigated what happens when ant colonies with different degrees of specialization are exposed to an external threat. They tested around 3,800 ants of the species Temnothorax longispinosus and, based on their behavior, formed separate ant colonies consisting of either all-rounders or specialists. These colonies were then subjected to attacks by the slave-making ants Temnothorax americanus and as a consequence were forced to either flee or defend themselves. The social parasite T. americanus carries out raids on neighboring host colonies in order to steal their young, often killing adult worker ants and the queen in the process.

"In contrast with the widely held assumption that an individual specialization provides social advantages, we have found that specialization can in fact have a negative impact on the propagation and the chances of survival and growth of a colony," summarized Jongepier, first author of the study. Ant colonies which were specialized in defense and the care of offspring lost almost 80 percent of their brood when attacked by slave-maker ants. All-rounders, in contrast, were able to save over half of their offspring. For a species such as T. longispinosus, which only reproduces once a year, such heavy brood losses can mean the virtual destruction of the colony or at least represent a serious threat to its future chances of survival. Such fitness costs associated with strict specialization mean that the all-rounder strategy probably has the better prospects of success in a natural environment with slave-makers. Ant communities living near to slave-makers are less highly specialized than colonies in areas which are free of these social parasites. "In the field, slave-makers represent an evolutionary factor that counteracts the development of higher levels of specialization," clarified Foitzik.

Flexibility in behavior pays off

Discussing their findings, Foitzik and Jongepier postulate that specialized communities probably have difficulty in changing their activities and so they are less flexible. Even if the findings cannot be applied directly to other spheres, they nevertheless provide insights into the evolution of social groups and provide indications of their potential viability. "Our results show how important it is to take ecological aspects into account when organizing work and individual patterns of behavior if benefits for the whole society are to be obtained," the researchers concluded. Thus, flexibility in behavior would be advantageous not only for ant colonies but also in connection with quite different organizational structures as well, especially when frequent disruptions are possible. These could range from metabolic cycles with all-rounder enzymes to financial systems that do not rely on just a few specialized institutions and are thus more stable.

Images:
http://www.uni-mainz.de/bilder_presse/10_zoologie_ameisen_generalisten_01.jpg
Part of a colony of Temnothorax longispinosus with two queens, workers, and offspring in various stages of development
photo/©: Susanne Foitzik

http://www.uni-mainz.de/bilder_presse/10_zoologie_ameisen_generalisten_02.jpg
Workers of the host species Temnothorax longispinosus fighting a slightly larger worker of the T. americanus slave-maker species that has invaded their colony
photo/©: Susanne Foitzik

http://www.uni-mainz.de/bilder_presse/10_zoologie_ameisen_generalisten_03.jpg
A T. americanus slave-maker worker ant (left) interacting with a slave worker of the species T. longispinosus (right)
photo/©: Susanne Foitzik

Publication:
Evelien Jongepier, Susanne Foitzik
Fitness costs of worker specialization for ant societies
Proceedings of the Royal Society B, 13 January 2016
DOI: 10.1098/rspb.2015.2572

Further information:
Professor Dr. Susanne Foitzik
Institute of Zoology – Evolutionary Biology
Johannes Gutenberg University Mainz (JGU)
55099 Mainz, GERMANY
phone +49 6131 39-27840
fax +49 6131 39-27850
E-mail: foitzik@uni-mainz.de
http://www.bio.uni-mainz.de/zoo/evobio/index_ENG.php

Weitere Informationen:

http://rspb.royalsocietypublishing.org/content/283/1822/20152572 (Article) ;
http://www.uni-mainz.de/presse/19919_ENG_HTML.php — press release "Parasitic tapeworm influences the behavior and lifespan of uninfected members of ant colonies", 1 Dec. 2015

Petra Giegerich | idw - Informationsdienst Wissenschaft

More articles from Life Sciences:

nachricht Making fuel out of thick air
08.12.2017 | DOE/Argonne National Laboratory

nachricht ‘Spying’ on the hidden geometry of complex networks through machine intelligence
08.12.2017 | Technische Universität Dresden

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

Im Focus: Virtual Reality for Bacteria

An interdisciplinary group of researchers interfaced individual bacteria with a computer to build a hybrid bio-digital circuit - Study published in Nature Communications

Scientists at the Institute of Science and Technology Austria (IST Austria) have managed to control the behavior of individual bacteria by connecting them to a...

Im Focus: A space-time sensor for light-matter interactions

Physicists in the Laboratory for Attosecond Physics (run jointly by LMU Munich and the Max Planck Institute for Quantum Optics) have developed an attosecond electron microscope that allows them to visualize the dispersion of light in time and space, and observe the motions of electrons in atoms.

The most basic of all physical interactions in nature is that between light and matter. This interaction takes place in attosecond times (i.e. billionths of a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

PhoxTroT: Optical Interconnect Technologies Revolutionized Data Centers and HPC Systems

11.12.2017 | Information Technology

Large-scale battery storage system in field trial

11.12.2017 | Power and Electrical Engineering

See, understand and experience the work of the future

11.12.2017 | Event News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>