Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


From Chaos to Order: How Ants optimize Food Search


Ants are capable of complex problem-solving strategies that could be widely applied as optimization techniques.

An individual ant searching for food walks in random ways, biologists found. Yet the collective foraging behaviour of ants goes well beyond that, as a mathematical study to be published in the Proceedings of the National Academy of Sciences reveals: The animal movements at a certain point change from chaos to order. This happens in a surprisingly efficient self-organized way. Understanding the ants could help analyze similar phenomena - for instance how humans roam in the internet.

“Ants have a nest so they need something like a strategy to bring home the food they find,” says lead-author Lixiang Li who is affiliated both to the Information Security Center, State Key Laboratory of Networking and Switching Technology, at the Beijing University of Posts and Communications, and to the Potsdam Institute for Climate Impact Research. “We argue that this is a factor, largely underestimated so far, that actually determines their behavior.”

Leaving a trail of scent

The Chinese-German research team basically put almost everything that is known about the foraging of ants into equations and algorithms and fed this into their computers. They assume that there are three stages of the complex feed-search movements of an ant colony: Initially, scout ants indeed circle around in a seemingly chaotic way. When exhausted, they go back to the nest to eat and rest. However, when one of them finds some food in the vicinity of the colony, it takes a tiny piece of it to the nest, leaving a trail of a scent-emanating substance called pheromones.

Other ants will follow that trail to find the food and bring some of it home. Their orchestration is still weak because there is so little pheromone on the trail. Due to their large number, the ants go lots of different ways to the food source and back to the nest, leaving again trails of scent. This eventually leads to an optimization of the path: Since pheromones are evaporative, the scent is the stronger the shorter the trail is – so more ants follow the shortest trail, again leaving scent marks. This generates a self-reinforcing effect of efficiency – the ants waste a lot less time and energy than they would in continued chaotic foraging.

Importantly, the researchers found that the experience of individual ants contributes to their foraging success – something also neglected in previous research. Older ants have a better knowledge of the nests surroundings. The foraging of younger ants is a learning process rather than an effective contribution to scout food, according to the study.

 “A highly efficient complex network”

“While the single ant is certainly not smart, the collective acts in a way that I’m tempted to call intelligent,” says co-author Jürgen Kurths who leads PIK’s research domain Transdisciplinary Concepts and Methods. “The principle of self-organisation is known from for instance fish swarms, but it is the homing which makes the ants so interesting.” While the study of foraging behavior of ants is certainly of practical ecological importance, the study’s authors are mainly interested in understanding the fundamental patterns of nonlinear phenomena. “The ants collectively form a highly efficient complex network,” Kurths explains. “And this is something we find in many natural and social systems.”

So the mathematical model developed in studying the ants is applicable not only to very different kinds of animals which share just the feature that they have a home to return to, such as Albatrosses. It also provides a new perspective on behavioral patterns of humans in areas as diverse as the evolution of web services and smart transportation systems.

Article: Li, L., Peng, H., Kurths, J., Yang, Y., Schellnhuber, H.J. (2014): Chaos-order transition in foraging behavior of ants. Proceedings of the National Academy of Sciences, Early Edition [DOI:10.1073/pnas.1407083111]

Weblink to PNAS where the article will publish any day in the week after 26 May:

For further information please contact:
PIK press office
Phone: +49 331 288 25 07
Twitter: @PIK_Climate

Jonas Viering | PIK Potsdam
Further information:

Further reports about: Academy Food Search ants behavior chaotic colony found individual mathematical movements phenomena pheromones

More articles from Life Sciences:

nachricht Two decades of training students and experts in tracking infectious disease
27.11.2015 | Hochschule für Angewandte Wissenschaften Hamburg

nachricht Increased carbon dioxide enhances plankton growth, opposite of what was expected
27.11.2015 | Bigelow Laboratory for Ocean Sciences

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Climate study finds evidence of global shift in the 1980s

Planet Earth experienced a global climate shift in the late 1980s on an unprecedented scale, fuelled by anthropogenic warming and a volcanic eruption, according to new research published this week.

Scientists say that a major step change, or ‘regime shift’, in the Earth’s biophysical systems, from the upper atmosphere to the depths of the ocean and from...

Im Focus: Innovative Photovoltaics – from the Lab to the Façade

Fraunhofer ISE Demonstrates New Cell and Module Technologies on its Outer Building Façade

The Fraunhofer Institute for Solar Energy Systems ISE has installed 70 photovoltaic modules on the outer façade of one of its lab buildings. The modules were...

Im Focus: Lactate for Brain Energy

Nerve cells cover their high energy demand with glucose and lactate. Scientists of the University of Zurich now provide new support for this. They show for the first time in the intact mouse brain evidence for an exchange of lactate between different brain cells. With this study they were able to confirm a 20-year old hypothesis.

In comparison to other organs, the human brain has the highest energy requirements. The supply of energy for nerve cells and the particular role of lactic acid...

Im Focus: Laser process simulation available as app for first time

In laser material processing, the simulation of processes has made great strides over the past few years. Today, the software can predict relatively well what will happen on the workpiece. Unfortunately, it is also highly complex and requires a lot of computing time. Thanks to clever simplification, experts from Fraunhofer ILT are now able to offer the first-ever simulation software that calculates processes in real time and also runs on tablet computers and smartphones. The fast software enables users to do without expensive experiments and to find optimum process parameters even more effectively.

Before now, the reliable simulation of laser processes was a job for experts. Armed with sophisticated software packages and after many hours on computer...

Im Focus: Quantum Simulation: A Better Understanding of Magnetism

Heidelberg physicists use ultracold atoms to imitate the behaviour of electrons in a solid

Researchers at Heidelberg University have devised a new way to study the phenomenon of magnetism. Using ultracold atoms at near absolute zero, they prepared a...

All Focus news of the innovation-report >>>



Event News

Fraunhofer’s Urban Futures Conference: 2 days in the city of the future

25.11.2015 | Event News

Gluten oder nicht Gluten? Überempfindlichkeit auf Weizen kann unterschiedliche Ursachen haben

17.11.2015 | Event News

Art Collection Deutsche Börse zeigt Ausstellung „Traces of Disorder“

21.10.2015 | Event News

Latest News

Siemens to supply 126 megawatts to onshore wind power plants in Scotland

27.11.2015 | Press release

Two decades of training students and experts in tracking infectious disease

27.11.2015 | Life Sciences

Coming to a monitor near you: A defect-free, molecule-thick film

27.11.2015 | Materials Sciences

More VideoLinks >>>