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: www.pnas.org/cgi/doi/10.1073/pnas.1407083111
For further information please contact:
PIK press office
Phone: +49 331 288 25 07
Jonas Viering | PIK Potsdam
Cryo-electron microscopy achieves unprecedented resolution using new computational methods
24.03.2017 | DOE/Lawrence Berkeley National Laboratory
How cheetahs stay fit and healthy
24.03.2017 | Forschungsverbund Berlin e.V.
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
24.03.2017 | Materials Sciences
24.03.2017 | Physics and Astronomy
24.03.2017 | Physics and Astronomy