When selecting a resource to exploit, an insect colony must take into account at least two constraints: the resource must be abundant enough to sustain the whole group, but not too large to limit exploitation costs, and risks of conflicts with other colonies. Following recent results on cockroaches and ants, we introduce here a behavioral mechanism that satisfies these two constraints. Individuals simply modulate their probability to switch to another resource as a function of the local density of conspecifics locally detected. As a result, the individuals gather at the smallest resource that can host the whole group, hence reducing competition and exploitation costs while fulfilling the overall group's needs. Our analysis reveals that the group becomes better at discriminating between similar resources as it grows in size. Also, the discrimination mechanism is flexible and the group readily switches to a better suited resource as it appears in the environment. The collective decision emerges through the self-organization of individuals, that is, in absence of any centralized control. It also requires a minimal individual cognitive investment, making the proposed mechanism likely to occur in other social species and suitable for the development of distributed decision making tools.

The article can be found here: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0019888

Stigmergy – the phenomenon of indirect communication mediated by modifications of the environment – was first conceptualized by zoologist Pierre-Paul Grasse in his ground-breaking work on termite colonies (Grasse 1959). It wasn’t until 1999 that Grasse’s work was brought to a wider audience by Eric Bonabeau et al (1999) in a special issue of Artificial Life. Since then interest in stigmergic systems has blossomed with researchers recognizing the application of Grasse’s insights to stock markets, economies, traffic patterns, supply logistics, computer networks, resource allocation, urban sprawl, and cultural memes. New forms of stigmergy have been exponentially expanded through the affordances of digital technology: Google’s recommendation algorithm, Amazon’s filtering algorithm, wiki, open source software, weblogs, and a whole range of “social media” are now deemed as essentially stigmergic.

Though the concept of stigmergy has typically been associated with ant- or swarm-like “agents” with minimal cognitive ability or with creatures of a somewhat higher cognitive capacity such as fish (schooling patterns) or birds (flocking patterns) or sheep (herding behavior), stigmergy offers a powerful tool to be deployed in the human domain. The editors of this special issue are thus looking for contributions that have human-human (social, organizational, and socio-technical) stigmergy as the main focus.

Proposals are invited from social scientists, social epistemologists, cognitive scientists, economists, group decision theorists, collective intentionality theorists, computational sociologists, network theorists, multi-agent modelers, and indeed researchers from any discipline that has social complexity and coordination as a core topic.

Papers that are theoretical, experimental, or computational in orientation are welcome. Please send proposals of no more than 300 words to lesliemarsh [at] gmail [dot] com with “Stigmergy/Cognitive Systems Research” in the subject line. The deadline for proposals is Nov 1, 2010.

All papers will be subject to double blind review by a least two referees and accepted papers will be published in a special issue of Cognitive Systems Research

Secret of Annoying Crowds Revealed – From Science Now

Push, shout, or politely excuse yourself all you want, but those slowpokes in your way just won't budge. A new study shows a long-neglected reason why: Up to 70% of people in crowds socially glue themselves into groups of two or more, slowing down traffic. What's worse, as crowds gets denser, groups bend into anti-aerodynamic shapes that exacerbate the problem. The study may be a boon to urban planners.

The Walking Behaviour of Pedestrian Social Groups and Its Impact on Crowd Dynamics – From PLoS ONE

Human crowd motion is mainly driven by self-organized processes based on local interactions among pedestrians. While most studies of crowd behaviour consider only interactions among isolated individuals, it turns out that up to 70% of people in a crowd are actually moving in groups, such as friends, couples, or families walking together. These groups constitute medium-scale aggregated structures and their impact on crowd dynamics is still largely unknown. In this work, we analyze the motion of approximately 1500 pedestrian groups under natural condition, and show that social interactions among group members generate typical group walking patterns that influence crowd dynamics. At low density, group members tend to walk side by side, forming a line perpendicular to the walking direction. As the density increases, however, the linear walking formation is bent forward, turning it into a V-like pattern. These spatial patterns can be well described by a model based on social communication between group members. We show that the V-like walking pattern facilitates social interactions within the group, but reduces the flow because of its “non-aerodynamic” shape. Therefore, when crowd density increases, the group organization results from a trade-off between walking faster and facilitating social exchange. These insights demonstrate that crowd dynamics is not only determined by physical constraints induced by other pedestrians and the environment, but also significantly by communicative, social interactions among individuals.

For those interested by this topic (as I am), here is the address of the NY Times article: http://www.nytimes.com/2010/03/02/science/02evo.html. For more information, hereafter are some links towards some of the leaders of this movement that tends to bring together cultural and natural evolution:

• Professor Kevin Laland, University of St Andrews, Scotland.
• Professor Robert Boyd, University of California, Los Angeles.
• Professor Peter Richerson, University of California, Davis.
• Professor Mark Stoneking, Max Planck Institute for Evolutionary Anthropology, Germany.

In the heart of Africa's savannah lies a city that is a model of sustainable development. Its buttressed towers are built entirely from natural, biodegradable materials. Its inhabitants live and work in quarters that are air-conditioned and humidity-regulated, without consuming a single watt of electricity. Water comes from wells that dip deep into the earth, and food is cultivated self-sufficiently in gardens within its walls. This metropolis is not just eco-friendly: with its curved walls and graceful arches, it is rather beautiful too.

This is no human city, of course. It is a termite mound.

To read the rest of this article, click here: For sustainable architecture, think bug – life – 22 February 2010 – New Scientist.

Swarm Cognition is the juxtaposition of two relatively unrelated concepts that evoke, on the one hand, the power of collective behaviours displayed by natural swarms, and on the other hand the complexity of cognitive processes in the vertebrate brain. In recent years, scientists from various disciplines have been suggesting that, at a certain level of description, operational principles used to account for the behaviour of natural swarms may turn out to be extremely powerful tools to identify the neuroscientic basis of cognition. Generally speaking, these studies claim that the massively parallel animal-to-animal interactions which operationally explain cognitive processes of natural swarms are functionally similar to neuron-to-neuron communication which underlie the cognitive abilities of living organisms, including humans. With this premise, research work in Swarm Cognition aims at identifying the operational principles of cognitive behaviour by calling upon the underlying mechanisms of self-organising systems, i.e., systems whose internal organisation changes without being guided by an outside source.

We encourage submissions of innovative research work which highlights the importance of the mechanisms of self-organisation as operational principles to explain cognitive processes displayed by individuals or collectives, both natural and artificial. Particularly welcome are contributions focusing on the distributed mechanisms underlying cognitive processes, like, for instance, decision-making, attention, learning or memory.
Topics of interest in relationship to the above issues include but are not limited to:

• Cognitive and computational neurosciences
• Cognitive and social ethology
• Swarm intelligence and swarm robotics
• Adaptive control
• Systems biology
• Neural computation and distributed representations
• Cultural evolution and Learning
• Cognitive sociology
• Bounded rationality

Important dates for this special issue are: 

• Manuscript due: March 15, 2010
• Notication: May 31, 2010
• Final manuscript due: July 19, 2010

The first part of this current issue is now online and contains the following articles:

1. Collective Behavior (p 412-438), Robert L. Goldstone, Todd M. Gureckis, DOI: 10.1111/j.1756-8765.2009.01038.x
2. Web-Based Experiments for the Study of Collective Social Dynamics in Cultural Markets (p 439-468), Matthew J. Salganik, Duncan J. Watts, DOI: 10.1111/j.1756-8765.2009.01030.x
3. Collective Information Processing and Pattern Formation in Swarms, Flocks, and Crowds (p 469-497), Mehdi Moussaid, Simon Garnier, Guy Theraulaz, Dirk Helbing, DOI: 10.1111/j.1756-8765.2009.01028.x
4. Social Optimization in the Presence of Cognitive Local Optima: Effects of Social Network Topology and Interaction Mode (p 498-522), James Kennedy, DOI: 10.1111/j.1756-8765.2009.01035.x
5. Modeling the Emergence of Language as an Embodied Collective Cognitive Activity (p 523-546), Edwin Hutchins, Christine M. Johnson, DOI: 10.1111/j.1756-8765.2009.01033.x