• Question from:Adam

Hello, I recently read an article about various insects that use swarm mentality to solve problems that individually, they could not, the article was in the latest National Geographic and Immediately caught my eye. now I'm not in the UK nor am I going to heckle you about evolution or anything (I suppose you get quite a bit of that), but I am very interested in this topic, specifically in the way in witch the insects involved think in order to solve these problems, the article mentioned ants that essentially change the job they do for the day based upon weather conditions, the displacement of food, digging, and other various jobs. Some of these were explained in the article, such as how many foraging ants are sent to a specific place (by way of pheromone signals i believe), but others such as wind, temperature, the threat of predators were not explained, so my first question would have to be the ways in witch ant colonies work around these obstacles and distribute jobs in the fashion.
My second question is far more broad and may be difficult to answer as indeed I'm not completely sure of the question. I am interested in the ways in witch swarms work in different facets of biology, bees, locusts, termites, ants, but also flocks of birds and herds of cattle and such. My question comes in the form of the best explanation you can give me for these phenomenon, I would like to know how this happens in different populations, how they likely came to evolve in this way, but most specifically, the rules that govern each "swarm."
I realize this is a lot for one e-mail, and may be a bit much to handle, I will understand if some of the information is simply not known in the scientific community at the time, and I'm no creationist, so no worries on that front.
I am a philosophy major at Manhattan college in the US, and I'm very interested in the dynamics of the group versus the individual, it would be especially interesting to know how this manifests itself in the natural world.
Thank you, you are doing a great service to the UK and thankfully to others as well
I hope you don't get overburdened with evolution debates, I know from personal experience that they can be emotionally wearing

-Adam

Dear Adam -- This is very much a hot topic, not just in the study of social behaviour, but also developmental biology, artificial intelligence and computer design, as well as city planners trying to control traffic flow and large crowds of people. Whether it's 10 million leaf-cutter ants building a nest with air-conditioning, fungus 'gardens' and efficient waste-disposal, or cells migrating to the right place and differentiating to produce an organ in the body, or massive database search-engines like Google, the question is the same: how do design (by engineering or natural selection, as appropriate) individually 'stupid' units, following simple rules, that when combined together produce complex, adaptive behaviour.

In the case of ants, flocking starlings, shoaling fish and cells forming tissues and organs, there is potentially both local information (what the 'units' next to you are doing) and long-distance information (e.g. pheromone trails laid by other ants or a diffusing chemical from another tissue further away), but in all cases there is no central 'controller' or intelligence that has The Plan and is pulling the strings. In fact, remarkably complex and adaptive social behaviour can be produced by every individual following very simple rules.

I can do no better than refer you to the web pages of one of the top people in this field, Iain Couzin, who splits his time between Oxford and Princeton universities. http://www.princeton.edu/~icouzin/    There you will find both popular and technical papers on phenomena he has studied (and mathematically modelled) such as army ants forming organised 'traffic lanes' to and from food sources, fish schools avoiding predators, locust swarms marching, and the behaviour human crowds.

Very often some simple rules such as 'go in the same direction as those close to me' and 'don't get too near or bump into others near me' are sufficient to produce what looks like a highly organised group movement.  Actually, when you think about it, it's going to principles like this that wil help understand how the human mind works, because no individual neurone or group of neurones 'knows' what it's trying to do, and there is no controlling 'me' in the middle orchestrating it all (what philosophers would call the fallacy of mind-brain duality), and yet the whole collection ofneurones clearly does act in a coordinated adaptive way and produces a strong a strong sense of 'self' and self-control. Deep stuff!