Back in 2004 I spent my Christmas break at a seaside town in Cornwall. The damp British winter had kept the beaches rather quiet, which was fine by me. The scenery was stunning, even if I wasn’t tempted to go for a dip in the surf. One memory that sticks out is sitting by the cliffs with my girlfriend, watching a flock of small birds ride the air currents against the sunset.
I’m fascinated by swarms of anything. Researchers from Hungary have recently applied models that describe the behaviour of particles to understand how flocks of birds move as a single unit. The collective power of honey bees aggressively defending their nest against a Japanese hornet using nothing more than their body heat still leaves me amazed. Ants marching to their eventual demise in a spiral of death, commanded by a simple rule of ‘follow the leader’ serve to show what happens when nature suffers a glitch.
Yet when I stop to think about it, my fascination with collective behaviour is based on an a rather arbitrary delineation based on individual units. I don’t think of my genes as individuals, nor my cells. Yet I’m more or less a colony of membrane-enclosed entities that can be thought of as cooperating components. My brain draws a line around the outside of my skin, so I think of all similar lines as boundaries.
A single bacterium is an individual, while a colony isn’t. Once it has a specific role – once a cell differentiates with respect to the others – the collective is suddenly an individual again. However a bee with physiological and behavioural differentiation within a hive doesn’t make us view the hive as an individual. It’s still a single bee.
It might seem rather pedantic to give this much thought, but when it comes to understanding behaviour – especially that of humans – I feel the innate biases we hold about the concept of the individual can lead us astray. We’re so hung up on concepts of free will and theory of mind that the idea of being influenced by the collective to any significant extent feels somehow heretical. It’s easy to see hive-mind behaviour in others, of course…but never ourselves.
That’s not to say we’re at the complete mercy of our social group. But how we behave as individuals can’t be easily removed from the context of a collective either.
The true beauty of swarms, hives and flocks is that relatively simple rules can create the illusion of something complex, like a Mandelbrot set giving rise to a piece of fractal artwork. Of course, as a line of ants following the circular pheromone trail to starvation discover, all rules have their limits. Finding ours is a glorious challenge that is necessary not just for us as individuals, but for us as a species.