11 April 2011

Wisdom of Crowds, Part 2

This process is known alternatively as emergence, spontaneous order, self-organization, or self-assembly. In biology, it is seen in the collective behavior witnessed in flocks of birds, schools of fish, insect colonies, and animal herds; in chemistry it is what causes snowflakes to form; at the molecular level it is what keeps that pencil from sinking into your hand and you from fusing with your chair. In political economics, F.A. Hayek referred to this process as cosmos or “grown order.” You and I might just call “freaky.”

And yet, this pattern of spontaneous, leaderless, sophisticated behavior is all around us. As Michael Shermer, Publisher of Skeptic Magazine, notes in his reply to the World Question:
“Almost everything important that happens in both nature and in society happens from the bottom up, not the top down. Water is a bottom up, self-organized emergent property of hydrogen and oxygen. Life is a bottom up, self-organized emergent property of organic molecules that coalesced into protein chains through nothing more than the input of energy into the system of Earth's early environment. The complex eukaryotic cells of which we are made are themselves the product of much simpler prokaryotic cells that merged together from the bottom up in a process of symbiosis that happens naturally when genomes are merged between two organisms. Evolution itself is a bottom up process of organisms just trying to make a living and get their genes into the next generation; out of that simple process emerges the diverse array of complex life we see today.”
Steven Johnson, author of Emergence: the connected lives of ants, brains, cities, and software, picks up on this theme, further describing emergent systems:
“They are bottom-up systems, not top-down. They get their smarts from below. In a more technical language, they are complex adaptive systems that display emergent behavior. In these systems agents residing on one scale start producing behavior that lies one scale above them: ants create colonies; urbanites create neighbourhoods; simple pattern-recognition software learns how to recommend new books. The movement from low-level rules to higher-level sophistication is what we call emergence.”
As Johnson notes, one popular area in which to observe emergent behaviors is in swarming insects: bees, ants, and fireflies. In so doing, Johnson echoes the words of the Psalmist, who exhorted: “Go to the ant, thou sluggard; consider her ways, and be wise: which having no guide, overseer, or ruler, provideth her meat in the summer, and gathereth her food in the harvest.”

In fact, some scientists have. Deborah Gordon, Professor at Stanford’s Department of Biology has built her career researching the behavior of ants. In one such study, Gordon investigated the sophisticated patterns created by blind army ants foraging for food or burying their dead. The upshot? Individually, the ants are not only blind, but also supremely unintelligent; collectively, however, they are brilliant, achieving not only advanced results that surpass their individual ability, but also border on geometric perfection.

This research has been borne out by Iain Couzin at Princeton’s Department of Ecology and Evolutionary Biology, who has looked at emergent behavior in not only ants, but also birds, fish, aphids, and none other than our very own Mormon cricket. Also of note is Cornell mathematician Steven Strogatz’ research on synchronicity in fireflies, which will blink in concert when gathered into swarms.

Man, A Social Animal
Lest we believe that spontaneous order is only found of insects and other ‘lower life-forms,’ there are abundant examples of human emergence. Without any scheming overlord, we human collectively organize into markets and cities. We assemble our collective knowledge in online encyclopedias. Even the language in which we communicate is the result of emergence.

One particularly cogent example of emergence in our species comes through our traffic patterns—both pedestrian and vehicular—in which we create formations not far off from that of Gordon’s ants. This spontaneous synchronicity was evidenced at the 2000 opening of London’s Millennium Bridge, the first structure spanning the Thames in five hundred years. Humans tend to walk in step with those around them (think birds and fish now), in order to keep pace and not bump into one another. When the Millennium Bridge first opened and the throngs began walking across it, this synchronicity caused the bridge to wobble from side to side, further forcing its pedestrians to walk in rhythm. This caused an even larger wobble, and eventually the bridge needed to be closed for stabilization.

On a more individual scale, the most recent neurological research indicates that humans’ cognitive function is itself a result of the spontaneous synthesis of multiple stimuli. For example, my nerves send numerous individual messages of color, smell, shape, and texture to my brain, which integrates them into one idea: orange juice. So perhaps Whitman wasn’t too far off when he wrote: “I am large. I contain multitudes.”

Who’s the Boss?
At the heart of this mountain of research into both animal and human behavior lies the “central mystery” described by Radiolab’s Jad Abumrad:
“What we’re studying here is the science of emergence which asks: ‘Where does organization come from? How do you get a neighborhood, a district, or a city? How do you get the complexity of an ant colony when there’s no leader and everyone in town is stupid?’”
In other words, can there be design without a designer?

It is my contention that behind every example of emergence, there is the presence of law. By this, I don’t mean the dictate of some despot, or even of a representative body, for this would only indicate top-down organization, and not spontaneous order at all. But whether it be the natural laws of physics or chemistry, societal norms, Adam Smith’s Invisible Hand, or Google algorithms, I believe that there is some principle—some set of rules—that guide all emergent behaviors.

A good illustration of how a set of simple rules can result in sophisticated patterns can be found in John Conway’s Game of Life (no, not the one with the plastic cars and peg people). Conway invented a computer program known as a “cellular automaton” in which a field of cells ‘live’ or ‘die’ by simple mathematical rules:
For a space that is 'populated':
§ Each cell with one or no neighbors dies, as if by loneliness.
§ Each cell with four or more neighbors dies, as if by overpopulation.
§ Each cell with two or three neighbors survives.
For a space that is 'empty' or 'unpopulated':
§ Each cell with three neighbors becomes populated.
Admittedly, The Game of Life is only an abstraction of what we observe in nature. The principle, however, holds true. Flocks of birds and schools of fish move as one body because each individual follows a set of simple rules: 1) fly in the same direction as your neighbors, 2) stay a specified distance away from your neighbors, and 3) avoid predators. And how about Gordon’s foraging ants? They too are obeying a genetic code directing them to follow the pheromone trails of other ants. And so on, through all examples of emergence.

This is not meant to denigrate the amazing nature of these behaviors—as if I were ruining a magic trick by revealing a trap door or hidden compartment—but rather to emphasize that if we are to take full advantage of the power of emergent systems, we must look to their underlying laws.


Kalen's Mommy said...

A+ I feel smarter for having read and understood that! Thank you for sharing it.

Russ said...

My professor apparently didn't agree with you. :)