Stephen Baxter - Coalescent

I smiled. “ Important. This from a man who thinks that alien ships are making three-point turns in the core of the Earth. What could be important compared to that?”

“More than you know,” he said. “George, what causes traffic jams?”

I shrugged. “Well, you need a crowded road. Roadworks. Breakdowns.”

“What roadworks?”

There were no works ahead, no obvious breakdowns or crash sites. And yet we were stationary.

Peter said, “George, to make a traffic jam all you need is traffic. The jams just occur. Look around. All that makes up the traffic is individual drivers — right? And each of us makes individual decisions, based, minute to minute, on what our neighbors are doing. There’s not a one of us who intends to cause a jam, that’s for sure. And there’s not one of us who has a global view of the traffic, like you’d get from a police chopper, say. There are only the drivers.

“And yet, from our individual decisions made in ignorance, the traffic jam emerges, a giant organized structure involving maybe thousands of cars. So where does the jam come from?”

We were moving forward by now, in fits and starts, but, scarily, he took his eyes off the road to look at me, testing my understanding.

“I don’t know,” I admitted.

“This is what they call emergence , George,” he said. “From simple rules, applied at a low level, like the decisions made by the drivers on this damn road — and with feedback to amplify the effects, like a slowing car forcing a slowdown behind it — large-scale structures can emerge. It’s called self-organized criticality. The traffic always tries to organize itself to get as many cars through as possible, but it’s constantly on the point of breakdown. The jams are like waves, or ripples, passing back and forth along the lines of cars.”

It was hard for me to concentrate on this. Too much had happened today. Sitting in that lurching car, I felt as if I were in a dream. I groped for the point he was trying to make. “So the Order is like a traffic jam,” I said. “The Order is a kind of feedback effect.”

“We’ll get to the Order. One step at a time.” He wrenched the wheel, and we plunged out of the traffic toward a junction that would lead us back toward the center of the city.

We roared up Mussolini’s great avenue, hared through the Venezia, lurched left onto the Plebiscito. Peter rammed the long-suffering Punto into a few feet of parking space. I wouldn’t have believed it if I hadn’t seen it.

We got out of the car, locked it up, and made for a bar. I wanted coffee. Peter went to order while I found a table.

Peter returned with a bottle of beer. “You need this more than coffee, believe me.”

And oddly, he was right. Something about the heft of the bottle in my hand, the cool tang of the beer, that first subtle softening of perception as the alcohol kicked in, brought me back to reality, or anyhow my version of it. I raised the bottle to Peter. “Here’s to me,” I said. “And what I truly am. An appendage clamped to the mouth of a beer bottle.”

He had a Coke Light; he raised it ironically. “As a destiny, that will do,” he said seriously. “Just don’t lose yourself down in that hole in the ground …”

“Emergence,” I said. “Traffic jams.”

“Yes. And think about cities.”

“Cities?”

“Sure. Who plans cities? Oh, I know we try to now, but in the past — say, in Rome — it wasn’t even attempted. But cities have patterns nevertheless, stable patterns that persist far beyond any human time horizon: neighborhoods that are devoted to fashion, or upscale shops, or artists; poor, crime-ridden districts, upmarket rich areas. Bright lights attract more bright lights, and clusters start.

“This is what emergence is: agents working at one scale unconsciously producing patterns at one level above them. Drivers rushing to work create traffic jams; urbanites keeping up with the Joneses create neighborhoods.”

“Unconsciously. They create these patterns without meaning to.”

“ Yes. That’s the point. Local decision making, coupled with feedback, does it for them. We humans think we’re in control. In fact we’re enmeshed in emergent structures — jams, cities, even economies — working on scales of space and time far beyond our ability to map. Now let’s talk about ants.”

That had come out of left field. “From cities to ants?”

“What do you know about ants?”

“Nothing,” I said. “Except that they are persistent buggers when they get into your garden.”

“Ants are social insects — like termites, bees, wasps. And you can’t get them out of your garden because social insects are so bloody successful,” he said. “There are more species of ant in a square mile of Brazilian rain forest than there are species of primate across the planet. And there are more workers in one ant colony than there are elephants in all the world …”

“You’ve been on the Internet again.”

He grinned. “All human wisdom is there. Everybody knows about ant colonies. But most of what everybody knows is wrong. Only the queen lays eggs, only the queen passes on her genes to the next generation. That much is true. But you probably think that an anthill is like a little city, with the queen as a dictator in control of everything.”

“Well—”

“ Wrong. George, the queen is important. But in the colony, nobody knows what’s going on globally — not even the queen. There’s no one ant making any decisions in there about the destiny of the colony. Each one is just following the crowd, to build a tunnel, shift more eggs, bring back food. But out of all those decisions, the global structure of the colony emerges. That social scaling-up, by the way, is the secret of the social insects’ success. If a solitary animal misses out a task, it doesn’t get done. But with the ants, if one worker misses a task somebody else is sure to come along and do it for her. Even the death of an individual worker is irrelevant, because there is always somebody to take her place. Ant colonies are efficient .

“But it is the colony that counts, not the queen. That is the organism, a diffuse organism with maybe a million tiny mouths and bodies … Bodies that organize themselves so that their tiny actions and interactions add up, globally, to the operation of the colony itself.”

“So an anthill is like a traffic jam,” I guessed. “Emergent.”

“Yes. Emergence is how an anthill works. Now we have to talk about genes, which is why it works.” He was off again, and I struggled to keep focused.

“Social insects have three basic characteristics.” He ticked the points off on his fingers. “You get many individuals cooperating in caring for the young — not just parents, as among most mammals, say. Second, there is an overlap of generations. Children stay at home to live with their parents and grandparents. Third, you have a reproductive division of labor—”

“Neuters,” I said.

“Yes. Workers, who may remain sterile throughout their lives, serving the breeders …”

I started to get a sense of where he was going. I didn’t want to hear it. Dread gathered in the pit of my stomach. I pulled on the beer, drinking too fast. When I came back to George, he was talking about Darwin.

“… Darwin himself thought ants were a great challenge to his theory of evolution. How could sterile worker castes evolve if they leave no offspring? I mean, the whole point of life is to pass on your genes — isn’t it? How can that happen if you’re neuter? Well, in fact, natural selection works at the level of the gene , not the individual.

“If you’re a neuter, you give up your chance of having daughters, but by doing so you help Mom produce more sisters. Why do you do it? Because it’s in your genetic interests. Look, your sisters share half your genes, because you were born from the same parents. So your nieces are less closely related to you than your own daughters. But if, by remaining celibate, you can double the numbers of your nieces, you gain more in terms of genes passed on. In the long term you’ve won the genetic lottery.