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.

“The numbers are different for ants. The way they pass on their genes is different from mammals — if you’re an ant your sister is actually closer to you genetically than your own daughter! — so they have a predisposition to this kind of group living, which is no doubt why it rose so early and so often among the insects. But the principle’s the same.

“George, an ant colony isn’t a dictatorship, or a communist utopia. It is a family. It’s a logical outcome of high population densities and a hostile external environment. Sometimes it pays to stay home with Mom, because it’s safer that way — but you need a social order to cope with the crowding. So you help Mom bring up your sisters. It’s harsh, but it’s a stable system; emergence makes the colony as a whole work, and there is a genetic payoff for everybody, and they all get along just fine … The biologists call this way of living ‘eusociality’ — eu like in utopia, meaning ‘perfect.’ “

“A perfect family? Now that’s scary.”

“But it’s not like a human family. This genetic calculus doesn’t have much to do with traditional human morality … Not until now,” he said mysteriously. “And it’s not just ants.” He played his trump card. “Consider naked mole rats.”

I had finished the beer. I let Peter call for another one.

Naked mole rats turned out to be spectacularly ugly little rodents — Peter showed me pictures on his handheld — that live in great underground colonies beneath the African deserts. They have bare, unweathered skin, and their bodies are little fat cylinders, to fit into their dark tunnels.

The mole rats’ favorite food is tuber roots, which they have to go dig for. But the roots are widely scattered. So although they are stuck in cramped conditions underground, it is better to produce a lot of little mole rats than a few big ones, because many little helpers tunneling off to find the roots are more likely to succeed than a few.

“Exactly the conditions where you might expect eusociality to develop,” Peter said. “A situation where you’re forced to live with high population density, limited resources …”

Mole rats live in great swarms — and in each colony, of maybe forty individuals, at any one time there is only one breeding pair. The other males simply keep zipped up, but the other females are functionally sterile. They are kept that way by behavior, by bullying from the “queen.”

The workers even have specialized roles — nest building, digging, transporting food. A mole rat will go through several roles as she ages, gradually moving outward from the center. “Some of the ants are like that,” Peter said. “The young serve inside the nest, where they do such chores as nest cleaning. When they get older they serve outside, maybe constructing or repairing the nest, or foraging for food …”