At Home - Bill Bryson [18]
The important thought to hold on to is that for the first 99 percent of our history as beings we didn’t do much of anything but procreate and survive. Then people all over the world discovered farming, irrigation, writing, architecture, government, and the other refinements of being that collectively add up to what we fondly call civilization. This has been many times described as the most momentous transformation in human history, and the first person who fully recognized and conceptualized the whole complex process was Vere Gordon Childe. He called it the Neolithic Revolution.
It remains one of the great mysteries of human development. Even now scientists can tell you where it happened and when, but not why. Almost certainly (well, we think almost certainly), it had something to do with some big changes in the weather. About twelve thousand years ago, the Earth began to warm quite rapidly; then for reasons unknown it plunged back into bitter cold for a thousand years or so—a kind of last gasp of the ice ages. This period is known to scientists as the Younger Dryas. (It was named for an arctic plant, the dryas, which is one of the first to recolonize land after an ice sheet withdraws. There was an Older Dryas period, too, but it wasn’t important for human development.) After ten further centuries of biting cold, the world warmed rapidly again and has stayed comparatively warm ever since. Almost everything we have done as advanced beings has been done in this brief spell of climatological glory.
The interesting thing about the Neolithic Revolution is that it happened all over the Earth, among people who could have no idea that others in distant places were doing precisely the same things. Farming was independently invented at least seven times—in China, the Middle East, New Guinea, the Andes, the Amazon basin, Mexico, and West Africa. Cities likewise emerged in six places—China, Eygpt, India, Mesopotamia, Central America, and the Andes. That all of these things happened all over, often without any possibility of shared contact, seems uncanny. As one historian has put it: “When Cortés landed in Mexico he found roads, canals, cities, palaces, schools, law courts, markets, irrigation works, kings, priests, temples, peasants, artisans, armies, astronomers, merchants, sports, theatre, art, music, and books”—all invented quite independently of similar developments on other continents. And some of it is a little uncanny, to be sure. Dogs, for instance, were domesticated at much the same time in places as far apart as England, Siberia, and North America.
It is tempting to think of this as a kind of global lightbulb moment, but that is really stretching things. Most of the developments actually involved vast periods of trial, error, and adjustment, often over the course of thousands of years. Agriculture started 11,500 years ago in the Levant, but 8,000 years ago in China and only a little over 5,000 years ago in most of the Americas. People had been living with domesticated animals for 4,000 years before it occurred to anyone to put the bigger of them to work pulling plows; Westerners used a clumsy, heavy, exceedingly inefficient straight-bladed plow for a further 2,000 years before someone introduced them to the simple curved plow the Chinese had been using since time immemorial. Mesopotamians invented and used the wheel, but neighboring Egypt waited 2,000 years before adopting it. In Central America, the Maya also independently invented the wheel but couldn’t think of any practical applications for it and so reserved it exclusively for children’s toys. The Incas didn’t have wheels at all, or money or iron or writing. The march of progress, in short, has been anything but predictable and rhythmic.
For a long time it