Since the beginning, people have sparked bouts of globalization by picking up stakes and moving. As migrants rubbed shoulders - sometimes peacefully, sometimes not - they changed cultures and history. The current round of globalization could well speed up these socio-demographic forces.
But the process is never simple and contains enough twists and turns to keep historians guessing for some time to come. Globalization could just as easily end up slowing the world's march toward big cities.
Although men and women have been heading to cities ever since civilization began, urbanization didn't amount to much until the Industrial Revolution. Even as late as 1850 in Europe, only 11 percent of the population lived in cities. But as factories needed hands to run the machines, rural people responded.
City jobs meant more income - even if city life remained squalid and less healthy until the 20th century, when public sanitation began to take hold in earnest. Today, three-quarters of the population in developed countries make their homes in the city - and now live longerthan their rural counterparts. By 2005, according to United Nations' projections, half of all the world's population will be urbanized.
This move from farm to city transforms life and culture. Sometimes, surprisingly so. For example, demographers believe urbanization convinced families to have fewer children. No longer needed for farm chores, city children proved expensive to house and feed. Urban families began to cut back on the number of children they had, investing more in each one, particularly in their education.
That pattern packs huge cultural implications. Already, almost every industrialized nation faces population stagnation or outright decline in the coming decades. By 2050, according to the UN's moderate scenario, Europe's 729 million population will shrink by 100 million. It's not clear which will have the greater cultural impact: a world with fewer Europeans (down from a 12 percent share now to 7 percent in 2050) or a world with much better educated ones.
As other countries develop, demographers believe they too will follow a similar path and world population growth will begin to slow.
A big population has never determined a nation's geopolitical power, historians and demographers agree. Technology, military power, and industrial might play more important roles. But without big numbers of people, they add, it's harder to keep one's seat at the table of great powers.
The US remains the exception to Western population decline. Already industrialized, it is projected to continue growing from 276 million to just under 350 million by 2050 and maintain its rank as the world's third-largest nation. The key is immigration, which has long played an important role in America's growth.
For example: While the population of Europe more than doubled between 1800 and 1900, North America grew nearly 12-fold. The process wasn't always pretty or voluntary. From the 17th to the 19th centuries, slavers brought in an estimated 15 million Africans to the Americas. As whites pushed into the interior, they brought epidemics and weapons that decimated indigenous populations.
Many populations in Latin America collapsed as Spain consolidated control. So did native Americans in the US.
Will immigrants keep coming here in the 21st century? The globalization of media and communications technology suggests that, more than ever, the world's poor know how people in rich countries live. Those images could prove a powerful lure.
On the other hand, the globalized technology may bring jobs to the world's rural people and no longer force them to move to rich countries for employment. Should that happen, it would mark a sea change in the movement of people and unleash new social and cultural forces in a world that never tires of transformation.
(c) Copyright 2001. The Christian Science Monitor