Imagine a checkerboard world. Black and white squares, going on and on until they wrap around into a sphere. Imagine the white places are water, the square spaces land. The land/squares are homogenous. They have similar resources, similar surface features, similar size (except that, the closer one approaches the poles, the smaller the “squares” become (because, of course, they are not really square, existing in three dimensions as they do. For the sake of this “thought experiment,” assume that the climate is as hospitable in the polar regions as in the equatorial and resources are equally distributed.
Image created by Bing Image Creator.
Now, plant a human colony on one of these “squares.” A hundred people, men and women, are starting life anew on this imagined world. Leave them alone for a dozen or so generations. Then come back to check on them. What will have happened? As the population has grown, how has it spread? Is the population equally distributed from one square to the next or are populations concentrated in some regions and widely scattered—or completely absent—from others. Do the more numerous and scattered people continue to speak the language of their ancestors or has the language evolved? As the language evolved, do all of the squares have the same language or have the squares developed their own languages, their own national identities, their own religions even? Do they live cooperatively together, or do they make war against their neighbors on different squares. Do they try to conquer and enslave one another or
Imagine what human settlement and diversity would look like on our imaginary checkerboard world. Because the squares are all similar—though the squares near the equator will, necessarily, be larger than the ones near the poles—and because we could imagine that each square will be endowed with characteristics similar to their neighbors—the same resources, same mountains, same climate patterns . . . and because moving from square to square is simply a matter of crossing diagonally from one square to another (rather like a bishop moves across a chessboard) we might decide that the cultures on our imagined planet are all quite homogenous. Or not. Living peaceably together. Or not.
Back to earth.
The surface of Planet Earth, as we experience it, is the result of 4.5 billion years of physical and biological forces that allowed continents to slowly re-arrange themselves, mountains to emerge and, ever so slowly, erode into hills, and oceans to fill in the spaces between the continents. Over the last few hundred thousand years, people have made their homes on the planet’s surface, learned to travel over the oceans, and found their lives shaped by the physical nature of the landscape they find themselves inhabiting. People on earth, though once few in number and presumably homogenous, have evolved myriad languages, cultural patterns, political identities, and systems of distribution.
People on earth have identified some people as their neighbors—especially if they shared common cultural patterns and ways of thinking. Others have been identified as, well, The Other. Not like Us. Different. Not my neighbor. People on earth have, with rare exceptions, been aware of the existence of “people not like us” and have had contact with them—trading, exchanging marriage partners, tolerating, conquering, or exterminating the “others.”
When people of one culture encounter people of another culture, stuff happens.
People living in cultural isolation—isolated from contact with other human cultures in an environment that has not experienced dramatic change—will tend to change very slowly if at all. Isolated tribal groups in the Amazon Basin, Central Africa, and elsewhere, may continue to hunt and gather, or practice small-scale agriculture, much as their ancestors have done for millennia.
Such groups usually do not do well when they first come into contact with technologically more “advanced” cultures. Sometimes, the “indigenous” communities were exterminated or to make way for (usually) European settlement or enslaved to provide labor for those same settlers.. More often, indigenous people who encountered more powerful outsiders adapted themselves to the newcomers, welcoming the new technologies and the seeming advantages they brought, and even adopting new religious and cultural ideas.
So pervasive have these processes been, that in the 21st century, hardly any un-contacted, indigenous communities continue to exist. Those who continue to practice their traditional lifestyles tend to do so in the margins of “modern” civilization and usually with the sufferance of the governments that claim sovereignty over the indigenous people’s territory.