A number of factors account for Americans’ mobility. The principle reason for moving is employment: people move to find work and support themselves, a rationale understandable to any hunter-gatherer. Interestingly, people who earn more move more. Only 25% of Americans with household incomes of $100,000 or more live in the community where they were born. Similarly, more educated Americans have moved more, going away to college and then moving on to pursue jobs.
The young move more than the elderly. Westerners move more than Midwesterners. When Americans move, they tend to head south.
These patterns of mobility in the United States are not shared by other industrialized nations. Overall, Europeans move about half as much as Americans.9 While mobility in the United Kingdom and the Scandinavian countries approaches the American pace, in other nations—such as Italy, Portugal, Greece, and Ireland—less than 5% of the population moves annually.
So despite a decrease in mobility over the last sixty years, Americans still move a lot. Which you would think would mean that we would have less stuff.
But if you have moved recently, you know that isn’t true.
. . .
The prehistoric shift to permanent dwellings and settled villages occurred after 18,000–15,000 years ago, but at various times in different places for distinct reasons. In southwestern Japan in southern Kyushu, summer villages and winter villages existed by 13,500 years ago. These were the prehistoric forebears of a durable cultural tradition known as Jomon.10 The Jomon tradition lasted for approximately 10,000 years, the name (“cord-marked”) associated with the distinctive pottery with its twine-stamped exterior, some of the earliest ceramic vessels known in the world. Initially recognized from its pottery, more recent archaeological research has pushed knowledge of Jomon back in time to its pre-ceramic antecedents.
The origins of sedentism in Japan is nuts. Quite literally nuts, because the diet was based on acorns, beechnuts, walnuts, buckeyes, and chestnuts. Previously, Paleolithic foragers had used stone mortars, pestles, and hammer-stones to crack and pulverize nuts to supplement their diets. But as climate warmed and deciduous broadleaf groves replaced conifer forests, nuts became staples in ancient Japanese cuisine.11
The earliest Jomon houses were pit-houses or tents associated with other features that suggested a prolonged stay. Special hearths with sloping underground flues may have been used to smoke meat. Heavy grinding stones—some weighing more than 85 pounds—indicate sustained encampments.
Even more substantial and permanent communities developed by 13,000 years ago. For example, the site of Uenohara contains one area—Sector 4—that was the largest known Japanese settlement of its time. Spread over 13,000 square meters, the site has 52 house pits, a dozen of which were occupied at a single time during the four different phases in the hamlet’s history. The houses were roughly rectangular, approximately 3 × 5 meters in area, and some of the dwellings had ventilated hearths. In addition to the houses, storage pits and networks of paths indicate that Uenohara was a permanent Jomon village, inhabited until 12,800 years ago when it was covered by ash and cinders from a nearby volcano’s eruption.
Despite this volcanic setback at Uenohara, over subsequent millennia sedentary life was fundamental to Jomon culture. Throughout the Japanese archipelago, the number of Jomon sites increased through time with population peaking after 5000 B.C. during the Middle Jomon period. Houses became more substantial, especially in the cooler northern islands.
Given the Jomon tradition’s long duration, it is not surprising that settlements would vary in size and composition. But most known Jomon sites are small; most Jomon houses are tiny. In part, these limits were not a mark of failure, but an index of sustainability. Bigger is not always better.
Located in the middle of the bustling port city of Aomori on the northern tip of Honshu, the site of Sannai Marayama is the largest known Jomon site.12 Discovered in the mid-1990s during a construction project, the site was excavated and then preserved as a major cultural center. More than 600 buildings have been uncovered at Sannai Marayama, dating over 12 phases between 3900 and 2300 B.C. Most of these houses were small pit houses and rectangular raised dwellings less than 5 meters long. A few much larger buildings were constructed, a couple of them 23–32 meters long, but it is unclear what these structures were or exactly how long they were occupied.
FIGURE 6. Reconstructions of Jomon houses at Sannai Maruyama.
In the case of the Jomon, it was not the sheer abundance of food that allowed for larger and more permanent homes and hamlets. Rather, it was the timing and location of foods that selected for those human responses. Acorns, chestnuts, buckeyes, and walnuts were harvested in the fall, stored in pits, and eaten throughout the winter. Fall was also the time for fishing for migrating salmon, hunting fat deer, and—in general—preparing stored foods for winter.13
Such a diet tends to select for sedentary life, especially when different habitats are relatively close. Living near the ocean in a delta crossed by rivers and streams and with densely forested hills and mountains only 5–10 kilometers to the south, the people of Sannai Marayama were ideally positioned to take advantage of rich natural resources. Similar factors account for Jomon sedentism through much of the Japanese archipelago.
And that explains the successful growth of the community—until it grew just a little too big.
The excavations uncovered a complex history of ancient Japanese homes. For much of its history, Sannai Marayama was a modest village, larger than Uenohara, but usually with fewer than 50 dwellings, housing 200–300 people. In the middle of the Middle Jomon, however, the settlement experienced a building boom, growing into a large village of 200 houses. But after reaching this peak population, Sannai Marayama withered in size, reverting to a modest village of people living in small huts.
What happened?
Junko Habu, an archaeologist from the University of California, Berkeley, who has excavated at Sannai Marayama, argues that the site’s population grew to unsustainable levels. Because of poor preservation, ancient plant and animal remains were unevenly preserved at the site. In order to gain an indirect insight into subsistence at Sannai Marayama, Habu analyzed in great detail the different stone tools used in hunting, gathering, and food preparation (like inferring dietary differences based on the ratios of salad forks to steak knives in a vegan’s and a meatlover’s respective kitchens).
Habu’s analysis pointed to major shifts in subsistence over time. Beginning with the Early Jomon levels, the relative number of grinding stones increased, until peaking in the early phases of the Middle Jomon, when these tools used for grinding plants comprised 80% of all the stone tools. Then the pattern changed calamitously: the percentage of grinding tools was halved and arrowheads became the most common stone tool. The preponderance of arrowheads marked an increased emphasis on hunted game rather than collected plant foods.
Habu argues that the people of Sannai Marayama were victims of overspecialization. When hunters and gatherers are mobile, they usually collect and hunt a wide array of plants and animals. When hunters and gatherers become more sedentary, they become more specialized. The people of Sannai Maruyama could no longer be sustained by wild plant foods. Adjustments were critical. People first tried to make up for lost calories by hunting more; that was not enough. The community inevitably declined. Ultimately Jomon hunting and gathering—a supremely successful adaptation for more than ten thousand years—gave way to village life based on cultivating rice.
This is one of the fundamental lessons from the past. Human communities may evolve extraordinarily successful ways of life, but they do this by making specific choices with often unforeseen consequences. In the process, the range of possible options inevitably narrows, which presents a problem