It’s not hard to tell rich neighborhoods from poor neighborhoods. Wealthy parts of town generally have nicer cars, clean, well-groomed lawns, and, most strikingly, giant sprawling mansions. It’s nothing new: across cultures, wealth and power have been tied to large homes for thousands of years.
A group of scientists, including Field Museum anthropology curator Gary Feinman, recently explored the link between house sizes and inequality. Based on a sample of more than 60 cases, they discovered that on the whole, patterns of inequality in Eurasia over time were greater than found for North and Middle America, and that the presence of large domesticated animals in the former region may be a contributing factor to the history of wealth differences in the Old and New Worlds.
“This is the first step towards quantifying the extent of inequality in the deep past,” says Feinman in a paper recently published in Nature. “It allows us to put contemporary growth of inequality into a broader historical context.”
To determine the amount of social and economic inequality of different societies, the team examined data from 63 archaeological cases and compared the sizes of the houses in each of those contexts. They then assigned measures of inequality called Gini coefficients to compare the levels of inequality in different societies. A society with perfectly equal distribution of wealth would have a Gini coefficient of 0, and a society where one household has all the wealth would get a 1.
The researchers were surprised by a pattern they saw in the data. For the cases from Europe and Asia, levels of inequality kept rising over time, but for the societies in the Americas, inequality levels plateaued. The suspected factor: Eurasia’s draft animals like cattle, horses, and water buffalo.
Draft animals let farmers till more land with less labor, which ultimately allowed a smaller number of farmers to amass a disproportionate amount of wealth. The Americas did not have large domesticated animals during the time periods the researchers looked at, so these societies did not show consistent evidence of mounting inequality.
“If you have a herd of horses, you do not need a lot of labor to maintain them, but they are still a potentially valuable resource for long-distance trade and military raid,” explains Feinman. “Opportunities that yield big rewards and wealth without a heavy dependence on local labor have the potential to make you richer, to concentrate wealth.”
And we can see a similar pattern in the US over the last couple of centuries. When the main industries were farming and manufacturing, wealth was more evenly distributed, since capital was dependent on large supplies of local labor. Such enterprises required a lot of people to get the work done, so the bosses had to treat their workers well enough that they would not quit. Today, there are more jobs in finance and information technology, which require fewer people to get the work done but may be lucrative. That allows a smaller number of people to reap and concentrate profit.
“It’s funny. We think of the United States as a land of equality, but in reality, the most unequal societies in the past were still more equal than the US today,” says Feinman. “The last few decades are when the wealth inequality in the US ballooned, and that’s the same time that you start seeing giant McMansions popping up at a pace not seen in the recent past.”
“Inequality has a lot of subtle and potentially pernicious effects on societies,” says Tim Kohler, a professor of archaeology and evolutionary anthropology at Washington State University and the study’s lead author. “People need to be aware that inequality can have deleterious effects on health outcomes, on mobility, on degree of social trust, on social solidarity—all these things. We’re not helping ourselves by being so unequal.”