Do class divisions go all the way back to the Stone Age?

Figuring out exactly when people started to separate into different social strata is one of the tricky, nebulous areas of archaeological research. When and why did humans move from egalitarianism to inherited land, wealth, and power?

And now, new evidence suggests that we already had social classes as long ago as 7,000 years ago, in the midst of the stone age.

Top image: Cover art from Land of the Painted Caves by Jean M. Auel.

Research published this week in PNAS has found evidence of social stratification and hereditary inequality in central Europe from around 5,500BCE.

This evidence comes from analyzing the strontium 86/87 isotope ratios in the teeth of human remains — which serves as a geological signature of the location of someone's childhood. What the researchers found was that females moved around more than males, and males buried with stone adzes moved less than those without, and were more associated with the fertile loess areas of the countryside.

There are a number of ways that this data could be interpreted — that the men without adzes moved for marriage, or weren't farmers. But the way that seems to agree most directly with the archaeological evidence is that of a patrilocal kinship system, where women moved for marriage, and families of men stayed in the same place, retaining access to, and inheriting, the same lands.

It's the earliest statistical evidence for people maintaining the wealth and land of their forefathers, and it shows it was happening long before lavish burials for wealthy people made it obvious.