A team of researchers has found the oldest molecular genetic evidence of a nuclear family, in one of four graves dating back about 4,600 years to the Stone Age. Using DNA analysis, the researchers identified the remains in one grave as a mother, father, and two sons ages 8 or 9 and 4 or 5. A second grave contained three children, two of which who had the same mother, though they are buried with another woman, likely a paternal aunt or possibly a step-mother. In total, the remains of 13 people were found, all of whom were interned at the same time.
Evidence—like a stone projectile point found embedded in the vertebra of one female and the defense injuries to the forearms and hands found on several of the bodies—suggest that the community was violently attacked by another group. It's believed that those who survived the raid later returned and, using their knowledge of the familial bonds among the dead, took great care to bury the dead according to their relationships in life. Several pairs were arranged face to face, with their arms and hands linked.
The graves were discovered at the early farming site of Eulau in Germany. Before humans began to farm, which caused them to stay in one place, they lived as nomadic hunters and gatherers—and the basic unit of social organization, anthropologists believe, was not the nuclear family, but rather the band or tribe. "By establishing the genetic links between the two adults and two children buried together in one grave, we have established the presence of the classic nuclear family in a prehistoric context in Central Europe—to our knowledge the oldest authentic molecular genetic evidence so far," says Wolfgang Haak of the Australian Centre for Ancient DNA at the University of Adelaide, who led the study published in the Proceedings of the National Academy of Sciences. "Their unity in death suggests a unity in life. However, this does not establish the elemental family to be a universal model or the most ancient institution of human communities." —Heather Wax