The world’s oldest fully manufactured ornaments are ostrich eggshell beads.

Different cultures produced beads of different styles,. With this knowledge researchers are able to trace cultural connections thousands of years ago.

Data was looked at from more than 1500 individual beads unearthed from 31 sites across southern and eastern Africa, encompassing the last 50,000 years, by scientists from the Max Planck Institute for the Science of Human History .

Drs. Jennifer Miller and Yiming Wang  found that between 50,000 and 33,000 years ago, people in eastern and southern Africa were using nearly identical OES beads. The finding suggests a long-distance social network spanning more than 3,000 km once connected people in the two regions.

Dr Wang explained:

“The result is surprising, but the pattern is clear. Throughout the 50,000 years we examined, this is the only time period that the bead characteristics are the same.”

This eastern-southern connection at 50-33,000 years ago is the oldest social network ever identified, and it coincides with a particularly wet period in eastern Africa.

Signs of the regional network disappear by 33,000 years ago, likely triggered by a major shift in global climates. Around the same time that the social network breaks down, eastern Africa experienced a dramatic reduction in precipitation as the tropical rain belt shifted southward. This increased rain in the large area connecting eastern and southern Africa (the Zambezi River catchment), periodically flooding riverbanks, and perhaps creating a geographic barrier that disrupted regional social networks.

The results of this work document a 50,000-year-long story about human connections, and the dramatic climate changes that drove people apart. The data even provides new insight into variable social strategies between eastern and southern Africa by documenting different bead-use trajectories through time. These regional responses highlight the flexibility of human behavior and show there’s more than one path to our species’ success.

Dr Miller said:

“These tiny beads have the power to reveal big stories about our past. We encourage other researchers to build upon this database, and continue exploring evidence for cultural connection in new regions.”

The results, Ostrich eggshell beads reveal 50,000-year-old social network in Africa, have been published in the journal Nature.