Researchers from the Department of Archaeology at the Max Planck Institute for the Science of Human History have discovered evidence of a vast social network that existed between 33,000 and 50,000 years ago in eastern and southern Africa, in the form of beads made from ostrich egg shells.
The network is the oldest social network yet discovered, according to the Planck Institute.
The study, conducted by Jennifer Miller from the University of Alberta's Department of Anthropology and Yiming Wang, both archaeologists at the Max Planck Institute, was published in December in the peer-reviewed journal Nature Communications.
Though it has already been revealed through genetic analyses that early humans in eastern and southern Africa split apart in the Pleistocene epoch, between 70,000 and 350,000 years ago, the social relationships between them and how they split are not fully understood.
The Planck Institute researchers, however, deduced from similarities in the ostrich beads that a network measuring over 3,000 kilometers once existed in eastern and southern Africa.
“Throughout the 50,000 years we examined, this is the only period the bead characteristics are the same,” Wang said.
Furthermore, changes in climate have been linked to population connection and divergence, so in order to determine the effects of climate on the homo sapien population in eastern and southern Africa during the Late Pleistocene, the researchers compared the characteristics of the ostrich shell beads with shifts in the region's climate.
The results suggested that the divergence of this population coincided with a period during which there was increased rainfall in the area, flooding riverbanks and likely creating a barrier that caused the social network to split.
The study sheds new light on early human social behavior and the effects of climate change on human populations.
"These tiny beads have the power to reveal big stories about our past," Miller said. "We encourage other researchers to build upon this database, and continue exploring evidence for cultural connection in new regions."