Lesotho is a small country of mountain ranges and rivers. It has the highest average of elevation in the continent and would have been a formidable place for hunter-gatherers to live, Stewart says. But the fresh water coursing through the country and belts of resources, stratified by the region’s elevation, provided protection against swings in climate for those who lived there, as early as 85,000 years ago.
…In Lesotho, archeologists began finding small ornaments made of ostrich eggshell. But ostriches don’t typically live in that environment, and the archeologists didn’t find evidence of those ornaments being made in that region—no fragments of unworked eggshell, or beads in various stages of production.
So when archeologists began discovering eggshell beads without evidence of production, they suspected the beads arrived in Lesotho through these exchange networks.
…Brian Stewart and colleagues establish that the practice of exchanging these ornaments over long distances spans a much longer period of time than previously thought.
…”These ornaments were consistently coming from very long distances,” Stewart said. “The oldest bead in our sample had the third highest strontium isotope value, so it is also one of the most exotic.”
Stewart found that some beads could not have come from closer than 325 kilometers from Lesotho, and may have been made as far as 1,000 kilometers away. His findings also establish that these beads were exchanged during a time of climactic upheaval, about 59 to 25 thousand years ago. Using these beads to establish relationships between hunter-gatherer groups ensured one group access to others’ resources when a region’s weather took a turn for the worse.
…”These exchange networks could be used for information on resources, the condition of landscapes, of animals, plant foods, other people and perhaps marriage partners.”