Palaeoclimate Reconstruction Using Charcoal from a Mid-Holocene Stratum 4b, Wonderwerk Cave, South Africa

Abstract

Caves are often sources for palaeoenvironmental information in the dry interior regions of southern Africa. The Wonderwerk Cave, located in Northern Cape, is a national heritage site with a well-preserved, nearly complete record of the local Holocene LSA techno-complexes and past environmental indicators. Hence, it has the potential to provide valuable insights into past human behaviour as well as the local palaeoclimate and vegetation. This study examined wood charcoal from stratum 4b, Excavation 1 of the Wonderwerk Cave. The aim was to evaluate the taxonomic composition and the physiognomy of the charcoal to understand the environment around the cave 6.9-5.9 ka. The study also investigated the modern uses of the vegetation to infer how humans may have utilized the woody plants around them during that period. The results indicate the landscape cover included woody plants adapted to dry conditions and summer rainfall. However, the archaeological taxa identified also included two species that thrive in moist environments, Halleria lucida and Olinia ventosa, suggesting fluctuations in climate. The taxonomic composition also suggests an environment similar to the modern bushveld found near the cave. The low conductivity capacity as well as vulnerability and mesomorphy indices of the woods support the implication that the vegetation was adapted to low water availability or aridity. The cave's inhabitants likely used the identified plants for firewood, magical and medicinal purposes, and more between 6.9 and 5.9 ka.