The foodplant fitness landscape of Wonderboom and possible implications for Middle Pleistocene foragers of the Magaliesberg, South Africa

Abstract

With this contribution, we provide a species and edible part list for the foodplant population of the Wonderboom landscape at the eastern end of the Magaliesberg range in Gauteng, South Africa, as a current proxy to hypothesise about past foraging behaviours. The greater Magaliesberg region is an ancient, relatively stable ecotone between the Grassland and Savanna Biomes, with its roots in the plateau uplift at ~ 4 Ma. We present the foraging landscape (foraging-scape) in a three-tier model at intervals of ~ 12.5 km, ~ 35 km, and ~ 70 km to assess proportional increases in foodplant species and edible parts when the foraging range is increased. We demonstrate that foraging within a ~ 12.5 km radius from the site provides an exceptionally rich foodplant landscape today. Thus, if the foodplant fitness potential during the Middle Pleistocene was roughly similar, it is reasonable to hypothesise that the Wonderboom foragers may have had little reason—apart from perhaps famine or drought—to go beyond a daily range for collecting plant foods. The Wonderboom ~ 12.5 km radius surface area is broadly similar to the footprint of the Cradle of Humankind ~ 40–70 km to its southwest. Directly comparing their foodplant species inventories shows that currently, 185 more foodplants grow around Wonderboom than in the Cradle. Our results suggest that the ecotone locality of Wonderboom, between the Grassland Biome to the south and the Savanna Biome to the north, may have had adaptive advantages in terms of its foodplant foraging potential.