THE UTILISATION OF GRASS SEEDS FROM HARVESTER ANT NESTS IN NORTHWEST NAMIBIA

摘要

In her discussion on the evidence for the use of grass seeds as a subsistence resource, Nic Eoin (2016) unfortunately makes no reference to well documented anthropological and ethnoarchaeological observations from arid northwest Namibia (Vedder 1928; Jacobson 1981, 1984, 2004/5; du Pisani 1978; Inskeep 2003; Steyn & du Pisani 1985; Sullivan 1999). These observations focus on the collection of grass seeds from the nests of harvester ants (Messor sp.) by the Damara communities living in the area. Although precipitation in the Namib is highly seasonal, cyclical and patchy with an average yearly precipitation ranging from less than 200 mm in the proNamib transition zone to less than 50 mm in the Namib, it only takes 21 mm of rain to produce a standing crop of grass (Sealy 1978) that for a short space of time resembles a grassland environment. In the past, this seasonal bounty of fresh grazing attracted game from the interior (Martin 1974; Jacobson 1984, 2014) as well as hunter-gatherers and pastoralists (Jacobson 1984). Ants harvested kilograms of seeds and stored them in underground chambers. In an experiment I carried out with two assistants, we found and collected 2.5 kg of seed in approximately two hours. There were two dominant seed types, a white seed from grasses mainly Stipagrostis spp, saun, and a red seed from Monsonia umbellata, bosui (see Jacobson 1981: fig. 9; Jacobson 2004/5: fig. 1; Sullivan 1999: figs 2 &3). Additional species are listed in Sullivan (1999,2005) and Steyn & du Pisani (1985).