Geo-ethnoarchaeology of pastoral sites: The identification of livestock enclosures in abandoned Maasai settlements

The earliest food producers in Africa were mobile pastoralists who left limited archaeological traces. As a result archaeologists studying the spread of food production in the region have difficulty distinguishing early pastoralists from hunter-gatherers with whom they interacted. This geo-ethnoarchaeological study contributes to the resolution of the problem through identification of sediments distinctive of livestock enclosures, and thus of pastoral settlements. Sediments were sampled in and around currently occupied and recently abandoned Maasai livestock enclosures ranging in age between one and 40 years. Twenty to thirty years after site abandonment, there is no visible difference between enclosure and regional sediments. Micromorphological, mineralogical, and phytolith analyses, of enclosure sediments, however, allow differentiation of enclosure from regional sediments. Our results show that a unique undulating microlaminated structure is distinctive of enclosure sediments. Enclosure sediments, especially small stock, also contain a rare mineral, monohydrocalcite (CaCO₃ . H₂O). In addition, large amounts of opal (SiO₂ . nH₂O), in the form of phytoliths, are found in enclosure relative to regional sediments. These differences are likely to be preserved in the archaeological record, and this approach will allow better understanding of the spread of pastoralism in Africa and elsewhere.