Earliest evidence for the ivory trade in southern Africa : isotopic and ZooMS analysis of seventh-tenth century AD ivory from KwaZulu-Natal

KwaGandaganda, Ndondondwane and Wosi were major Early Farming Community settlements in what is today the KwaZulu-Natal province of South Africa. These sites have yielded, among other remains, abundant evidence of ivory and ivory working dating to the seventh–tenth centuries ad, pre-dating by approximately 200 years the better-known ivory artefacts from sites in the Limpopo River Valley and surrounding regions. We report the results of carbon, nitrogen and strontium isotope analysis to explore the origins and procurement of this ivory, in combination with Zooarchaeology by Mass Spectrometry (ZooMS) to identify the species of animals from which it was derived. All of the ivory studied using ZooMS was elephant, despite the presence of hippopotamus remains on all three sites. Some ivory was probably obtained from elephant herds that lived close to the sites, in the densely wooded river valleys favoured by both elephants and early farmers. Other material came from savannah environments further afield. Ivory found at these three sites was drawn from different catchments, implying a degree of landscape/resource partitioning even at this early stage. These communities clearly invested substantial effort in obtaining ivory from across the region, which speaks to the importance of this commodity in the economy of the time. We suggest that some ivory items were for local use, but that some may have been intended for more distant markets via Indian Ocean trade

Dynamics of births and juvenile recruitment in Mara-Serengeti ungulates in relation to climatic and land use changes

Natality and recruitment govern animal population dynamics, but their responses to fluctuating resources, competition, predation, shifting habitat conditions, density feedback and diseases are poorly understood. To understand the influences of climatic and land use changes on population dynamics, we monitored monthly changes in births and juvenile recruitment in seven ungulate species for 15 years (1989-2003) in the Masai Mara Reserve of Kenya. Recruitment rates declined for all species but giraffe, likely due to habitat alteration and increasing vulnerability of animals associated with recurrent severe droughts, rising temperatures, unprecedentedly strong and prolonged El Nio-Southern Oscillation (ENSO) episodes, expansion of settlements, cultivation and human population growth in pastoral ranches adjoining the reserve. Birth rate showed strong and humped relationships with moving averages of monthly rainfall, whereas recruitment responded strongly to cumulative past rainfall. Increasing livestock incursions into the reserve depressed recruitment rate for quarter-grown topi. Expansion of pastoral settlements depressed birth rate in impala, zebra and giraffe. Frequent ENSO-related droughts caused progressive habitat desiccation and hence nutritional shortfalls for ungulates. The responses to climatic, land use and resource influences did not reflect body size, migratory or resident lifestyle, dietary guild, digestive physiology or degree of synchrony of breeding of the ungulate species