Flavouring food: the contribution of chimpanzee behaviour to the understanding of Neanderthal calculus composition and plant use in Neanderthal diets

In a recent study, Hardy et al. (2012) examined ten samples of dental calculus from five Neanderthal individuals from El Sidrón in northern Spain (occupation dates between 47300 and 50600 BP). In calculus from a young adult, they discovered the presence of compounds (dihydroazulene, chamazulene and methylherniarin) that occur in yarrow (Achillea millefolium) and camomile (Matriarca chamomilla). In preference to other hypotheses, the authors proposed that these two plants were used for self-medication. In this paper, we do not reject the self-medication hypothesis, but our observations of wild chimpanzees in Uganda, at Sonso in the Budongo Forest Reserve and at Kanyawara and Sebitoli in Kibale National Park (separated by about 150km), as well as ethnological and palaeontological evidence, lead us to propose three other explanations for the presence of these compounds. In addition, data on Neanderthal behaviour suggest that their subsistence and technological strategies were complex.

Crop-raiding deterrents around Budongo Forest Reserve: an evaluation through farmer actions and perceptions

Crop-raiding by primates and bushpigs Potamochoerus porcus is a major cause of human–wildlife conflict around Budongo Forest Reserve, Uganda. In 2006–2007 a project was initiated, with farmer participation, to investigate the efficacy of on-farm techniques to reduce crop-raiding, including guarding and early-warning techniques, fences, plant barriers, trenches, lights and nets. Here, farmers' perceptions of the effectiveness and sustainability of these deterrents were evaluated using semi-structured interviews and direct observations. Factors important to farmers in effective, sustainable and locally appropriate crop-raiding mitigation are that deterrents be cost-effective, easily manipulated, improve guarding efficiency and require minimal labour inputs. Farmers reported paid guards, guard dogs, wire fences, lights and bells/alarms as most effective. This differs from observations that farmers independently maintained certain deterrents that they presumably considered valuable, namely wire fences, guard dogs, bells/alarms, trenches, lights and nets. This evaluation demonstrates the importance of farmers' participation and perceptions in the viability and uptake of crop-raiding deterrents, and the importance of assessing conflict mitigation trials over the long term.