stable isotope levels, eight Cobern Street Burial Ground individuals consumed a diet based on C4 (tropical) plants in childhood, then consumed more C3 plants, which were more common at the Cape later in their lives. Six of these individuals had dental modifications similar to those carried out by peoples inhabiting tropical areas known to be targeted by slavers who brought enslaved individuals from other parts of Africa to the colony. Based on this evidence, it was argued that these individuals represent enslaved persons from areas of Africa where C4 plants are consumed and who were brought to the Cape as laborers. These individuals were not assigned to a specific ethnicity, but it is pointed out that similar dental modifications are carried out by the Makua, Yao, and Marav peoples. Four individuals were buried with no grave goods, in accordance with Muslim tradition, facing Signal Hill, which is a point of significance for local Muslims. Their isotopic signatures indicate that they grew up in a temperate environment consuming mostly C3 plants, but some C4 plants. Many of the isotopic signatures of interred individuals indicate that they Cox et al. argue that these individuals were from the Indian Ocean area. They also suggest that these individuals were Muslims. It was argued that stable isotopic analysis of burials, combined with historical and archaeological data can be an effective way in of investigating the worldwide migrations forced by the African Slave Trade, as well as the emergence of the underclass and working class in the colonial Old World. Nitrogen The nitrogen stable isotope system is based on the relative enrichment or depletion of 15N in comparison to 14N in an analyzed material (δ15N). Carbon and nitrogen stable isotope analyses are complementary in paleodiet studies. Nitrogen isotopes in bone collagen are ultimately derived from dietary protein, while carbon can be contributed by protein, carbohydrate, or fat in the diet. δ13C values help distinguish between dietary protein and plant sources while systematic increases in δ15N values as you move up in trophic level helps determine the position of protein sources in the food web. 15N increases about 3-4% with each trophic step upward. It has also been suggested that the relative difference between human δ15N values and animal protein values scales with the proportion of that animal protein in the consumer's diet, though this interpretation has been questioned due to contradictory views on the impact of