Diet in Peru's Pre-Hispanic Central Coast.

The Tablada de Lurín cemetery (200 BC – AD 200; Lima, Peru) is characterised by two mortuary phases. Based on associated grave finds and the lack of habitation sites near the cemetery, it has been hypothesised that both burial populations came from a certain distance of the site (ca. 20 km) and that they relied on land rather than marine resources. We tested these hypotheses, based on material culture, through stable isotope analysis. The aim was to understand the populations’ diet and geographic origins. We sampled 47 human individuals and eleven sets of faunal remains from both phases for stable isotope analysis (carbon, nitrogen, sulphur and oxygen) of bone and dental collagen, and apatite. Modern samples of autochthonous food were also tested as a baseline for comparison. The results showed preservation differences between the remains from both phases. Individuals from Phase 1 provided the best isotopic dataset and showed consumption of protein from marine resources and C4 plants. On the other hand, bioapatite carbon and oxygen stable isotope results from both phases highlighted differences in C4 plant consumption and individuals of possible non-local origin. The results underline the need to study further the effect of brewed or cooked beverages on bioapatite oxygen levels. Finally, results from Phase 1 fit with the broader dietary pattern evident in other Andean sites, where coastal populations consumed marine protein and C4 plants, as opposed to highland populations who relied on terrestrial protein sources and C3 plants

Shifts in species richness, herbivore specialization, and plant resistance along elevation gradients.

Environmental gradients have been postulated to generate patterns of diversity and diet specialization, in which more stable environments, such as tropical regions, should promote higher diversity and specialization. Using field sampling and phylogenetic analyses of butterfly fauna over an entire alpine region, we show that butterfly specialization (measured as the mean phylogenetic distance between utilized host plants) decreases at higher elevations, alongside a decreasing gradient of plant diversity. Consistent with current hypotheses on the relationship between biodiversity and the strength of species interactions, we experimentally show that a higher level of generalization at high elevations is associated with lower levels of plant resistance: across 16 pairs of plant species, low-elevation plants were more resistant vis-à-vis their congeneric alpine relatives. Thus, the links between diversity, herbivore diet specialization, and plant resistance along an elevation gradient suggest a causal relationship analogous to that hypothesized along latitudinal gradients