PALAEOINVA · Palaeoecological Exploration of Human-Linked Biological Invasions on Madagascar

Loss of biodiversity is one of the most urgent ecosystem threats, and this is particularly clear on tropical islands such as Madagascar. Effective conservation efforts should be informed by assessments of synergistic threats from deforestation, biological invasions, and climate change, which operate on multiple timescales. This proposal uses multidisciplinary biochemical analysis of bones from archaeological and paleoecological deposits on Madagascar to identify endemic predators (fosa) and small mammals (mouse lemurs and rodents) that may be vulnerable to deforestation and negative interactions with exotic counterparts (dogs, rats, and mice). Specifically, we will apply bulk stable isotope analysis to exotic and endemic animal bone collagen from the past ~3,000 years to characterize dietary niches and evaluate the potential for different cases of predation and competition. To obtain a deeper understanding of resource use than is possible with prevailing bulk isotope methods, this project will also include the stable isotope analysis of individual amino acids present in bone collagen. Radiocarbon data from the same bones will substantially contribute to our knowledge of past animal translocations in the western Indian Ocean region. We will also start to identify taxon-specific responses to past changes in resource availability by comparing stable isotope datasets from directly 14C-dated bones with regional records of past climate and vegetation change. These project components will pin-point the degree to which competition has exacerbated (or not) the vulnerability of endemic species to human land management and climate change. The research is consistent with both the current research foci of the host institution and the career interests of the applicant, and the results will answer questions important to the historical sciences, modern biodiversity conservation, and rural communities around the study sites.