Integrated Analysis of Fossil Lemur Sites

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A newly developed approach to excavation below the water table, tested successfully last year under a High Risk Anthropological Research award, will be applied to fossil lemur sites throughout Madagascar. The anticipated rich yield of data will permit the examination of the nature and timing of the extinctions of the larger native animals and the landscape changes that occurred on the island in the last two thousand years. In the past, sites containing a fossil record of the period during which the extinctions occurred have generally been excavated without suitable stratigraphic control. By creating a temporary depression in the water table in order to remove the sediments with full three-dimensional stratigraphic control, high-pressure ultralight water pumps now make it possible to re-excavate key sites, and open others previously uninvestigated because of their flooded nature. Improvements in radiocarbon dating techniques and a multidisciplinary approach to analysis now make it feasible to correlate evidence from the bones of extinct giant lemurs and other extinct animals with many other types of data, including small vertebrate and invertebrate remains, pollen and plant macrofossils, charcoal particles, stable isotopes, ancient DNA, and human artifacts. Integrating these results at the landscape level, through the choice of key sites from the various regions of the island for detailed analysis and the compilation and evaluation of existing data sets for comparison, will provide the most rigorous test yet devised for the Blitzkrieg Hypothesis (rapid overkill by humans) and five competing hypotheses for the extinctions in Madagascar. Determining the length of the period of overlap between humans and the extinct megafauna and the sequence of biotic changes will be particularly critical to the evaluation of competing explanations for the extinctions. In addition, new insights will be gathered concerning the diet and habits of extinct giant lemurs, range shifts of extant lemur species, and the timing of human arrival and landscape transformation. Applying these techniques will enrich our basic understanding of lemur evolution and ecology and of the role of humans in transforming Madagascar. The Office of International Science and Engineering and Environmental Social and Behavioral Sciences Activities are assisting in the funding in order to enhance international cooperation and educational opportunities for undergraduate students.