Environmental change, extinction and human activity: evidence from caves in NW Madagascar

In the last 2000 years, changes on the island of Madagascar have resulted in the modification of key environments and the extinction of nearly all large native animals. Humans have long been suspected as the primary cause of this ecological catastrophe, but the exact mechanisms of the island's rapid transformation and the role of natural factors such as climate change remain uncertain. Caves in northwestern Madagascar are helping researchers to disentangle these factors, by providing many types of datable information concerning the past in close physical proximity. U-series dated pollen spectra from the caverns of Anjohibe provide a 40,000-year record of vegetation in the vicinity. Bone deposits from caves in the region provide new site records for extinct tare, including Babakotia radofilai Godfrey et al. 1990, Plesiorycteropus madagascariensis Filhol 1895, and Mullerornis sp. Several extant taxa that were present in the region in the late Holocene are now locally extinct. Archaeological evidence from the caves suggests little or no human activity in the vicinity or interaction with the fauna at these sites until recent centuries.