Introduction
Deforestation, particularly in the tropics, is precipitating an extinction crisis (Bradshaw et al. 2009). Humandriven habitat loss has increased the species extinction rate by two to three orders of magnitude compared with background rates of extinction deduced from the fossil
record (Pimm et al. 1995; Dirzo & Raven 2003). Empirical evidence for recent extinctions due to land-use can either be obtained by comparing past and present species lists from areas that have undergone land-cover changes (i.e., historical studies; e.g., Robinson 1999; Castelletta et al. 2000; Sodhi et al. 2005, 2006b) or by comparing disturbed (e.g., fragmented) and nearby contiguous habitats (Karr 1982; Newmark 1991; Renjifo 1999). Historical studies provide the best direct evidence of local extinctions,but they are limited to locations where species inventories were conducted in the past. Furthermore,historical studies that documented species extinctions
usually focused on a single site; therefore, their results may not be applicable to other areas. Current-day comparisons of species in fragmented versus intact ecosystems are subject to the criticism that “missing” species may not have occurred in the sites, even before disturbance
(Sodhi et al. 2004b). Overall, evidence for deforestationmediated extinctions remains poor.
Introduction
Deforestation, particularly in the tropics, is precipitating an extinction crisis (Bradshaw et al. 2009). Humandriven habitat loss has increased the species extinction rate by two to three orders of magnitude compared with background rates of extinction deduced from the fossil
record (Pimm et al. 1995; Dirzo & Raven 2003). Empirical evidence for recent extinctions due to land-use can either be obtained by comparing past and present species lists from areas that have undergone land-cover changes (i.e., historical studies; e.g., Robinson 1999; Castelletta et al. 2000; Sodhi et al. 2005, 2006b) or by comparing disturbed (e.g., fragmented) and nearby contiguous habitats (Karr 1982; Newmark 1991; Renjifo 1999). Historical studies provide the best direct evidence of local extinctions,but they are limited to locations where species inventories were conducted in the past. Furthermore,historical studies that documented species extinctions
usually focused on a single site; therefore, their results may not be applicable to other areas. Current-day comparisons of species in fragmented versus intact ecosystems are subject to the criticism that “missing” species may not have occurred in the sites, even before disturbance
(Sodhi et al. 2004b). Overall, evidence for deforestationmediated extinctions remains poor.
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