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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