Indonesia’s threatened birds: over 500 million years of evolutionary heritage at risk INTRODUCTION When a species becomes extinct, the evolutionary history it embodied is lost with it (Nee & May, 1997). The more distantly related a species is to its nearest relatives, the more history is lost. If one important metric of conservation value is evolutionary distinctness (Wilson, 1992), then measuring the loss of evolutionary history (also called phylogenetic diversity or PD) through anthropogenic-mediated extinction is an important component of conservation biology (Faith, 1992; Crozier, 1997; see also Morowitz, 1991). Theoretical work (Vane-Wright, Humphries & Williams, 1991; Nee & May, 1997; see also Vazquez & Gittleman, 1998; Heard & Mooers, 2000) has quantified the expected pattern of evolutionary loss, and several groups have projected the worldwide amount of loss we might expect under reasonable scenarios of extinction for several taxonomic groups (McKinney, 1998; Russell et al., 1998; Purvis et al., 2000; Von Euler, 2001, Sechrest et al., 2002). However, conservation decisions are normally made at much smaller scales, and here we present the first analysis of projected loss of evolutionary history at the scale of a geopolitical unit, using the birds of Indonesia as a test case. Two-thirds of the world’s bird species are threatened by habitat loss and degradation (Beissinger, 2000) and deforestation is the major threat in Indonesia; at current rates, most of Indonesia’s species- rich lowland forests will have disappeared completely by the year 2010 (Jepson et al., 2001). Using published IUCN red-lists for the threatened bird species of Indonesia (Stattersfield & Capper, 2000), we investigate whether a significantly higher proportion of Indonesia’s, and the world’s (through the loss of endemics) evolutionary history is at risk than if extinction risk were random with respect to taxonomic position (Von Euler, 2001). The amount of PD a particular country (or other geopolitical unit) stewards might be considered that country’s ‘evolutionary heritage’. METHODS Data collection The Indonesian species list is from Andrew (1992), augmented with data from Stattersfield & Capper (2000), Coates, Bishop & Gardner (1997), MacKinnon & Phillipps (1993) and Beehler, Pratt & Zimmerman (1986). Taxonomy is based on Sibley & Monroe (1990). Conservation status data are from Stattersfield & Capper (2000). Where taxonomy data differed between authors, Stattersfield & Capper (2000) was preferred (e.g. species versus subspecies rank: see ‘speciesnotes’ at www.sfu.ca/~amooers/evolheritage for taxonomic decisions). Breeding and non-breeding species are included in the analysis. We considered Indonesia to include East Timor and Irian Jaya (Papua) and its satellites, but not Sarawak, Sabah or Brunei. Exclusion of these areas did not affect the species list since there are no species endemic to Sarawak, Sabah or Brunei. We classified each species two ways, as follows. (1) endemic status: found only in Indonesia (endemic) versus found in at least one other country (non endemic); A. Ø. Mooers 1 and R. A. Atkins 2 1 Department of Biological Sciences, Simon Fraser University, Burnaby, BC, V5A 1S6, Canada 2 Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, The Netherlands (Received 21 October 2002; accepted 4 December 2002) Abstract Using published IUCN red-lists for the threatened bird species of Indonesia (Stattersfield & Capper, 2000), we document that the species at risk in Indonesia are not a taxonomically random sample, consistent with patterns seen at the global scale (Purvis et al., 2000). This implies that a greater than random proportion of Indonesia’s and the world’s (through the loss of endemics) phylogenetic diversity (PD) is at risk (Von Euler, 2001). Using cytochrome b (Johns & Avise, 1998) and a distance-based taxonomy, we attempt to quantify this projected loss of PD in millions of years and conclude with a brief discussion of the conservation implications for Indonesia, and of the use of ‘evolutionary heritage’ as a measure for conservation at the geopolitical level. All correspondence to: Dr Arne Ø. Mooers. Tel: +1 604–291–3979; Fax: +1 604–291–3496; E-mail: amooers@sfu.ca Animal Conservation (2003) 6, 183–188 © 2003 The Zoological Society of London DOI:10.1017/S1367943003003226 Printed in the United Kingdom