Introduction

Abstract

Indonesia’s primates are remarkable in their rich diversity and number of taxa. Indonesia belongs to the Sundaland Biodiversity hotspot in terms of both flora and mammal species (Supriatna et al. 2001), and this collection of over 17,000 islands may be home to the most diverse collection of primates in the world. Conservation is an important issue to consider for all primates, but the Indonesian primates are especially at risk. According to the IUCN/SSC Primate Specialist Group (IUCN/SCC 2008), over 70% of Asian primate species are threatened by extinction, and 84% of the over 40 Indonesian primate species are threatened. A report compiled by Primate Specialist Group of IUCN’s Species Survival Commission (SSC), the International Primatological Society (IPS), and Conservation International (CI), identifies three of the world’s twenty-five most endangered primates as species endemic to Indonesia, including the Siau Island tarsier (Tarsius tumpara), the pig-tailed langur (Simia concolor), and the Sumatran orangutan (Pongo abelii) (Mittermeier et al. 2007). Nearly half of the Indonesian primate species are endemic, a percentage second only to one country, Madagascar. This high proportion of endemic primates makes Indonesia a particularly significant place to study the evolution of variation in primate taxa.