• Macaca;
  • speciation;
  • socioecology;
  • behavior;
  • human-macaque interface;
  • conservation


The oceanic island of Sulawesi, Indonesia, has long been of interest to scholars, including one of the leading evolutionary thinkers of the nineteenth century: Alfred Russell Wallace. During his explorations of the Malay archipelago, Wallace1 was particularly struck with the ecology of Sulawesi (formally Celebes), noting the depauperate, yet distinctive nature of its fauna. It was home to members of both Asian and Australian faunas. Today, the asymmetrical four-armed island of Sulawesi is regarded as the center of Wallacea, a unique biogeographical zone where endemism levels are incredibly high.2 Of the 127 mammals indigenous to Indonesia, 79 (62%) are endemic to Sulawesi. Among these are seven species of the genus Macaca,3 the most geographically widespread and ecologically diverse of nonhuman primate genera. In this paper, I trace the history and development of the major research trends on these endemic primates over the last four decades since Fooden's3 landmark 1969 publication. These research trends include origin, speciation, and taxonomy; socioecology and behavior; ecology and conservation; and, most recently, the human-macaque interface.