1. School of Natural Sciences and Psychology, Liverpool John Moores University, James Parsons Building, Byrom Street, L33AF Liverpool, UK.
2. Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Sciencepark 904, Amsterdam 1098, Netherlands.
3. Sumatran Orangutan Conservation Programme, Jalan Wahid Hasyim 51/74, Medan 20154, Indonesia.
4. Department of Anthropology, Southern Illinois University, 1000 Faner Drive, Carbondale, IL 62901, USA.
5. Fakultas Biologi, Universitas Nasional, Jalan Sawo Manila, Pasar Minggu, Jakarta Selatan 12520, Indonesia.
6. Leuser Conservation Forum, Jalan Geuchik Raja No. 89 A, Banda Aceh 23233, Indonesia.
7. Yayasan Orangutan Sumatera Lestari–Orangutan Information Centre, Jalan Bunga Sedap Malam 18C No. 10, Medan 20131, Indonesia.
8. Center for International Forestry Research, P.O. Box 0113 BOCBD, Bogor 16000, Indonesia.
9. Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany.
10. German Centre for Integrative Biodiversity Research (iDiv), Halle-Jena-Leipzig, Deutscher Platz 6, 04103 Leipzig, Germany.