a, Corridor of dispersal of fauna into southeast Asia during periods of connection (redrawn with permission from ref. 7). b, The main fossil faunal sites in southeast Asia. In southern China: 1, Luijiang; 2, Liucheng; 3, Hoshantung; 4, Hei-Tu’ung; 5, Changyang; 6, Hsing-an. In Vietnam: 7, Lang Trang; 8, Tham Khuyen; 9, Thung Lang; 10, Hang Hum; 11, Ma U ‘Oi; 12, Tham Om; 13, Keo Leng. In Laos: 14, Tham Hang; 15, Tham P’a Loi. In Thailand: 16, Thum Wiman Nakin; 17, Thum Phra Khai Phet. In Cambodia: 18, Phnom Loang. In Borneo; 19, Niah Cave. In Indonesia: 20, Lida Ajer; 21, Sibrambang; 22, Punung (redrawn with permission from ref. 7). c, Dubois’ field sketches of Lida Ajer cave location copied directly from his field notebook—now housed in Leiden (with permission from the Naturalis, the Netherlands). His rough sketch of the cave location close to Payakumbuh village has had annotations added to make the features clearer. d, Our map of the cave location for comparison, note the similar relationship between Mount Sago, River Agam and Lida Ajer. e, Dubois’ plan of the cave, annotations have been added to identify the chambers discussed in the text. f, Our plan of the cave for comparison, with the only differences being the absence of the sinkhole passage on our plan (unmapped).