Fig 1.
Map of the Maros-Pangkep study area.
A, Sulawesi in its regional context. It is the largest landmass in Wallacea, the zone of biofaunally unique oceanic islands located between the continental regions of Sunda and Sahul. The two main conjectured dispersal pathways taken by modern humans to get from Sunda to Sahul are represented by red (northern route) and purple (southern route) arrows. The southwestern peninsula of Sulawesi (area within the rectangle) is shown in the inset panel (B). B, South Sulawesi, showing the location of the Maros-Pangkep limestone karst area and sites mentioned in the paper: 1) Leang Bulu Bettue; 2) Leang Burung 2; 3) Leang Sakapao 1; 4) Leang Timpuseng; 5) Ulu Leang 1; 6) Leang Karampuang; 7) Leang Tedongnge; 8) Leang Bulu’ Sipong 4. The Walanae Depression is situated between two major faults and bounded to the north by Lake Tempe. Plio-Pleistocene fossil deposits occur on either side of the Walanae River. Basemap adapted from GEBCO [3] available for public use, DENMAS 2025 CC BY_NC 4.0 (https://tanahair.indonesia.go.id/demnas/#/demnas), and reference [4].
Fig 2.
Leang Bulu Bettue in the Maros-Pangkep karst area of South Sulawesi.
A, Location of the site (and Leang Samalea at the opposite side of the karst tower); B, Leang Bulu Bettue cave and rock-shelter complex; C, View of cave mouth and adjoining rock-shelter from inside the interior chamber; D, Overview of the Shelter Trench (2023), facing north towards the entrance to the interior cave chamber.
Fig 3.
A-B, 3D rendering of the cave passage through the limestone karst tower showing Leang Bulu Bettue and Leang Samalea at either end (detail of the area inside the red rectangle is shown in B). The location of the Cave Mouth Trench and Shelter Trench is shown in B; C-D, Plan view of Leang Bulu Bettue showing the distribution of the excavation squares (Cave Mouth Trench and Shelter Trench).
Fig 4.
3D schematic diagram of the Leang Bulu Bettue chronostratigraphic sequence.
A, Stratigraphy revealed by the Cave Mouth Trench; B, deepest stone artefact (unifacial ‘pick’, layer 10a at 5 m depth) (a 3D model of this artefact is available at: https://une.pedestal3d.com/r/SPiaqbVMjw). Ka = thousand years ago.
Fig 5.
Stratigraphy at Leang Bulu Bettue.
A, upper stratigraphy to a depth of ~4 m below surface (2014 excavations). The main profile shown is the south wall of squares -A1 and -A2; B, west wall of square -A2 (2014 excavations). The distinctive thinly stratified yellowish-orange strata are layers 3a-f (cemented flowstone intercalated with silt). This ~1 m-thick unit lies directly atop the first Late Pleistocene deposit, layer 4a; C, north wall of square -C2 (2015 excavations); D, south wall of square -H2 (during 2015 excavations).
Fig 6.
Stratigraphy at Leang Bulu Bettue.
Depicted here is a composite stratigraphic section exposed in the west walls of the Cave Mouth Trench in the north and the Shelter Trench in the south.
Fig 7.
Typical Phase II faunal remains and lithic artefacts from Leang Bulu Bettue.
A, radial core, square -G2, layer L4c/5 (scale bar 50 mm); B-D, chert bipolar artefacts (scale bars 10 mm); B, -I1, layer 4a, C, -H1 layer 4a, D, layer 4a; E, anvil made on volcanic rock (scale bar 50 mm); F, conjoining flakes from A1 and A2, layer 4, semi-desilicated (scale bar 10 mm); G, chert redirecting flake with a second embedded bulb of percussion, layer 4b (scale bar 10 mm); H, maxillary and mandibular elements attributed to Sus celebensis (Sulawesi warty pig); I, layer 4a (scale bar 30 mm); J and K, layer 4a (scale bars 10 mm); L, layer 4a (scale bar 20 mm); L-N, maxillary and mandibular elements, Ailurops ursinus (bear cuscus) (scale bars 10 mm); L, layer 4b, M and N, layer 4a; O-Q, A. ursinus postcranial elements; O and P, layer 4b (scale bar 10 mm), Q, layer 4a (scale bar 10 mm).
Fig 8.
Chert blade-like flakes from the Phase II occupation.
A, broken blade-like flake with ochre residue on dorsal ridge; B and D, layer 4b; C, E, G, and H, layer 4b; F, layer 4/5; I, layer 4c; J, single-platform blade-like core, layer 4a. All scale bars 10 mm. See also [57] for more information on the lithic technologies at LBB.
Fig 9.
Finds related to the processing and use of mineral pigment (Phase II).
A, utilised ochre nodule (layer 4a); on the accompanying illustration, striations from scraping are depicted in dark grey; B, ochre flake with flake scars at the proximal extremity suggesting it was detached from a larger nodule (layer 4b). A central (dorsal) facet reaches 14.8 mm from the distal edge, and, along with a single facet located on both the left and right sides of this central one, displays evidence for abrasion (note: white residue visible in these images is a fungus that developed post-excavation); C, ochre plaquette (layer 4b). A single incised line 7.14 mm long was observed on one side. Also observed on the same side of the incision is a lightly scraped section done with a stone tool-edge; D, use-worn ochre piece (layer 4a); light grey = ground area; dark grey = scraped area; E, use-worn ochre piece (layer 4a); light grey = ground area; dark grey = scraped area; mid grey = scraped area partial worn away by abrasion; F, chert artefact with ochre residues (layer 4f); G, chert artefact with ochre residues (layer 4f). All scale bars 10 mm).
Fig 10.
Symbolic material culture items from Leang Bulu Bettue.
The artefacts were all recovered from Phase II occupation deposits. A-E, Stone artefacts with incised lines on remnant cortex patches (vertical white scale bar is 10 mm); F, flowstone slab with painted black line; the photograph of the specimen has been enhanced using a DStretch filter (YDT) to better show the pigment (horizontal white scale bar is 50 mm); G, suid tooth root with refitting bead blank(scale bar 5 mm). H, bear cuscus (Ailurops ursinus) phalanx with perforation for use as ornament. H1 provides detail of the intact perforation (scale bar 1 mm). I, engraved piece of limestone from layer 4a.
Fig 11.
Lower stratigraphy at Leang Bulu Bettue (Cave Mouth Trench).
A, northern and western walls of the 2014 trench (square B2), showing layers 2 to 6; B, southern wall of the 2014 trench (squares -A1 and -A2), showing layers 6a-c and 7-8; C-D, layers 8 to 10a-e (2015 excavations); E, layers 11-12 (2015 excavations).
Fig 12.
Stratigraphic sequence exposed in the Shelter Trench (South Wall).
Looking from north to south.
Fig 13.
Lower stratigraphy in Shelter Trench.
A, Eastern wall of squares -G1/1, -H1/1, and -I1/1; B, southern wall of the lower part of square -I1; C, upper part of the southern wall of squares -I1 and -I1/1.
Fig 14.
Stratigraphic sequence at Leang Bulu Bettue.
This illustration shows the lower stratigraphy exposed by excavations in the Shelter Trench.
Fig 15.
Distribution of finds at Leang Bulu Bettue.
3D-plotted positions of individual archaeological findings (stone artefacts, faunal remains, including shell, and other types) colour-coded according to the three major occupation phases in the main excavations: Phase IV (Austronesian-Neolithic), Phase II (~40 ka to 16 ka) and Phase I (>~40 ka).
Fig 16.
Laser ablation U-series dated faunal remains, Leang Bulu Bettue.
Inset panels next to the faunal samples show close-up images of the laser spot profiles for each sample, annotated accordingly. A, Sample LBB-3 (layer 4a), suid molar embedded in mandible fragment; B, Sample LBB-7 (layer 5), anoa molar fragment; C, Sample LBB-10 (layer 8), anoa molar; G, Sample LBB-13 (layer 10), anoa molar; E, Sample LBB-15 (interface between layers 4b and 5), anoa molar; F, Sample LBB-17 (layer 11), anoa molar; G, Sample LBB-19 (layer 8), anoa metacarpus sinistral; H, Sample LBB-18 (layer 10d), Elephantidae lamel fragment. All scale bars are 10 mm in length.
Fig 17.
Laser ablation U-series dated faunal remains, Leang Bulu Bettue.
Inset panels next to the faunal samples show close-up images of the laser spot profiles for each sample, annotated accordingly. A, Sample 3617−1 and 3617−2 (layer 4b), suid molar embedded in mandible; B, Sample 3610 (layer 4b), suid molar; C, Sample 3612 (layer 4f), bovid molar; D, Sample 3614 (layer 5), bovid molar; E, Sample 3613 (layer 5), bovid incisor; F, Sample 3609 (layer 5), bovid incisor; G, Sample 3611 (layer 8), bovid molar; H, Sample 3608A/B (layer 8), possible Palaeoloxodon cf. namadicus molar in mandibular ramus; I, Sample 3615 (layer 8), bovid molar; J, Sample 3616 (layer 10a), bovid molar in mandible fragment. All scale bars are 10 mm in length, with the exception of that in J, which is 50 mm in length.
Fig 18.
Distribution, frequency, and characteristics of faunal remains at Leang Bulu Bettue.
Left panel: black triangles indicate the total number of vertebrate specimens per 10-cm-deep excavation spit (including fossil fragments obtained from wet-sieving, but excluding fish teeth); blue diamonds indicate the amount of small-bodied vertebrate remains as a percentage of the total number of finds per spit (maximum 100%, including unidentifiable and identifiable bone fragments of Phalangeridae, primates, viverrids, birds, and reptiles); red diamonds indicate the amount of large-bodied vertebrate remains as a percentage of the total number of finds per spit (maximum 100%, including unidentifiable and identifiable bone fragments of Suinae, bovine, and proboscideans). Note the different scale for the upper part (layers 1-5) and lower part (layers 6a-13) of the panel. Central panel: vertical range chart of key taxa based on diagnostic faunal remains. Black crosses indicate the presence of a taxon in a particular spit of Quadrant -A1. Some ranges could be extended with identifiable remains from other quadrants. These are indicated with crosses of other colours (key in upper right corner). Right panel: black diamonds indicate the number of bone fragments with signs of heating/burning; blue diamonds indicate the amount of specimens with signs of water transport (rounding, water-rolled) as a percentage of the total amount of finds per spit.
Fig 19.
Bovid fauna from Leang Bulu Bettue (Cave Mouth Trench).
A, Partial cranium of a small-sized anoa, probably mountain anoa (Bubalus quarlesi) (layer 10d; scale = 100 mm); B, anoa incisor (layer 5; scale = 10 mm); C, anoa mandible (layer 10b; scale = 50 mm); D, anoa mandible (layer 10c; scale = 50 mm); E-F, metapodials from lowland anoa (B. depressicornis) (E) and B. quarlesi (F); both specimens are from layer 10a (scale bars in E and F are 50 mm in length). G, babirusa left upper canine (layer 5). Scale = 10 mm.
Fig 20.
Proboscidean fauna from Leang Bulu Bettue.
A, Partial metatarsal of an unidentified elephant from layer 5 (scale = 10 mm); B, Stegodon sp. molar fragment from the layer 10 fluvial sequence (scale = 10 mm); C, partial right mandibular ramus from a young adult elephant provisionally assigned to Palaeoloxodon cf. namadicus (layer 8; scale = 100 mm); D, isolated left lower molar from the previous individual (C) (layer 8; scale = 50 mm); E, juvenile elephant mandible from layer 10d (scale = 10 mm), with two isolated molar fragments from the same mandible illustrated alongside (E1-2).
Fig 21.
Characteristic finds from the deep deposits in the Shelter Trench.
A, anoa frontal with horn cores (square -H1/1, spit 43, layer ST6b2); B, anoa metapodials (left: square -I1/1, spit 45, layer ST7; right: square -H1, spit 42, layer ST6b3/7); C, Suidae humerus (square -I1/1, spit 46, layer ST8); D, isolated proboscidean molar lamel, provisionally attributed to Palaeoloxodon cf. namadicus (square -I1/1, spit 31, layer ST6); E, proboscidean tusk fragments (square -I1/1, spit 47, layer ST8); F, possible Celebochoerus sp. tusk fragment (square -G1/1, spit 33, layer ST10); G-H, desilicated chert artefacts from slot trench; G radial core (square -I1/1, spit 33, layer ST6b3) and H retouched flake with ‘perforator’-like morphology (square -C1/1, spit 40, layer ST8, 410-420 cm below datum). Scale bars 20 mm.
Fig 22.
Proboscidean faunal element and stone artefact in close proximity in layer 8 (Cave Mouth Trench).
The blue arrow indicates the stone artefact, a unifacially flaked ‘pick’ (see Fig 25A). The white arrow points to an associated right mandibular corpus of a proboscidean, possibly Palaeoloxodon cf. namadicus.
Fig 23.
Faunal remains with signs of butchery.
A-D, layer 13; E, layer 8; F, layer 10e. A, macaque left acetabulum (square -A2, layer 13, spit 77) with multiple cut marks. The proximal edges of the cut mark show raised shoulders (1) indicative of slicing. Initiation is identifiable due to a secondary groove running oblique to the main groove (2). Transverse microstriations (3) run oblique and perpendicular across the mark. The black scale bar in the micrograph is 1000 µm. The white scale bar in the right-hand image is 10 mm in length; B, unidentified bone fragment (square A2, layer 13, spit 77) bearing multiple cut-marks with patches of parallel micro-striations. The cut mark (1) is intruded into by natural striations (2) that are likely post-depositional in origin. The black scale bar in the micrograph is 1000 µm. The white scale bar in the right-hand image is 10 mm in length; C, bovid rib fragment (square A2, layer 13, spit 79) with a deep V-shaped stria. The cut mark comprises a deep, relatively straight stria that starts with a barb and terminates in a large, wide groove (1). The shoulder at the termination is exfoliated (2). The shape of the groove is V-shaped, where one wall is straight and the other flares out on an angle, making the mark appear wider (3). The black scale bar in the micrograph is 1000 µm. The white scale bar in the bottom image is 20 mm in length; D, unidentified long bone fragment (probably Macaca sp. radius) (square A2, layer 13, spit 78) with parallel cutmarks underlying multiple fractures. The specimen bears two symmetrical, V-shaped grooves with microstriations along the walls and bottom of the interior (1). There are several fracture lines, as well as pitting and staining, that run transversely across both of the modifications (2), which denotes that the modifications were the primary event. The black scale bar in the micrograph is 1000 µm. The white scale bar in the right-hand image is 10 mm in length; E, anoa humerus with cutmarks inside a tuberosity, indicating intentional removal of muscle attachments. Several striae inside a large depression at the distal end of the humerus are evident (1). Several marks initiate parallel to the long-axis of the bone running proximal-distal before changing direction to run oblique to the long-axis (2, 3). The black scale bar in the micrograph is 1000 µm. The white scale bar in the right-hand image is 10 mm in length; F, anoa tibia showing five deep, parallel V-shaped striae running perpendicular to the long axis of the bone on the lateral margin of the right distal tibia. The large stria has markers that are consistent with movement of the wrist during butchery (1). The four distal striae are wide and slightly asymmetrical in morphology with a curved trajectory. The striae also have a strong shoulder, indicative of a sharp tool cutting into the bone at an angle (2). There is also evidence of long, thin fractures running over the top of the group indicating that the marks are older than the fractures (3). Black scale bars in the micrographs are 1000 µm. The white scale bar in the bottom image is 20 mm in length.
Fig 24.
Lower Industry stone artefacts from LBB.
A, Retouched volcanic flake, layer 5 (scale = 10 mm); B, unifacially retouched volcanic pick, layer 5; C, bifacially retouched volcanic cobble, layer 5 (scale = 10 mm) (a 3D model of this artefact is available at: https://une.pedestal3d.com/r/NnRSE6oPqd); D, retouched chert flake, layer 8 (scale = 10 mm); E, unifacially retouched limestone pick (layer 5), with diacritical illustration (F) (scale = 50 mm); G, unifacially retouched volcanic pick (layer 10a), with diacritical illustration (H) (scale = 50 mm) (a 3D model of this artefact is available at: https://une.pedestal3d.com/r/SPiaqbVMjw).
Fig 25.
Picks and pick-like core tools from the Lower Industry at Leang Bulu Bettue.
All three specimens were made on volcanic cobbles. A, layer 8; B, layer 8; C, layer 5. The pick in A was found adjacent to the right mandibular corpus of a proboscidean, possibly Palaeoloxodon cf. namadicus (see Fig 21). Scale bars 50 mm.
Fig 26.
Limestone cores from the deep deposit in the Shelter Trench.
A is from layer ST6b, B layer 4c/5, and C layer ST7. Scale bars = 20 mm.