Recent excavations at the early Middle Pleistocene site of Mata Menge in the So'a Basin of central Flores, Indonesia, have yielded hominin fossils attributed to a population ancestral to Late Pleistocene Homo floresiensis. Here we describe the age and context of the Mata Menge hominin specimens and associated archaeological findings. The fluvial sandstone layer from which the in situ fossils were excavated in 2014 was deposited in a small valley stream around 700 thousand years ago, as indicated by (40)Ar/(39)Ar and fission track dates on stratigraphically bracketing volcanic ash and pyroclastic density current deposits, in combination with coupled uranium-series and electron spin resonance dating of fossil teeth. Palaeoenvironmental data indicate a relatively dry climate in the So'a Basin during the early Middle Pleistocene, while various lines of evidence suggest the hominins inhabited a savannah-like open grassland habitat with a wetland component. The hominin fossils occur alongside the remains of an insular fauna and a simple stone technology that is markedly similar to that associated with Late Pleistocene H. floresiensis.

Sulawesi is the largest and oldest island within Wallacea, a vast zone of oceanic islands separating continental Asia from the Pleistocene landmass of Australia and Papua (Sahul). By one million years ago an unknown hominin lineage had colonized Flores immediately to the south1, and by about 50 thousand years ago, modern humans (Homo sapiens) had crossed to Sahul2, 3. On the basis of position, oceanic currents and biogeographical context, Sulawesi probably played a pivotal part in these dispersals4. Uranium-series dating of speleothem deposits associated with rock art in the limestone karst region of Maros in southwest Sulawesi has revealed that humans were living on the island at least 40 thousand years ago (ref. 5). Here we report new excavations at Talepu in the Walanae Basin northeast of Maros, where in situ stone artefacts associated with fossil remains of megafauna (Bubalus sp., Stegodon and Celebochoerus) have been recovered from stratified deposits that accumulated from before 200 thousand years ago until about 100 thousand years ago. Our findings suggest that Sulawesi, like Flores, was host to a long-established population of archaic hominins, the ancestral origins and taxonomic status of which remain elusive. (Fig. 1) To clarify these issues, we conducted surveys in the Cabenge area between 2007 and 2012, 54 leading to the discovery of four new sites with stone artefacts in situ in stratigraphic context. Disciplines Medicine and Health Sciences | Social and Behavioral Sciences 55At Talepu, one of the four newly-discovered sites, we undertook deep-trench excavations. 56The site is located 3 km southeast of Cabenge and 13 km downstream from the point where 57 the Walanae River leaves its confining valley and enters a widening, actively subsiding 58 floodplain towards the north (Fig. 1, see also Extended Data Fig. 1). During the Pleistocene, Our excavations focused on the northernmost hill of an elongated ridge near Talepu village, 68 some 600 m west of the Walanae River (Fig.1c). The summit of Talepu Hill lies 32 m above and silt layers overlaid by alluvial cobble gravels (Fig. 1c, Extended Data Fig. 2). Two deep 72 excavations were undertaken at Talepu (Trenches T2 and T4) to provide a combined 18.7 m-73 long stratigraphic section in which five main sedimentary units are exposed. In descending 74 order of depth, these are: Units A, B, C, D and E (Fig. 2). 76These excavations have revealed the first evidence of in situ stone artefacts in securely 77 stratified and dated contexts within the Walanae Basin. For instance, the T2 excavation 78 yielded a total of 318 stone artefacts between the surface and 4.9 m depth ( Fig. 3a-i In T4 we recovered 41 stone artefacts from the topsoil and colluvium down to a depth of 90 88 cm. However, three in situ silicified limestone artefacts were found in older strata exposed in 89 T4 (Fig. 3j-m), all within the basal clayey silt of Unit E 2 . These artefacts now provide the 90 stratigraphically earliest evidence for human activity at Talepu. They comprise...

Over 60 years ago, stone tools and remains of megafauna were discovered on the Southeast Asian islands of Flores, Sulawesi and Luzon, and a Middle Pleistocene colonization by Homo erectus was initially proposed to have occurred on these islands. However, until the discovery of Homo floresiensis in 2003, claims of the presence of archaic hominins on Wallacean islands were hypothetical owing to the absence of in situ fossils and/or stone artefacts that were excavated from well-documented stratigraphic contexts, or because secure numerical dating methods of these sites were lacking. As a consequence, these claims were generally treated with scepticism . Here we describe the results of recent excavations at Kalinga in the Cagayan Valley of northern Luzon in the Philippines that have yielded 57 stone tools associated with an almost-complete disarticulated skeleton of Rhinoceros philippinensis, which shows clear signs of butchery, together with other fossil fauna remains attributed to stegodon, Philippine brown deer, freshwater turtle and monitor lizard. All finds originate from a clay-rich bone bed that was dated to between 777 and 631 thousand years ago using electron-spin resonance methods that were applied to tooth enamel and fluvial quartz. This evidence pushes back the proven period of colonization of the Philippines by hundreds of thousands of years, and furthermore suggests that early overseas dispersal in Island South East Asia by premodern hominins took place several times during the Early and Middle Pleistocene stages. The Philippines therefore may have had a central role in southward movements into Wallacea, not only of Pleistocene megafauna , but also of archaic hominins.

west. Our study offers a local framework, but its Pleistocene landscape record has regional significance. Most of all, it forms a much-needed basis for future, detailed studies on the build-up of the hominin site of Trinil, its fossil assemblages and numerical ages.

Three fossil-bearing intervals have been recognized in the Pleistocene So'a Basin, with the upper one holding important evidence of hominin fossils. The sequence also contains numerous in situ stone artifacts and fossils of other vertebrate taxa. Therefore, multiple dating techniques are crucial to secure the age of the fossil and artifactbearing layers, especially the one with the hominin remains. This paper deals with the palaeomagnetic dating of the So'a Basin sequence to assist other dating methods that have been applied, and to refine the chronostratigraphy of the area. Palaeomagnetic sampling was conducted in four sections along a west to east transect. Four magnetozones can be recognized, consisting of two reverse and two normal polarity zones. By using the available radiometric ages as a guide and comparing the So'a Basin magnetostratigraphy with the Standard Geomagnetic Polarity Time Scale (GPTS), it became clear that both reverse magnetozones are part of the Matuyama Chron, while the normal magnetozones are the Jaramillo subchron and the Brunhes Chron. These palaeomagnetic dating results support the available radiometric dates and refine the age of the fossil-bearing deposits of the So'a Basin.