Last appearance of Homo erectus at Ngandong, Java, 117,000-108,000 years ago.

Homo erectus is the founding early hominin species of Island Southeast Asia, and reached Java (Indonesia) more than 1.5 million years ago1,2. Twelve H. erectus calvaria (skull caps) and two tibiae (lower leg bones) were discovered from a bone bed located about 20 m above the Solo River at Ngandong (Central Java) between 1931 and 19333,4, and are of the youngest, most-advanced form of H. erectus5-8. Despite the importance of the Ngandong fossils, the relationship between the fossils, terrace fill and ages have been heavily debated9-14. Here, to resolve the age of the Ngandong evidence, we use Bayesian modelling of 52 radiometric age estimates to establish-to our knowledge-the first robust chronology at regional, valley and local scales. We used uranium-series dating of speleothems to constrain regional landscape evolution; luminescence, 40argon/39argon (40Ar/39Ar) and uranium-series dating to constrain the sequence of terrace evolution; and applied uranium-series and uranium series-electron-spin resonance (US-ESR) dating to non-human fossils to directly date our re-excavation of Ngandong5,15. We show that at least by 500 thousand years ago (ka) the Solo River was diverted into the Kendeng Hills, and that it formed the Solo terrace sequence between 316 and 31 ka and the Ngandong terrace between about 140 and 92 ka. Non-human fossils recovered during the re-excavation of Ngandong date to between 109 and 106 ka (uranium-series minimum)16 and 134 and 118 ka (US-ESR), with modelled ages of 117 to 108 thousand years (kyr) for the H. erectus bone bed, which accumulated during flood conditions3,17. These results negate the extreme ages that have been proposed for the site and solidify Ngandong as the last known occurrence of this long-lived species.

The oldest gibbon fossil (Hylobatidae) from insular Southeast Asia: evidence from Trinil, (East Java, Indonesia), Lower/Middle Pleistocene.

A fossil femur excavated by Eugène Dubois between 1891-1900 in the Lower/Middle Pleistocene bonebed of the Trinil site (Java, Indonesia) was recognised by us as that of a Hylobatidae. The specimen, Trinil 5703 of the Dubois Collection (Leiden, The Netherlands), has the same distinctive form of fossilization that is seen in many of the bonebed fossils from Trinil in the collection. Anatomical comparison of Trinil 5703 to a sample of carnivore and primate femora, supported by morphometric analyses, lead to the attribution of the fossil to gibbon. Trinil 5703 therefore provides the oldest insular record of this clade, one of the oldest known Hylobatidae fossils from Southeast Asia. Because living Hylobatidae only inhabit evergreen rain forests, the paleoenvironment within the river drainage in the greater Trinil area evidently included forests of this kind during the Lower/Middle Pleistocene as revealed here.

Historical evidence of the 1936 Mojokerto skull discovery, East Java.

To resolve ambiguities in the literature, we detail the discovery history of the Mojokerto child's skull (Perning 1), employing letters, maps, photographs, reports, and newspaper accounts not previously used for this purpose. Andoyo, an experienced vertebrate-fossil collector with the Geological Survey of the Netherlands Indies, found the skull on February 13, 1936, while collecting for Johan Duyfjes, who had mapped the field area geologically. On February 18-19 Andoyo sent the fossil and a 1:25,000-topographic map showing the discovery point to Survey headquarters. The locality lies between Perning and Sumbertengu villages, approximately 10km northeast of Mojokerto city, East Java. G.H. Ralph von Koenigswald, Survey paleontologist, identified the specimen as Pithecanthropus and then named it Homo modjokertensis (it is now accepted as Homo erectus). Unfortunately he confused the discovery record in a March 28 newspaper article by characterizing the skull as a "surface find" [Dutch: oppervlaktevondst] while also attributing it to ancient beds. von Koenigswald probably had insufficient basis for either assertion, having not yet talked to Andoyo or Duyfjes. Eugene Dubois challenged von Koenigswald on the "surface-find" issue, Andoyo was consulted, and Duyfjes went to the site. Duyfjes and von Koenigswald then published scientific papers stating that the skull was unearthed 1m deep from a hill-slope outcrop of conglomeratic sandstone in Duyfjes' Pucangan formation. A cross section by Andoyo, which may show the Mojokerto site, also indicates a skull at 1m depth in conglomeratic sandstone. Photographs taken in 1936-1938 show a shallow pit at a single field location that fits Duyfjes' site description and is identified as the Mojokerto-skull site in 1940-1943 publications. By WWII the scientific community accepted the skull as an early hominid. Although von Koenigswald's "surface-find" comment remains a source of doubt in the record, we consider in situ discovery for the Mojokerto skull to be very likely.