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Mata Menge is located near the northwestern margin of the So'a Basin, a ~400[km.sup.2] geological depression in central Flores (Fig. 1). The basement substrate consists of the Ola Kile Formation [...], Recent excavations at the early Middle Pleistocene site of Mata Menge in the So'a Basin of central Flores, Indonesia, have yielded hominin fossils (1) attributed to a population ancestral to Late Pleistocene Homo floresiensis (2). 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 [sup.40]Ar/[sup.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.

Analyses of Pleistocene fossil proboscideans have long been used as indirect evidence for climactic and environmental shifts in the Sunda shelf of Southeast Asia. Reconstructing the biological effects of rainforest expansion at the Last Glacial Maximum on elephants can be enhanced by a better understanding of fossil proboscidean palaeobiology. We studied fragmented post-cranial fossil remains of an Asian elephant (Elephas maximus) from Pulau Bangka, an island to the east of Sumatra, hypothesised to be within the Late Pleistocene Sundaland savannah corridor. Bone histology of the humerus, rib, and vertebrae from the Bangka fossil were examined and compared with modern conspecifics to reconstruct remodelling. We measured secondary osteon population density, osteon area, diameter, and infill ratios in Haversian bone. Intra-skeletally, we found that the histology of the largely weight-bearing humerus indicated slower remodelling than that of the ribs and vertebrae, which are less biomechanically constrained. Inter-skeletally, the fossil rib histology showed relatively smaller osteons and Haversian canals when compared to the modern samples. Differences in lifestyles, including range-expansion, may have influenced micro-morphometric differences in elephant rib histology. Our results contribute indirect evidence of the effects of climactic variability in the Sunda palaeoenvironment on Pleistocene fauna. [ABSTRACT FROM AUTHOR]