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New excavations in Liang Bua, where the remains of the ‘Hobbit’ ( Homo floresiensis ) were discovered, show that this diminutive human species used this cave between 190,000 and 50,000 years ago, and not until as recently as 12,000 years ago as previously interpreted; modern humans have been present in Australia since around 50,000 years ago, so whether Homo floresiensis survived long enough to witness the arrival of modern humans is still an open question. An earlier date for Homo floresiensis The discovery in Liang Bua cave on the island of Flores in Indonesia of the diminutive Homo floresiensis , an archaic member of the human family commonly known as the 'Hobbit', was an archaeological sensation in 2004. A source of considerable debate was the fact that it lived in Liang Bua cave between 95,000 and 12,000 years ago, after modern humans had colonized the area (around 50,000 years ago). Thomas Sutikna and colleagues — including many of the original research team — have gone back to Liang Bua, where new excavations have exposed previously unexplored parts of the cave. They have found that the layers of sediment in the cave are not deposited evenly, and it now seems that the H. floresiensis -bearing strata are older than was thought. New radiometric dating places the H. floresiensis remains and stone artefacts to between 190,000 and 50,000 years ago. Whether H. floresiensis survived long enough to witness the arrival of modern humans is an open question. Homo floresiensis , a primitive hominin species discovered in Late Pleistocene sediments at Liang Bua (Flores, Indonesia) 1 , 2 , 3 , has generated wide interest and scientific debate. A major reason this taxon is controversial is because the H. floresiensis -bearing deposits, which include associated stone artefacts 2 , 3 , 4 and remains of other extinct endemic fauna 5 , 6 , were dated to between about 95 and 12 thousand calendar years (kyr) ago 2 , 3 , 7 . These ages suggested that H. floresiensis survived until long after modern humans reached Australia by ~50 kyr ago 8 , 9 , 10 . Here we report new stratigraphic and chronological evidence from Liang Bua that does not support the ages inferred previously for the H. floresiensis holotype (LB1), ~18 thousand calibrated radiocarbon years before present (kyr cal. bp ), or the time of last appearance of this species (about 17 or 13–11 kyr cal. bp ) 1 , 2 , 3 , 7 , 11 . Instead, the skeletal remains of H. floresiensis and the deposits containing them are dated to between about 100 and 60 kyr ago, whereas stone artefacts attributable to this species range from about 190 to 50 kyr in age. Whether H. floresiensis survived after 50 kyr ago—potentially encountering modern humans on Flores or other hominins dispersing through southeast Asia, such as Denisovans 12 , 13 —is an open question.

Multiple, independent time markers are essential to correlate sediment and ice cores from the terrestrial, marine and glacial realms. These records constrain global paleoclimate reconstructions and inform future climate change scenarios. In the Northern Hemisphere, sub-visible layers of volcanic ash (cryptotephra) are valuable time markers due to their widespread dispersal and unique geochemical fingerprints. However, cryptotephra are not as widely identified in the Southern Hemisphere, leaving a gap in the climate record, particularly during the Last Glacial Maximum (LGM). Here we report the first identification of New Zealand volcanic ash in Antarctic ice. The Oruanui supereruption from Taupo volcano (25,580  ±  258 cal. a BP) provides a key time marker for the LGM in the New Zealand sector of the SW Pacific. This finding provides a high-precision chronological link to mid-latitude terrestrial and marine sites, and sheds light on the long-distance transport of tephra in the Southern Hemisphere. As occurred after identification of the Alaskan White River Ash in northern Europe, recognition of ash from the Oruanui eruption in Antarctica dramatically increases the reach and value of tephrochronology, providing links among climate records in widely different geographic areas and depositional environments.

Stratigraphic, chronological, environmental and faunal context are provided to the newly discovered fossils of hominins that lived in the So’a Basin in Flores, Indonesia, 700,000 years ago; the stone tools recovered with the fossils are similar to those associated with the much younger Homo floresiensis from Flores, discovered in Liang Bua to the west. Second site for Homo floresiensis Until recently, remains of the diminutive Homo floresiensis had been found at a single locality only — in Liang Bua cave on the island of Flores in Indonesia. A pair of papers published in this issue introduces new fossil findings from a second site on Flores, at Mata Menge, to the east of Liang Bua. Gerrit van den Bergh et al . describe a mandible fragment and isolated teeth from several individuals. The remains are as small as, or smaller than, those from Liang Bua, but, at 700,000 years old, are much older. Their morphology supports derivation from Asian Homo erectus . Adam Brumm et al . present the stratigraphic, chronological, environmental and faunal context of the Mata Menge site. The hominins lived some 700,000 years ago in what was then hot, dry savannah grassland, though with a strong wetland component. Stone tools found with the fossils are simple and very like those associated with the much younger Liang Bua H. floresiensis . 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 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 .

We present a geomorphic map of the glacial landforms associated with the Golfo Corcovado ice lobe in northwestern Patagonia. Built upon prior studies, our map elaborates on the central and southern sectors of Isla Grande de Chiloé and neighboring islands. Through a combination of remote sensing techniques and exhaustive fieldwork, we identified a suite of ice-marginal, subglacial, and glaciofluvial features created by the Golfo Corcovado ice lobe during four maxima within the last glacial cycle, in none of which the ice-front reached the Pacific coast of Isla Grande de Chiloé. Our mapping builds a foundation and provides insights for future interdisciplinary research on the Late Quaternary sequence of glacial and paleoclimatic events in this key sector of northwestern Patagonia.

We examined the radiocarbon (14C) reservoir effect in Lake Kutubu using tephrochronology and terrestrial plant material to deliver a precise age-depth profile and sedimentation rates for this lake. Based on the presence of two tephra horizons (Tibito and Olgaboli), we found a reservoir age offset in sediments of between 1490 and 2280 14C yr using the sediment ages derived from the lead-210 (210Pb) dating method. The live submerged biological samples collected exhibited a higher reservoir age offset than the sediment. This is most likely a result of delayed transport of “bomb” 14C from the atmosphere to aquatic and sedimentary system. The 14C reservoir effect increased with distance from the lake inlet and also decreased with depth. Dissolution of 14C-depleted carbon from surrounding limestone and direct in-wash of old soil or vegetation remnants from the catchment are the most likely causes of the 14C reservoir effect. Based on limestone areas mapped in Papua New Guinea, we indicate lakes which may be subject to a significant 14C reservoir effect. The results of this study demonstrate the magnitude of the 14C reservoir effect in lakes and provide insights to the correct interpretation of past environmental and archaeological events in PNG.

Ambae Island is the largest of Vanuatu's active volcanoes. It is also one of the nation's potentially most dangerous, with 60 million m^sup 3^ of lake-water perched at over 1340 m in the summit caldera and over the active vent. In 1995, small phreatic explosions, earthquake swarms and heightened gas release led to calls for evacuation preparation and community volcanic hazard awareness programs for the ~9500 inhabitants. Differences in perspective or world-view between the island dwellers adhering to traditional beliefs (Kastom) and external scientists and emergency managers led to a climate of distrust following this crisis. In an attempt to address these issues, rebuild dialogue and respect between communities, outside scientists and administrators, and move forward in volcanic hazard education and planning for Ambae, we adapted and applied Participatory Rural Appraisal (PRA) approaches. Initial gender-segregated PRA exercises from two representative communities provided a mechanism for cataloguing local traditional viewpoints and hazard perceptions. Ultimately, by combining elements of these viewpoints and perceptions with science-based management structures, we derived volcanic hazard management guidelines, supported by an alert system and map that were more readily accepted by the test communities than the earlier \"top-down\" plans imposed by outside governmental and scientific agencies. The strength of PRA approaches is that they permit scientists to understand important local perspective issues, including visualisations of volcanic hazards, weaknesses in internal and external communication systems, and gender and hierarchy conflicts, all of which can hinder community emergency management. The approach we describe has much to offer both developing and industrialised communities that wish to improve their awareness programs and mitigative planning. This approach should also enhance communication and understanding between volcanologists and the communities they serve.[PUBLICATION ABSTRACT]

A large number of distal, silicic tephra beds have been preserved in the late Cenozoic deposits of the Klondike region, Yukon Territory. Forty-one tephra samples, representing twelve distinctive beds, are detailed in this study. They range in composition from basaltic andesite to high-silica rhyolite, and were deposited during the late Pliocene to Late Wisconsinan time interval. Seven tephra beds are derived from volcanoes in the Wrangell volcanic field, and four come from the more distant eastern Aleutian arc-Alaska Peninsula region, but the source of the single andesitic tephra is unknown. The widespread and well known Old Crow and Sheep Creek tephra beds have been identified in the Klondike district, but all the other tephra units are characterized in detail for the first time. The ages of most tephra beds are poorly constrained, but will undoubtedly become better known with the application of recently developed glass fission-track methods. Hence, prospects are favourable for the eventual development of a comprehensive and reliable time-stratigraphic framework that will support on-going studies on the late Cenozoic geology, geomorphology, paleontology, and paleoenvironments of the Klondike area.