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Catchment modification and increased sediment loads in coastal regions are impacting many of the world's coral reefs, yet relevant water quality data are limited by the availability of instrumental records. Massive Porites spp. corals offer the potential to reconstruct water quality by use of the geochemical proxies that are incorporated into their skeleton. Here we present ∼ monthly resolved rare earth element (REE), yttrium (Y) and barium/calcium (Ba/Ca) concentrations obtained from four Porites corals collected across a known water quality gradient from the Great Barrier Reef, Australia. Sub-annual REE time series patterns were comparable among corals despite having significantly different concentrations. Whilst Ba/Ca did not reflect the known water quality gradient of the region, Y/holmium ratios reflected broad cross shelf water quality gradients and REE concentrations reflected local scale variance in water quality. This study demonstrates that REE analysis of Porites corals offers great potential for assessing changes in water quality in reef environments.

Evidence from the fossil coral record has shown that coral assemblages were able to extend their geographical range to higher latitudes during past global warming events. In the face of future global warming scenarios, we investigate the potential for China's subtropical coral communities to act as a refuge for corals as ocean temperatures continue to warm. Using uranium-thorium dating to chronologically constrain the age of dead corals, we reveal two distinct periods of coral growth between 6.85 and 5.51 ka B.P. and 0.11 to −0.05 ka B.P. (relative to A.D. 1950). The former coincides with the mid-Holocene Warm Period when temperatures in South China were ∼1-2 °C warmer than present. Very few ages (13%) were obtained for the ∼5.6 k.y. that followed. An increased frequency of corals with 230Th ages dated to the past century suggests an increase in abundance coinciding with rising global temperatures. Nevertheless, modern monitoring programs have reported a recent dramatic decline in coral cover over the past 34 yr attributable to human influences. Our results suggest that although coral communities existed around the subtropical islands of Daya Bay (southeast China) in the past, their continued presence in the region largely depends on appropriate management of the adjacent coastline and coupled ocean-atmosphere conditions similar to those experienced in the mid-Holocene.

This paper presents a reassessment of the archaeological record at Leang Burung 2, a key early human occupation site in the Late Pleistocene of Southeast Asia. Excavated originally by Ian Glover in 1975, this limestone rock-shelter in the Maros karsts of Sulawesi, Indonesia, has long held significance in our understanding of early human dispersals into 'Wallacea', the vast zone of oceanic islands between continental Asia and Australia. We present new stratigraphic information and dating evidence from Leang Burung 2 collected during the course of our excavations at this site in 2007 and 2011-13. Our findings suggest that the classic Late Pleistocene modern human occupation sequence identified previously at Leang Burung 2, and proposed to span around 31,000 to 19,000 conventional 14C years BP (~35-24 ka cal BP), may actually represent an amalgam of reworked archaeological materials. Sources for cultural materials of mixed ages comprise breccias from the rear wall of the rock-shelter-remnants of older, eroded deposits dated to 35-23 ka cal BP-and cultural remains of early Holocene antiquity. Below the upper levels affected by the mass loss of Late Pleistocene deposits, our deep-trench excavations uncovered evidence for an earlier hominin presence at the site. These findings include fossils of now-extinct proboscideans and other 'megafauna' in stratified context, as well as a cobble-based stone artifact technology comparable to that produced by late Middle Pleistocene hominins elsewhere on Sulawesi.

Evidence from the fossil coral record has shown that coral assemblages were able to extend their geographical range to higher latitudes during past global warming events. In the face of future global warming scenarios, we investigate the potential for China's subtropical coral communities to act as a refuge for corals as ocean temperatures continue to warm. Using uranium-thorium dating to chronologically constrain the age of dead corals, we reveal two distinct periods of coral growth between 6.85 and 5.51 ka B.P. and 0.11 to −0.05 ka B.P. (relative to A.D. 1950). The former coincides with the mid-Holocene Warm Period when temperatures in South China were ∼1-2 °C warmer than present. Very few ages (13%) were obtained for the ∼5.6 k.y. that followed. An increased frequency of corals with 230Th ages dated to the past century suggests an increase in abundance coinciding with rising global temperatures. Nevertheless, modern monitoring programs have reported a recent dramatic decline in coral cover over the past 34 yr attributable to human influences. Our results suggest that although coral communities existed around the subtropical islands of Daya Bay (southeast China) in the past, their continued presence in the region largely depends on appropriate management of the adjacent coastline and coupled ocean-atmosphere conditions similar to those experienced in the mid-Holocene.

This paper presents a reassessment of the archaeological record at Leang Burung 2, a key early human occupation site in the Late Pleistocene of Southeast Asia. Excavated originally by Ian Glover in 1975, this limestone rock-shelter in the Maros karsts of Sulawesi, Indonesia, has long held significance in our understanding of early human dispersals into 'Wallacea', the vast zone of oceanic islands between continental Asia and Australia. We present new stratigraphic information and dating evidence from Leang Burung 2 collected during the course of our excavations at this site in 2007 and 2011-13. Our findings suggest that the classic Late Pleistocene modern human occupation sequence identified previously at Leang Burung 2, and proposed to span around 31,000 to 19,000 conventional 14C years BP (~35-24 ka cal BP), may actually represent an amalgam of reworked archaeological materials. Sources for cultural materials of mixed ages comprise breccias from the rear wall of the rock-shelter-remnants of older, eroded deposits dated to 35-23 ka cal BP-and cultural remains of early Holocene antiquity. Below the upper levels affected by the mass loss of Late Pleistocene deposits, our deep-trench excavations uncovered evidence for an earlier hominin presence at the site. These findings include fossils of now-extinct proboscideans and other 'megafauna' in stratified context, as well as a cobble-based stone artifact technology comparable to that produced by late Middle Pleistocene hominins elsewhere on Sulawesi.

This paper presents a reassessment of the archaeological record at Leang Burung 2, a key early human occupation site in the Late Pleistocene of Southeast Asia. Excavated originally by Ian Glover in 1975, this limestone rock-shelter in the Maros karsts of Sulawesi, Indonesia, has long held significance in our understanding of early human dispersals into 'Wallacea', the vast zone of oceanic islands between continental Asia and Australia. We present new stratigraphic information and dating evidence from Leang Burung 2 collected during the course of our excavations at this site in 2007 and 2011-13. Our findings suggest that the classic Late Pleistocene modern human occupation sequence identified previously at Leang Burung 2, and proposed to span around 31,000 to 19,000 conventional 14C years BP (~35-24 ka cal BP), may actually represent an amalgam of reworked archaeological materials. Sources for cultural materials of mixed ages comprise breccias from the rear wall of the rock-shelter-remnants of older, eroded deposits dated to 35-23 ka cal BP-and cultural remains of early Holocene antiquity. Below the upper levels affected by the mass loss of Late Pleistocene deposits, our deep-trench excavations uncovered evidence for an earlier hominin presence at the site. These findings include fossils of now-extinct proboscideans and other 'megafauna' in stratified context, as well as a cobble-based stone artifact technology comparable to that produced by late Middle Pleistocene hominins elsewhere on Sulawesi.

Genetic evidence for anatomically modern humans (AMH) out of Africa before 75 thousand years ago (ka)1 and in island southeast Asia (ISEA) before 60 ka (93-61 ka)2 predates accepted archaeological records of occupation in the region3. Claims that AMH arrived in ISEA before 60 ka (ref. 4) have been supported only by equivocal5 or non-skeletal evidence6. AMH evidence from this period is rare and lacks robust chronologies owing to a lack of direct dating applications7, poor preservation and/or excavation strategies8 and questionable taxonomic identifications9. Lida Ajer is a Sumatran Pleistocene cave with a rich rainforest fauna associated with fossil human teeth7, 10. The importance of the site is unclear owing to unsupported taxonomic identification of these fossils and uncertainties regarding the age of the deposit, therefore it is rarely considered in models of human dispersal. Here we reinvestigate Lida Ajer to identify the teeth confidently and establish a robust chronology using an integrated dating approach. Using enamel-dentine junction morphology, enamel thickness and comparative morphology, we show that the teeth are unequivocally AMH. Luminescence and uranium-series techniques applied to bone-bearing sediments and speleothems, and coupled uranium-series and electron spin resonance dating of mammalian teeth, place modern humans in Sumatra between 73 and 63 ka. This age is consistent with biostratigraphic estimations7, palaeoclimate and sea-level reconstructions, and genetic evidence for a pre-60 ka arrival of AMH into ISEA2. Lida Ajer represents, to our knowledge, the earliest evidence of rainforest occupation by AMH, and underscores the importance of reassessing the timing and environmental context of the dispersal of modern humans out of Africa.

Wallacea, the zone of oceanic islands separating the continental regions of Southeast Asia and Australia, has yielded sparse evidence for the symbolic culture of early modern humans. Here we report evidence for symbolic activity 30,000-22,000 y ago at Leang Bulu Bettue, a cave and rock-shelter site on the Wallacean island of Sulawesi. We describe hitherto undocumented practices of personal ornamentation and portable art, alongside evidence for pigment processing and use in deposits that are the same age as dated rock art in the surrounding karst region. Previously, assemblages of multiple and diverse types of Pleistocene "symbolic" artifacts were entirely unknown from this region. The Leang Bulu Bettue assemblage provides insight into the complexity and diversification of modern human culture during a key period in the global dispersal of our species. It also shows that early inhabitants of Sulawesi fashioned ornaments from body parts of endemic animals, suggesting modern humans integrated exotic faunas and other novel resources into their symbolic world as they colonized the biogeographically unique regions southeast of continental Eurasia.

Genetic evidence for anatomically modern humans (AMH) out of Africa before 75 thousand years ago (ka)1 and in island southeast Asia (ISEA) before 60 ka (93-61 ka)2 predates accepted archaeological records of occupation in the region3. Claims that AMH arrived in ISEA before 60 ka (ref. 4) have been supported only by equivocal5 or non-skeletal evidence6. AMH evidence from this period is rare and lacks robust chronologies owing to a lack of direct dating applications7, poor preservation and/or excavation strategies8 and questionable taxonomic identifications9. Lida Ajer is a Sumatran Pleistocene cave with a rich rainforest fauna associated with fossil human teeth7, 10. The importance of the site is unclear owing to unsupported taxonomic identification of these fossils and uncertainties regarding the age of the deposit, therefore it is rarely considered in models of human dispersal. Here we reinvestigate Lida Ajer to identify the teeth confidently and establish a robust chronology using an integrated dating approach. Using enamel-dentine junction morphology, enamel thickness and comparative morphology, we show that the teeth are unequivocally AMH. Luminescence and uranium-series techniques applied to bone-bearing sediments and speleothems, and coupled uranium-series and electron spin resonance dating of mammalian teeth, place modern humans in Sumatra between 73 and 63 ka. This age is consistent with biostratigraphic estimations7, palaeoclimate and sea-level reconstructions, and genetic evidence for a pre-60 ka arrival of AMH into ISEA2. Lida Ajer represents, to our knowledge, the earliest evidence of rainforest occupation by AMH, and underscores the importance of reassessing the timing and environmental context of the dispersal of modern humans out of Africa.

Wallacea, the zone of oceanic islands separating the continental regions of Southeast Asia and Australia, has yielded sparse evidence for the symbolic culture of early modern humans. Here we report evidence for symbolic activity 30,000-22,000 y ago at Leang Bulu Bettue, a cave and rock-shelter site on the Wallacean island of Sulawesi. We describe hitherto undocumented practices of personal ornamentation and portable art, alongside evidence for pigment processing and use in deposits that are the same age as dated rock art in the surrounding karst region. Previously, assemblages of multiple and diverse types of Pleistocene "symbolic" artifacts were entirely unknown from this region. The Leang Bulu Bettue assemblage provides insight into the complexity and diversification of modern human culture during a key period in the global dispersal of our species. It also shows that early inhabitants of Sulawesi fashioned ornaments from body parts of endemic animals, suggesting modern humans integrated exotic faunas and other novel resources into their symbolic world as they colonized the biogeographically unique regions southeast of continental Eurasia.

Genetic evidence for anatomically modern humans (AMH) out of Africa before 75 thousand years ago (ka)1 and in island southeast Asia (ISEA) before 60 ka (93-61 ka)2 predates accepted archaeological records of occupation in the region3. Claims that AMH arrived in ISEA before 60 ka (ref. 4) have been supported only by equivocal5 or non-skeletal evidence6. AMH evidence from this period is rare and lacks robust chronologies owing to a lack of direct dating applications7, poor preservation and/or excavation strategies8 and questionable taxonomic identifications9. Lida Ajer is a Sumatran Pleistocene cave with a rich rainforest fauna associated with fossil human teeth7, 10. The importance of the site is unclear owing to unsupported taxonomic identification of these fossils and uncertainties regarding the age of the deposit, therefore it is rarely considered in models of human dispersal. Here we reinvestigate Lida Ajer to identify the teeth confidently and establish a robust chronology using an integrated dating approach. Using enamel-dentine junction morphology, enamel thickness and comparative morphology, we show that the teeth are unequivocally AMH. Luminescence and uranium-series techniques applied to bone-bearing sediments and speleothems, and coupled uranium-series and electron spin resonance dating of mammalian teeth, place modern humans in Sumatra between 73 and 63 ka. This age is consistent with biostratigraphic estimations7, palaeoclimate and sea-level reconstructions, and genetic evidence for a pre-60 ka arrival of AMH into ISEA2. Lida Ajer represents, to our knowledge, the earliest evidence of rainforest occupation by AMH, and underscores the importance of reassessing the timing and environmental context of the dispersal of modern humans out of Africa.

We investigated the evolution process of equilibrium lattice parameter (ELP), magnetic properties and electronic structure from nonmagnetic semiconductive CoFeTiAl to ferrimagnetic CoFeFeAl in theory and experiment. The theoretical results show that CoFe1+xTi1-xAl compounds have a diluted magnetism with a 100% spin-polarized ratio at the Fermi level when X is less than 30%. When X is in the range of 30%-60%, CoFe1+xTi1-xAl compounds have also a high spin-polarized ratio. The ELP and magnetization have a gradual and linear change with the increasing Fe level in the ranges of X = 0-50% and 70%-100%. An unexpected sharp jump in ELP and magnetization occurs near the composition point of X = 65%, which was attributed to band Jahn-Teller effect. In experiment, CoFe1+xTi1-xAl (X = 0, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% and 100%) compounds with Heusler structure were successfully synthesized. The experimental results are in agreement with the theoretical results when X is less than 30% or higher than 70%. The sharp jump in ELP and magnetization are experimentally observed near the composition point of 65%. The deviation of the experimental magnetization from theoretical results in the range of 50%-70% is attributed to the theoretical underestimation to ELP. We predict that by the same mechanism of the band Jahn-Teller effect, the sharp change in the magnetization and lattice parameter should also be possible to occur with the changing temperature for a certain composition of CoFe1+XTi1-XAl compounds. A new type of ferromagnetic shape memory alloys based on a martensitic transformation with an invariant crystallographic symmetry is proposed.

We investigated the evolution process of equilibrium lattice parameter (ELP), magnetic properties and electronic structure from nonmagnetic semiconductive CoFeTiAl to ferrimagnetic CoFeFeAl in theory and experiment. The theoretical results show that CoFe1+xTi1-xAl compounds have a diluted magnetism with a 100% spin-polarized ratio at the Fermi level when X is less than 30%. When X is in the range of 30%-60%, CoFe1+xTi1-xAl compounds have also a high spin-polarized ratio. The ELP and magnetization have a gradual and linear change with the increasing Fe level in the ranges of X = 0-50% and 70%-100%. An unexpected sharp jump in ELP and magnetization occurs near the composition point of X = 65%, which was attributed to band Jahn-Teller effect. In experiment, CoFe1+xTi1-xAl (X = 0, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% and 100%) compounds with Heusler structure were successfully synthesized. The experimental results are in agreement with the theoretical results when X is less than 30% or higher than 70%. The sharp jump in ELP and magnetization are experimentally observed near the composition point of 65%. The deviation of the experimental magnetization from theoretical results in the range of 50%-70% is attributed to the theoretical underestimation to ELP. We predict that by the same mechanism of the band Jahn-Teller effect, the sharp change in the magnetization and lattice parameter should also be possible to occur with the changing temperature for a certain composition of CoFe1+XTi1-XAl compounds. A new type of ferromagnetic shape memory alloys based on a martensitic transformation with an invariant crystallographic symmetry is proposed.

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 artefacts2, 3, 4 and remains of other extinct endemic fauna5, 6, were dated to between about 95 and 12 thousand calendar years (kyr) ago2, 3, 7. These ages suggested that H. floresiensis survived until long after modern humans reached Australia by ~50 kyr ago8, 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 Denisovans12, 13-is an open question.

Late Pleistocene raised coral reef terraces form extensive outcrops up to 5 km wide along the Saudi coast. Porites coral were dated using U/Th while clastic sediment from Jeddah was dated using thermoluminescence. The pooled mean age for the coral samples is 121.5 ± 0.2 ka suggesting MIS 5e, even for the uplifted 16-20 m high terrace in the north at Haql. In Jeddah the MIS 5e back-reef succession is overlain by fluvial sediment that gave a TL age of 66 ± 13 ka. The structure and faunal composition of the coral terraces suggests that they accumulated in broad shallow embayments following the last interglacial transgression. The consistent elevation of these terraces suggests that the central and southern Saudi coast has been tectonically stable for at least the past 125,000 years and the coral reef terraces (at 3.5-5.5 m elevation) are consistent with the MIS 5e sea level high-stand that peaked at 6-9 m above present sea level. The Saudi coastal coral terrace north of Duba shows progressive uplift to 16-20 m near Haql since 108-120 ka as a result of ongoing transform faulting in the Gulf of Aqaba.

We investigated the evolution process of equilibrium lattice parameter (ELP), magnetic properties and electronic structure from nonmagnetic semiconductive CoFeTiAl to ferrimagnetic CoFeFeAl in theory and experiment. The theoretical results show that CoFe1+xTi1-xAl compounds have a diluted magnetism with a 100% spin-polarized ratio at the Fermi level when X is less than 30%. When X is in the range of 30%-60%, CoFe1+xTi1-xAl compounds have also a high spin-polarized ratio. The ELP and magnetization have a gradual and linear change with the increasing Fe level in the ranges of X = 0-50% and 70%-100%. An unexpected sharp jump in ELP and magnetization occurs near the composition point of X = 65%, which was attributed to band Jahn-Teller effect. In experiment, CoFe1+xTi1-xAl (X = 0, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% and 100%) compounds with Heusler structure were successfully synthesized. The experimental results are in agreement with the theoretical results when X is less than 30% or higher than 70%. The sharp jump in ELP and magnetization are experimentally observed near the composition point of 65%. The deviation of the experimental magnetization from theoretical results in the range of 50%-70% is attributed to the theoretical underestimation to ELP. We predict that by the same mechanism of the band Jahn-Teller effect, the sharp change in the magnetization and lattice parameter should also be possible to occur with the changing temperature for a certain composition of CoFe1+XTi1-XAl compounds. A new type of ferromagnetic shape memory alloys based on a martensitic transformation with an invariant crystallographic symmetry is proposed.

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 artefacts2, 3, 4 and remains of other extinct endemic fauna5, 6, were dated to between about 95 and 12 thousand calendar years (kyr) ago2, 3, 7. These ages suggested that H. floresiensis survived until long after modern humans reached Australia by ~50 kyr ago8, 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 Denisovans12, 13-is an open question.

Late Pleistocene raised coral reef terraces form extensive outcrops up to 5 km wide along the Saudi coast. Porites coral were dated using U/Th while clastic sediment from Jeddah was dated using thermoluminescence. The pooled mean age for the coral samples is 121.5 ± 0.2 ka suggesting MIS 5e, even for the uplifted 16-20 m high terrace in the north at Haql. In Jeddah the MIS 5e back-reef succession is overlain by fluvial sediment that gave a TL age of 66 ± 13 ka. The structure and faunal composition of the coral terraces suggests that they accumulated in broad shallow embayments following the last interglacial transgression. The consistent elevation of these terraces suggests that the central and southern Saudi coast has been tectonically stable for at least the past 125,000 years and the coral reef terraces (at 3.5-5.5 m elevation) are consistent with the MIS 5e sea level high-stand that peaked at 6-9 m above present sea level. The Saudi coastal coral terrace north of Duba shows progressive uplift to 16-20 m near Haql since 108-120 ka as a result of ongoing transform faulting in the Gulf of Aqaba.

Knowledge of river sediment recycling provides important constraints on continent weathering and earth surface processes. In this study, we estimate the ¿comminution age¿ of sediments from the Changjiang (Yangtze River) and two small mountainous rivers in Taiwan based on their lithogenic (234U/238U) ratio. The (234U/238U) distributions in the Changjiang catchment are overall related to sediment grain size and chemical weathering regime, while (234U/238U) ratios in Taiwan rivers mainly depend on erosion/denudation processes. The comminution age constrains the time scale of sediment source-to-sink processes in catchments from sediment weathering/denudation to transportation, and finally deposition. Our results indicate that the comminution ages vary from 250 to 600 kyr for the Changjiang sediments and ~ 110 kyr for the Taiwan sediments. Different comminution ages are associated with contrasting erosion and weathering regimes and diverse topography between the large Changjiang catchment and small mountainous Taiwan basins. The longer comminution age of the Changjiang sediment is an interacting effect of a longer erosion/weathering history and sediment trapping effect (and thus slow transfer rate) created by broad floodplains and lakes in the middle and lower reaches. The shorter comminution age of the Taiwan sediment results from fast sediment denudation and transport associated with strong tectonic uplift, typhoon climate and steep topography. As these two major river systems dominate the sedimentology in East Asia continent margin, the distinct geological and topographical settings between the Changjiang and Taiwan river systems result in different sediment ¿source to sink¿ transport processes. This work presents a systematic and quantitative constraint on the time-scale of river sediment transfer process in East Asia, and also provides new insight into weathering regimes and sediment transport in monsoon climate-dominated continent and Island.

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 artefacts2, 3, 4 and remains of other extinct endemic fauna5, 6, were dated to between about 95 and 12 thousand calendar years (kyr) ago2, 3, 7. These ages suggested that H. floresiensis survived until long after modern humans reached Australia by ~50 kyr ago8, 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 Denisovans12, 13-is an open question.

Late Pleistocene raised coral reef terraces form extensive outcrops up to 5 km wide along the Saudi coast. Porites coral were dated using U/Th while clastic sediment from Jeddah was dated using thermoluminescence. The pooled mean age for the coral samples is 121.5 ± 0.2 ka suggesting MIS 5e, even for the uplifted 16-20 m high terrace in the north at Haql. In Jeddah the MIS 5e back-reef succession is overlain by fluvial sediment that gave a TL age of 66 ± 13 ka. The structure and faunal composition of the coral terraces suggests that they accumulated in broad shallow embayments following the last interglacial transgression. The consistent elevation of these terraces suggests that the central and southern Saudi coast has been tectonically stable for at least the past 125,000 years and the coral reef terraces (at 3.5-5.5 m elevation) are consistent with the MIS 5e sea level high-stand that peaked at 6-9 m above present sea level. The Saudi coastal coral terrace north of Duba shows progressive uplift to 16-20 m near Haql since 108-120 ka as a result of ongoing transform faulting in the Gulf of Aqaba.

We investigated the evolution process of equilibrium lattice parameter (ELP), magnetic properties and electronic structure from nonmagnetic semiconductive CoFeTiAl to ferrimagnetic CoFeFeAl in theory and experiment. The theoretical results show that CoFe1+xTi1-xAl compounds have a diluted magnetism with a 100% spin-polarized ratio at the Fermi level when X is less than 30%. When X is in the range of 30%-60%, CoFe1+xTi1-xAl compounds have also a high spin-polarized ratio. The ELP and magnetization have a gradual and linear change with the increasing Fe level in the ranges of X = 0-50% and 70%-100%. An unexpected sharp jump in ELP and magnetization occurs near the composition point of X = 65%, which was attributed to band Jahn-Teller effect. In experiment, CoFe1+xTi1-xAl (X = 0, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% and 100%) compounds with Heusler structure were successfully synthesized. The experimental results are in agreement with the theoretical results when X is less than 30% or higher than 70%. The sharp jump in ELP and magnetization are experimentally observed near the composition point of 65%. The deviation of the experimental magnetization from theoretical results in the range of 50%-70% is attributed to the theoretical underestimation to ELP. We predict that by the same mechanism of the band Jahn-Teller effect, the sharp change in the magnetization and lattice parameter should also be possible to occur with the changing temperature for a certain composition of CoFe1+XTi1-XAl compounds. A new type of ferromagnetic shape memory alloys based on a martensitic transformation with an invariant crystallographic symmetry is proposed.

Knowledge of river sediment recycling provides important constraints on continent weathering and earth surface processes. In this study, we estimate the ¿comminution age¿ of sediments from the Changjiang (Yangtze River) and two small mountainous rivers in Taiwan based on their lithogenic (234U/238U) ratio. The (234U/238U) distributions in the Changjiang catchment are overall related to sediment grain size and chemical weathering regime, while (234U/238U) ratios in Taiwan rivers mainly depend on erosion/denudation processes. The comminution age constrains the time scale of sediment source-to-sink processes in catchments from sediment weathering/denudation to transportation, and finally deposition. Our results indicate that the comminution ages vary from 250 to 600 kyr for the Changjiang sediments and ~ 110 kyr for the Taiwan sediments. Different comminution ages are associated with contrasting erosion and weathering regimes and diverse topography between the large Changjiang catchment and small mountainous Taiwan basins. The longer comminution age of the Changjiang sediment is an interacting effect of a longer erosion/weathering history and sediment trapping effect (and thus slow transfer rate) created by broad floodplains and lakes in the middle and lower reaches. The shorter comminution age of the Taiwan sediment results from fast sediment denudation and transport associated with strong tectonic uplift, typhoon climate and steep topography. As these two major river systems dominate the sedimentology in East Asia continent margin, the distinct geological and topographical settings between the Changjiang and Taiwan river systems result in different sediment ¿source to sink¿ transport processes. This work presents a systematic and quantitative constraint on the time-scale of river sediment transfer process in East Asia, and also provides new insight into weathering regimes and sediment transport in monsoon climate-dominated continent and Island.

The rapidly changing landscape of the eastern Indonesian archipelago has evolved at a pace dictated by its tropical climate and its geological and tectonic history. This has produced accelerated karstification, flights of alluvial terraces, and complex, multi-level cave systems. These cave systems sometimes contain a wealth of archaeological evidence, such as the almost complete skeleton of Homo floresiensis found at the site of Liang Bua in western Flores, but this information can only be understood in the context of the geomorphic history of the cave, and the more general geological, tectonic, and environmental histories of the river valley and region. Thus, a reconstruction of the landscape history of the Wae Racang valley using speleothems, geological structure, tectonic uplift, karst, cave, and terrace development, provides the necessary evidence to determine the formation, age, evolution, and influences on the site. This evidence suggests that Liang Bua was formed as two subterranean chambers 600 ka, but could not be occupied until 190 ka when the Wae Racang wandered to the southern side of the valley, exposing the chamber and depositing alluvial deposits containing artifacts. During the next 190 k.yr., the chambers coalesced and evolved into a multi-level and interconnected cave that was subjected to channel erosion and pooling events by the development of sinkholes. The domed morphology of the front chamber accumulated deep sediments containing well stratified archaeological and faunal remains, but ponded water in the chamber further prevented hominin use of the cave until 100 ka. These chambers were periodically influenced by river inundation and volcanic activity, whereas the area outside the cave was greatly influenced by glacial phases, which changed humid forest environments into grassland environments. This combined evidence has important implications for the archaeological interpretation of the site.

The rapidly changing landscape of the eastern Indonesian archipelago has evolved at a pace dictated by its tropical climate and its geological and tectonic history. This has produced accelerated karstification, flights of alluvial terraces, and complex, multi-level cave systems. These cave systems sometimes contain a wealth of archaeological evidence, such as the almost complete skeleton of Homo floresiensis found at the site of Liang Bua in western Flores, but this information can only be understood in the context of the geomorphic history of the cave, and the more general geological, tectonic, and environmental histories of the river valley and region. Thus, a reconstruction of the landscape history of the Wae Racang valley using speleothems, geological structure, tectonic uplift, karst, cave, and terrace development, provides the necessary evidence to determine the formation, age, evolution, and influences on the site. This evidence suggests that Liang Bua was formed as two subterranean chambers 600 ka, but could not be occupied until 190 ka when the Wae Racang wandered to the southern side of the valley, exposing the chamber and depositing alluvial deposits containing artifacts. During the next 190 k.yr., the chambers coalesced and evolved into a multi-level and interconnected cave that was subjected to channel erosion and pooling events by the development of sinkholes. The domed morphology of the front chamber accumulated deep sediments containing well stratified archaeological and faunal remains, but ponded water in the chamber further prevented hominin use of the cave until 100 ka. These chambers were periodically influenced by river inundation and volcanic activity, whereas the area outside the cave was greatly influenced by glacial phases, which changed humid forest environments into grassland environments. This combined evidence has important implications for the archaeological interpretation of the site.

The rapidly changing landscape of the eastern Indonesian archipelago has evolved at a pace dictated by its tropical climate and its geological and tectonic history. This has produced accelerated karstification, flights of alluvial terraces, and complex, multi-level cave systems. These cave systems sometimes contain a wealth of archaeological evidence, such as the almost complete skeleton of Homo floresiensis found at the site of Liang Bua in western Flores, but this information can only be understood in the context of the geomorphic history of the cave, and the more general geological, tectonic, and environmental histories of the river valley and region. Thus, a reconstruction of the landscape history of the Wae Racang valley using speleothems, geological structure, tectonic uplift, karst, cave, and terrace development, provides the necessary evidence to determine the formation, age, evolution, and influences on the site. This evidence suggests that Liang Bua was formed as two subterranean chambers 600 ka, but could not be occupied until 190 ka when the Wae Racang wandered to the southern side of the valley, exposing the chamber and depositing alluvial deposits containing artifacts. During the next 190 k.yr., the chambers coalesced and evolved into a multi-level and interconnected cave that was subjected to channel erosion and pooling events by the development of sinkholes. The domed morphology of the front chamber accumulated deep sediments containing well stratified archaeological and faunal remains, but ponded water in the chamber further prevented hominin use of the cave until 100 ka. These chambers were periodically influenced by river inundation and volcanic activity, whereas the area outside the cave was greatly influenced by glacial phases, which changed humid forest environments into grassland environments. This combined evidence has important implications for the archaeological interpretation of the site.

The rapidly changing landscape of the eastern Indonesian archipelago has evolved at a pace dictated by its tropical climate and its geological and tectonic history. This has produced accelerated karstification, flights of alluvial terraces, and complex, multi-level cave systems. These cave systems sometimes contain a wealth of archaeological evidence, such as the almost complete skeleton of Homo floresiensis found at the site of Liang Bua in western Flores, but this information can only be understood in the context of the geomorphic history of the cave, and the more general geological, tectonic, and environmental histories of the river valley and region. Thus, a reconstruction of the landscape history of the Wae Racang valley using speleothems, geological structure, tectonic uplift, karst, cave, and terrace development, provides the necessary evidence to determine the formation, age, evolution, and influences on the site. This evidence suggests that Liang Bua was formed as two subterranean chambers 600 ka, but could not be occupied until 190 ka when the Wae Racang wandered to the southern side of the valley, exposing the chamber and depositing alluvial deposits containing artifacts. During the next 190 k.yr., the chambers coalesced and evolved into a multi-level and interconnected cave that was subjected to channel erosion and pooling events by the development of sinkholes. The domed morphology of the front chamber accumulated deep sediments containing well stratified archaeological and faunal remains, but ponded water in the chamber further prevented hominin use of the cave until 100 ka. These chambers were periodically influenced by river inundation and volcanic activity, whereas the area outside the cave was greatly influenced by glacial phases, which changed humid forest environments into grassland environments. This combined evidence has important implications for the archaeological interpretation of the site.

Song Gupuh, a partially collapsed cave in the Gunung Sewu Limestones of East Java, Indonesia, contains over 16 m of deposits with a faunal sequence spanning some 70 ka. Major changes in the range of animals represented show the impact of climate change and humans. The Terminal Pleistocene and Early Holocene was a period of maximum biodiversity. Human use of Song Gupuh and other cave sites in the region also intensified significantly from ca. 12 ka, together with a new focus on exploitation of small-bodied species (macaque monkeys and molluscs), the first evidence for import of resources from the coast, and use of bone and shell tools. Human activity, especially after the onset of the Neolithic around 2.6 ka, subsequently contributed to a progressive loss of many species from the area, including tapir, elephant, Malayan bear, rhino and tiger, and this extinction process is continuing. We conclude by discussing the biogeographical significance of Song Gupuh in the context of other sites in Java (e.g. Punung, Wajak) and further afield (e.g. Liang Bua).

Song Gupuh, a partially collapsed cave in the Gunung Sewu Limestones of East Java, Indonesia, contains over 16 m of deposits with a faunal sequence spanning some 70 ka. Major changes in the range of animals represented show the impact of climate change and humans. The Terminal Pleistocene and Early Holocene was a period of maximum biodiversity. Human use of Song Gupuh and other cave sites in the region also intensified significantly from ca. 12 ka, together with a new focus on exploitation of small-bodied species (macaque monkeys and molluscs), the first evidence for import of resources from the coast, and use of bone and shell tools. Human activity, especially after the onset of the Neolithic around 2.6 ka, subsequently contributed to a progressive loss of many species from the area, including tapir, elephant, Malayan bear, rhino and tiger, and this extinction process is continuing. We conclude by discussing the biogeographical significance of Song Gupuh in the context of other sites in Java (e.g. Punung, Wajak) and further afield (e.g. Liang Bua).

Song Gupuh, a partially collapsed cave in the Gunung Sewu Limestones of East Java, Indonesia, contains over 16 m of deposits with a faunal sequence spanning some 70 ka. Major changes in the range of animals represented show the impact of climate change and humans. The Terminal Pleistocene and Early Holocene was a period of maximum biodiversity. Human use of Song Gupuh and other cave sites in the region also intensified significantly from ca. 12 ka, together with a new focus on exploitation of small-bodied species (macaque monkeys and molluscs), the first evidence for import of resources from the coast, and use of bone and shell tools. Human activity, especially after the onset of the Neolithic around 2.6 ka, subsequently contributed to a progressive loss of many species from the area, including tapir, elephant, Malayan bear, rhino and tiger, and this extinction process is continuing. We conclude by discussing the biogeographical significance of Song Gupuh in the context of other sites in Java (e.g. Punung, Wajak) and further afield (e.g. Liang Bua).

Reef development during past Interglacial periods, when sea level and sea surface temperatures were higher than today, provide unique insights into how reef systems may respond to projected human-induced global warming. Lord Howe Island currently represents the southernmost limit of reef development in the Pacific. Reef growth of Pleistocene age has been inferred to have occurred around the island, and this paper provides the fi rst detailed descriptions on the character of this development. Two phases of reef growth are identifi ed, which occurred as isolated fringing reefs along the edge of the basaltic hills of the island. Uranium-series dating indicates that the upper part of the sequence is of Last Interglacial age, however extensive calcite recrystallisation meant the lower part of the sequence does not yield reliable ages. Calcite cements suggest that several phases of recrystallisation have occurred meaning the lower part of the sequence is most likely to represent reef of Penultimate Interglacial age. Component analysis of the sedimentary matrix within the reef indicates coralline algae dominated sands which are very similar to the modern reef environment. This suggests that the environment at Lord Howe Island has remained at or close to the environmental limits for reef growth during the past few interglacials, despite lithospheric plate motion moving this island further north into reef building seas.

Reef development during past Interglacial periods, when sea level and sea surface temperatures were higher than today, provide unique insights into how reef systems may respond to projected human-induced global warming. Lord Howe Island currently represents the southernmost limit of reef development in the Pacific. Reef growth of Pleistocene age has been inferred to have occurred around the island, and this paper provides the fi rst detailed descriptions on the character of this development. Two phases of reef growth are identifi ed, which occurred as isolated fringing reefs along the edge of the basaltic hills of the island. Uranium-series dating indicates that the upper part of the sequence is of Last Interglacial age, however extensive calcite recrystallisation meant the lower part of the sequence does not yield reliable ages. Calcite cements suggest that several phases of recrystallisation have occurred meaning the lower part of the sequence is most likely to represent reef of Penultimate Interglacial age. Component analysis of the sedimentary matrix within the reef indicates coralline algae dominated sands which are very similar to the modern reef environment. This suggests that the environment at Lord Howe Island has remained at or close to the environmental limits for reef growth during the past few interglacials, despite lithospheric plate motion moving this island further north into reef building seas.

Reef development during past Interglacial periods, when sea level and sea surface temperatures were higher than today, provide unique insights into how reef systems may respond to projected human-induced global warming. Lord Howe Island currently represents the southernmost limit of reef development in the Pacific. Reef growth of Pleistocene age has been inferred to have occurred around the island, and this paper provides the fi rst detailed descriptions on the character of this development. Two phases of reef growth are identifi ed, which occurred as isolated fringing reefs along the edge of the basaltic hills of the island. Uranium-series dating indicates that the upper part of the sequence is of Last Interglacial age, however extensive calcite recrystallisation meant the lower part of the sequence does not yield reliable ages. Calcite cements suggest that several phases of recrystallisation have occurred meaning the lower part of the sequence is most likely to represent reef of Penultimate Interglacial age. Component analysis of the sedimentary matrix within the reef indicates coralline algae dominated sands which are very similar to the modern reef environment. This suggests that the environment at Lord Howe Island has remained at or close to the environmental limits for reef growth during the past few interglacials, despite lithospheric plate motion moving this island further north into reef building seas.

Reef development during past Interglacial periods, when sea level and sea surface temperatures were higher than today, provide unique insights into how reef systems may respond to projected human-induced global warming. Lord Howe Island currently represents the southernmost limit of reef development in the Pacific. Reef growth of Pleistocene age has been inferred to have occurred around the island, and this paper provides the fi rst detailed descriptions on the character of this development. Two phases of reef growth are identifi ed, which occurred as isolated fringing reefs along the edge of the basaltic hills of the island. Uranium-series dating indicates that the upper part of the sequence is of Last Interglacial age, however extensive calcite recrystallisation meant the lower part of the sequence does not yield reliable ages. Calcite cements suggest that several phases of recrystallisation have occurred meaning the lower part of the sequence is most likely to represent reef of Penultimate Interglacial age. Component analysis of the sedimentary matrix within the reef indicates coralline algae dominated sands which are very similar to the modern reef environment. This suggests that the environment at Lord Howe Island has remained at or close to the environmental limits for reef growth during the past few interglacials, despite lithospheric plate motion moving this island further north into reef building seas.

The degree to which Southern Hemisphere climatic changes during the end of the last glacial period and early Holocene (30-8 ka) were influenced or initiated by events occurring in the high latitudes of the Northern Hemisphere is a complex issue. There is conflicting evidence for the degree of hemispheric ‘teleconnection’ and an unresolved debate as to the principle forcing mechanism(s). The available hypotheses are difficult to test robustly, however, because the few detailed palaeoclimatic records in the Southern Hemisphere are widely dispersed and lack duplication. Here we present climatic and environmental reconstructions from across Australia, a key region of the Southern Hemisphere because of the range of environments it covers and the potentially important role regional atmospheric and oceanic controls play in global climate change.Weidentify a general scheme of events for the end of the last glacial period and early Holocene but a detailed reconstruction proved problematic. Significant progress in climate quantification and geochronological control is now urgently required to robustly investigate change through this period.

The degree to which Southern Hemisphere climatic changes during the end of the last glacial period and early Holocene (30-8 ka) were influenced or initiated by events occurring in the high latitudes of the Northern Hemisphere is a complex issue. There is conflicting evidence for the degree of hemispheric ‘teleconnection’ and an unresolved debate as to the principle forcing mechanism(s). The available hypotheses are difficult to test robustly, however, because the few detailed palaeoclimatic records in the Southern Hemisphere are widely dispersed and lack duplication. Here we present climatic and environmental reconstructions from across Australia, a key region of the Southern Hemisphere because of the range of environments it covers and the potentially important role regional atmospheric and oceanic controls play in global climate change.Weidentify a general scheme of events for the end of the last glacial period and early Holocene but a detailed reconstruction proved problematic. Significant progress in climate quantification and geochronological control is now urgently required to robustly investigate change through this period.

The degree to which Southern Hemisphere climatic changes during the end of the last glacial period and early Holocene (30-8 ka) were influenced or initiated by events occurring in the high latitudes of the Northern Hemisphere is a complex issue. There is conflicting evidence for the degree of hemispheric ‘teleconnection’ and an unresolved debate as to the principle forcing mechanism(s). The available hypotheses are difficult to test robustly, however, because the few detailed palaeoclimatic records in the Southern Hemisphere are widely dispersed and lack duplication. Here we present climatic and environmental reconstructions from across Australia, a key region of the Southern Hemisphere because of the range of environments it covers and the potentially important role regional atmospheric and oceanic controls play in global climate change.Weidentify a general scheme of events for the end of the last glacial period and early Holocene but a detailed reconstruction proved problematic. Significant progress in climate quantification and geochronological control is now urgently required to robustly investigate change through this period.

The degree to which Southern Hemisphere climatic changes during the end of the last glacial period and early Holocene (30-8 ka) were influenced or initiated by events occurring in the high latitudes of the Northern Hemisphere is a complex issue. There is conflicting evidence for the degree of hemispheric ‘teleconnection’ and an unresolved debate as to the principle forcing mechanism(s). The available hypotheses are difficult to test robustly, however, because the few detailed palaeoclimatic records in the Southern Hemisphere are widely dispersed and lack duplication. Here we present climatic and environmental reconstructions from across Australia, a key region of the Southern Hemisphere because of the range of environments it covers and the potentially important role regional atmospheric and oceanic controls play in global climate change.Weidentify a general scheme of events for the end of the last glacial period and early Holocene but a detailed reconstruction proved problematic. Significant progress in climate quantification and geochronological control is now urgently required to robustly investigate change through this period.