Articles de revues : « Early-Middle Pleistocene Transition »

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Peng, Xianzhe, Hong Ao, Guoqiao Xiao, Xiaoke Qiang et Qiang Sun. « The Early-Middle Pleistocene transition of Asian summer monsoon ». Palaeogeography, Palaeoclimatology, Palaeoecology 545 (mai 2020) : 109636. http://dx.doi.org/10.1016/j.palaeo.2020.109636.

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Maslin, Mark A., et Christopher M. Brierley. « The role of orbital forcing in the Early Middle Pleistocene Transition ». Quaternary International 389 (décembre 2015) : 47–55. http://dx.doi.org/10.1016/j.quaint.2015.01.047.

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Markova, Anastasia K. « Eastern European rodent (Rodentia, mammalia) faunas from the Early–Middle Pleistocene transition ». Quaternary International 131, n^o 1 (janvier 2005) : 71–77. http://dx.doi.org/10.1016/j.quaint.2004.07.020.

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Zieliński, Tomasz. « Prospects and limitations of heavy mineral analyses to discriminate preglacial/glacial transitions in Pleistocene sedimentary successions ». Geologos 24, n^o 2 (1 août 2018) : 151–62. http://dx.doi.org/10.2478/logos-2018-0014.

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Abstract The present study revolves around the identification of the stratigraphical boundary between Pleistocene formations that formed prior to the first advance of the Scandinavian ice sheet (Early Pleistocene, i.e., the so-called preglacial) and the overlying, glacially derived deposits (Middle Pleistocene). In particular, it focuses on variation in heavy mineral assemblages, which are an important tool for stratigraphers. The Neogene basement, described here, was most often the source of material that was redeposited by Early Pleistocene rivers. The geological structure and Early Pleistocene palaeogeographical scenarios for various Polish regions are discussed. Moreover, comparisons with other European preglacial formations are carried out. The mineral spectrum of Lower Pleistocene deposits is largely dependent of rocks of the Neogene and Mesozoic basement. If the incision of ancient catchments was into terrigenous rocks, the stratigraphical boundary between preglacial and glacial formations is easily determined with the help of a heavy mineral analysis. As a rule, this coincides with a noticeable change from resistant to non-resistant mineral associations. Such cases are noted for successions in central Poland and eastern England. On the other hand, outcrops of igneous or metamorphic rocks exist within preglacial river catchments in most parts of Europe. They were the local sources of non-resistant heavy minerals long before their glacial supply from the Baltic Shield. In these cases, mineralogical analysis fails in the search for the Early/Middle Pleistocene transition.

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Johnson, Kenneth G. « Middle Miocene recovery of Caribbean reef corals : New data from the Tamana Formation, Trinidad ». Journal of Paleontology 75, n^o 3 (mai 2001) : 513–26. http://dx.doi.org/10.1017/s0022336000039639.

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Caribbean coral reef communities were restructured by episodes of accelerated biotic change during the late Oligocene/early Miocene and the late Pliocene/early Pleistocene. However, rigorous description of the effects of rapid biotic change is problematic because preservation and exposure of coral-bearing deposits is not consistent in all stratigraphic intervals. In the Caribbean, early and middle Miocene exposures are more rare than late Miocene and Pliocene exposures. One exception is the late early to early middle Miocene Tamana Formation of Trinidad, and old and new collections from this unit were studied to determine the timing of recovery after the Oligocene/Miocene transition. A total of 41 species of zooxanthellate corals were recovered from the unit, including 21 new records. Within these assemblages, species first occurrences outnumber species last occurrences by a factor of four (31 first occurrences and eight last occurrences). The extension of the stratigraphic ranges of species previously first recorded in Pliocene sediments has reduced an apparent Pliocene pulse of origination, indicating that the Pliocene/Pleistocene transition was largely a result of accelerated extinction against a background of near-constant origination. The fact that few species last occur in the Tamana fauna indicates that the Oligocene/Miocene transition was complete by the end of the early Miocene.

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Marković, S. B., U. Hambach, T. Stevens, M. Jovanović, K. O'Hara-Dhand, B. Basarin, H. Lu et al. « Loess in the Vojvodina region (Northern Serbia) : an essential link between European and Asian Pleistocene environments ». Netherlands Journal of Geosciences - Geologie en Mijnbouw 91, n^o 1-2 (septembre 2013) : 173–88. http://dx.doi.org/10.1017/s0016774600001578.

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AbstractLoess deposits in the Vojvodina region, northern Serbia, are among the oldest and most complete loess-paleosol sequences in Europe to date. These thick sequences contain a detailed paleoclimatic record from the late Early Pleistocene. Based on the correlation of detailed magnetic susceptibility (MS) records from Vojvodina with the Chinese loess record and deep-sea isotope stratigraphy we here reconfirm and expand on a stratigraphic model of the Vojvodinian loess-paleosol chronostratigraphic sequence following the Chinese loess stratigraphic system.Variations in MS, dust accumulation rates, and the intensity of pedogenesis demonstrate evidence for a Middle Pleistocene climatic and environmental transition. The onset of loess deposition in Vojvodina also indicates a direct link between dust generation in Europe and that in the interior of Eurasia since the Early Pleistocene. The youngest part of the Early Pleistocene and oldest part of the Middle Pleistocene is characterised by relatively uniform dust accumulation and soil formation rates as well as relatively high magnetic susceptibility values. In contrast, the last five interglacial-glacial cycles are characterised by sharp environmental differences between high dust accumulation rates during the glacials and low rates observed during soil development. The data presented in this study demonstrate the great potential of Vovjodina's loess archives for accurate reconstruction of continental Eurasian Pleistocene climatic and environmental evolution.

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Head, Martin J., Brad Pillans et Sarah A. Farquhar. « The Early–Middle Pleistocene Transition : characterization and proposed guide for the defining boundary ». Episodes 31, n^o 2 (1 juin 2008) : 255–59. http://dx.doi.org/10.18814/epiiugs/2008/v31i2/014.

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Huuse, Mads. « Late Cenozoic palaeogeography of the eastern North Sea Basin : climatic vs tectonic forcing of basin margin uplift and deltaic progradation ». Bulletin of the Geological Society of Denmark 49 (2 décembre 2002) : 145–70. http://dx.doi.org/10.37570/bgsd-2003-49-12.

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The late Eocene to middle Pleistocene development of the eastern North Sea Basin is described by a series of palaeogeographic maps. The maps are based on published information integrated with recent investigations of seismic and well data from the eastern North Sea. The maps provide overviews of the basin geometry at late Eocene, late Oligocene, middle Miocene, late Miocene, late Pliocene and middle Pleistocene time. In post-Eocene time, the eastern and central North Sea Basin was progressively filled by large deltas, which built out from the eastern basin margin. These deltas were fed by ancient rivers from southern Norway (late Paleocene-Oligocene and Pliocene), southern Norway and Sweden (early Miocene), the Baltic region (middle Miocene-early Pleistocene), and finally by rivers flowing northward through the northwest European lowland (middle Pleistocene). It is argued that the Cenozoic evolution of the eastern North Sea Basin may be explained by a ‘self-perpetuating’ passive model. This model involves isostatic uplift of source areas due to erosional unloading of a relief generated by early Palaeogene uplift. The erosional unloading accelerated at the Eocene/Oligocene transition, in the middle Miocene and in the Plio-Pleistocene corresponding to periods of global climatic cooling and long-term eustatic lowering as indicated by δ18O records. The passive model diminishes the need for hypothetical Neogene tectonic events, although the influence of tectonic events cannot be excluded. Previous estimates of Neogene uplift and erosion of the northeastern Danish North Sea of the order of 500–1000 m do not agree with seismic geometries or with the regional palaeogeographic development. This indicates that previous estimates of Neogene uplift and erosion of the northeastern Danish North Sea may be several hundred metres too high.

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Martı́nez-Navarro, Bienvenido, et Maria Rita Palombo. « Occurrence of the Indian genusHemibos(Bovini, Bovidae, Mammalia) at the Early–Middle Pleistocene transition in Italy ». Quaternary Research 61, n^o 3 (mai 2004) : 314–17. http://dx.doi.org/10.1016/j.yqres.2004.02.002.

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The morphology of the horn-core structure and section shape of theBos galerianustype specimen, as well as the general anatomy of the frontal and occipital areas of the skull, suggest that the skull is better attributed to the Indian genusHemibos. This finding contributes to our understanding of faunal dispersal patterns into Europe at the Early–Middle Pleistocene transition.

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Bertini, Adele, Francesco Toti, Maria Marino et Neri Ciaranfi. « Vegetation and climate across the Early–Middle Pleistocene transition at Montalbano Jonico, southern Italy ». Quaternary International 383 (octobre 2015) : 74–88. http://dx.doi.org/10.1016/j.quaint.2015.01.003.

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Guillermic, Maxence, Sambuddha Misra, Robert Eagle et Aradhna Tripati. « Atmospheric CO2</sub&gt ; estimates for the Miocene to Pleistocene based on foraminiferal δ11B at Ocean Drilling Program Sites 806 and 807 in the Western Equatorial Pacific ». Climate of the Past 18, n^o 2 (2 février 2022) : 183–207. http://dx.doi.org/10.5194/cp-18-183-2022.

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Abstract. Constraints on the evolution of atmospheric CO2 levels throughout Earth's history are foundational to our understanding of past variations in climate. Despite considerable effort, records vary in their temporal and spatial coverage and estimates of past CO2 levels do not always converge, and therefore new records and proxies are valuable. Here we reconstruct atmospheric CO2 values across major climate transitions over the past 16 million years using the boron isotopic composition (δ11B) of planktic foraminifera from 89 samples obtained from two sites in the West Pacific Warm Pool, Ocean Drilling Program (ODP) Sites 806 and 807, measured using high-precision multi-collector inductively coupled plasma mass spectrometry. We compare our results to published data from ODP Site 872, also in the Western Equatorial Pacific, that goes back to 22 million years ago. These sites are in a region that today is near equilibrium with the atmosphere and are thought to have been in equilibrium with the atmosphere for the interval studied. We show that δ11B data from this region are consistent with other boron-based studies. The data show evidence for elevated pCO2 during the Middle Miocene and Early to Middle Pliocene, and reductions in pCO2 of ∼200 ppm during the Middle Miocene Climate Transition, ∼250 ppm during Pliocene Glacial Intensification and ∼50 ppm during the Mid-Pleistocene Climate Transition. During the Mid-Pleistocene Transition there is a minimum pCO2 at marine isotopic stage (MIS) 30. Our results are consistent with a coupling between pCO2, temperature and ice sheet expansion from the Miocene to the late Quaternary.

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Alexeeva, Nadezhda V., et Margarita A. Erbajeva. « Changes in the fossil mammal faunas of Western Transbaikalia during the Pliocene–Pleistocene boundary and the Early–Middle Pleistocene transition ». Quaternary International 131, n^o 1 (janvier 2005) : 109–15. http://dx.doi.org/10.1016/j.quaint.2004.07.002.

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Benvenuti, Marco, Jean-Jacques Bahain, Chiara Capalbo, Chiara Capretti, Francesco Ciani, Carmine D’Amico, Daniela Esu et al. « Paleoenvironmental context of the early Neanderthals of Poggetti Vecchi for the late middle Pleistocene of Central Italy ». Quaternary Research 88, n^o 2 (30 août 2017) : 327–44. http://dx.doi.org/10.1017/qua.2017.51.

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AbstractWork on thermal pools at Poggetti Vecchi in Grosseto, Italy, exposed an up to 3-meter-thick succession of seven sedimentary units. Unit 2 in the lower portion of the succession contained vertebrate bones, mostly of the straight-tusked elephant, Palaeoloxodon antiquus, commingled with stone, bone, and wooden tools. Thermal carbonates overlying Unit 2 are radiometrically dated to the latter part of the middle Pleistocene. This time span indicates that early Neanderthals produced the human artifacts from Poggetti Vecchi. The elephant bones belong to seven individuals of different ages. Sedimentary facies analysis and paleoecological evidence suggest a narrow lacustrine-palustrine embayment affected by water-level fluctuations and, at times, by hydrothermal water. Cyclic lake-level variations were predominantly forced by the rapid climatic fluctuations that occurred at Marine Isotope Stage (MIS) 6–7 transition and throughout the MIS 6. Possibly an abrupt, intense, and protracted cold episode during the onset of MIS 6 led to the sudden death of the elephants, which formed an unexpected food resource for the humans of the area. The Poggetti Vecchi site adds new information on the behavioral plasticity and food procurement strategies that early Neanderthals were able to develop in Italy during the middle to the late Pleistocene transition.

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Marino, Maria, Teresa Rodrigues, Ornella Quivelli, Angela Girone, Patrizia Maiorano et Franck Bassinot. « Paleoproductivity proxies and alkenone precursors in the Western Mediterranean during the Early-Middle Pleistocene transition ». Palaeogeography, Palaeoclimatology, Palaeoecology 601 (septembre 2022) : 111104. http://dx.doi.org/10.1016/j.palaeo.2022.111104.

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McNabb, John. « Hominins and the Early-Middle Pleistocene transition : evolution, culture and climate in Africa and Europe ». Geological Society, London, Special Publications 247, n^o 1 (2005) : 287–304. http://dx.doi.org/10.1144/gsl.sp.2005.247.01.17.

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Wattanapituksakul, Athiwat, Rasmi Shoocongdej et Cyler Conrad. « Preservation of Mammalian Teeth and Bones Influences Identification of Terminal Pleistocene to Middle Holocene Hunter-Gatherer Subsistence at Ban Rai Rockshelter, Northwest Thailand ». Quaternary 5, n^o 4 (6 décembre 2022) : 51. http://dx.doi.org/10.3390/quat5040051.

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Ban Rai Rockshelter in northwest Thailand, dating to the Terminal Pleistocene and Middle Holocene, includes evidence for hunter-gatherer exploitation of mammals, birds, reptiles, fish, and arthropods. Abundant faunal remains, identified throughout site deposits, include macaques (Macaca sp.) and Sambar deer (Rusa unicolor), but these identifications are influenced by an assemblage largely comprised of preserved tooth elements and fragmented bone. Area 3 at Ban Rai has the largest abundance and diversity of faunal remains recovered and identified in this study. Here, we examine the zooarchaeological assemblage from Ban Rai Rockshelter, to understand long-term hunter-gatherer subsistence change, influenced by site preservation, during and after the Pleistocene–Holocene transition. Our results support the presence of the exploitation of arboreal taxa during the Early and Middle Holocene in northwest Thailand.

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Hughes, Philip D., Philip L. Gibbard et Jürgen Ehlers. « The “missing glaciations” of the Middle Pleistocene ». Quaternary Research 96 (4 février 2020) : 161–83. http://dx.doi.org/10.1017/qua.2019.76.

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AbstractGlobal glaciations have varied in size and magnitude since the Early–Middle Pleistocene transition (~773 ka), despite the apparent regular and high-amplitude 100 ka pacing of glacial–interglacial cycles recorded in marine isotope records. The evidence on land indicates that patterns of glaciation varied dramatically between different glacial–interglacial cycles. For example, Marine Isotope Stages (MIS) 8, 10, and 14 are all noticeably absent from many terrestrial glacial records in North America and Europe. However, globally, the patterns are more complicated, with major glaciations recorded in MIS 8 in Asia and in parts of the Southern Hemisphere, such as Patagonia, for example. This spatial variability in glaciation between glacial–interglacial cycles is likely to be driven by ice volume changes in the West Antarctic Ice Sheet and associated interhemispheric connections through ocean–atmosphere circulatory changes. The weak global glacial imprint in some glacial–interglacial cycles is related to the pattern of global ice buildup. This is caused by feedback mechanisms within glacial systems themselves that partly result from long-term orbital changes driven by eccentricity.

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Wu, Xiu-Jie, Shu-Wen Pei, Yan-Jun Cai, Hao-Wen Tong, Qiang Li, Zhe Dong, Jin-Chao Sheng et al. « Archaic human remains from Hualongdong, China, and Middle Pleistocene human continuity and variation ». Proceedings of the National Academy of Sciences 116, n^o 20 (29 avril 2019) : 9820–24. http://dx.doi.org/10.1073/pnas.1902396116.

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Middle to Late Pleistocene human evolution in East Asia has remained controversial regarding the extent of morphological continuity through archaic humans and to modern humans. Newly found ∼300,000-y-old human remains from Hualongdong (HLD), China, including a largely complete skull (HLD 6), share East Asian Middle Pleistocene (MPl) human traits of a low vault with a frontal keel (but no parietal sagittal keel or angular torus), a low and wide nasal aperture, a pronounced supraorbital torus (especially medially), a nonlevel nasal floor, and small or absent third molars. It lacks a malar incisure but has a large superior medial pterygoid tubercle. HLD 6 also exhibits a relatively flat superior face, a more vertical mandibular symphysis, a pronounced mental trigone, and simple occlusal morphology, foreshadowing modern human morphology. The HLD human fossils thus variably resemble other later MPl East Asian remains, but add to the overall variation in the sample. Their configurations, with those of other Middle and early Late Pleistocene East Asian remains, support archaic human regional continuity and provide a background to the subsequent archaic-to-modern human transition in the region.

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Arauza, Hanna M., Alexander R. Simms, Leland C. Bement, Brian J. Carter, Travis Conley, Ammanuel Woldergauy, William C. Johnson et Priyank Jaiswal. « Geomorphic and sedimentary responses of the Bull Creek Valley (Southern High Plains, USA) to Pleistocene and Holocene environmental change ». Quaternary Research 85, n^o 1 (janvier 2016) : 118–32. http://dx.doi.org/10.1016/j.yqres.2015.11.006.

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Fluvial geomorphology and stratigraphy often reflect past environmental and climate conditions. This study examines the response of Bull Creek, a small ephemeral creek in the Oklahoma panhandle, to environmental conditions through the late Pleistocene and Holocene. Fluvial terraces were mapped and their stratigraphy and sedimentology documented throughout the course of the main valley. Based on their elevations, terraces were broadly grouped into a late-Pleistocene fill terrace (T3) and two Holocene fill-cut terrace sets (T2 and T1). Terrace systems are marked by similar stratigraphies recording the general environmental conditions of the time. Sedimentary sequences preserved in terrace fills record the transition from a perennial fluvial system during the late glacial period and the Younger Dryas to a semiarid environment dominated by loess accumulation and punctuated by flood events during the middle to late Holocene. The highest rates of aeolian accumulation within the valley occurred during the early to middle Holocene. Our data provide significant new information regarding the late-Pleistocene and Holocene environmental history for this region, located between the well-studied Southern and Central High Plains of North America.

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Lubell, David. « Are land snail a signature for the Mesolithic-Neolithic transition ». Documenta Praehistorica 31 (31 décembre 2004) : 1–24. http://dx.doi.org/10.4312/dp.31.1.

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Edible land snails, representing food remains, are frequently very abundant in late Pleistocene and early-middle Holocene archaeological sites throughout the circum-Mediterranean region. As such, they appear to represent a signature for a broad spectrum subsistence base as first conceived by Flannery in 1969, and therefore must be in some way related to the transition from foraging to food production. This paper investigates the implications that can be drawn from the presence of these snails through information on their ecology, biology, behaviour and nutritional value as well as the behaviour of the prehistoric human groups who collected and consumed them.

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Duval, Mathieu, Lee J. Arnold, Josep M. Parés et Dirk L. Hoffmann. « The Jaramillo Subchron and the Early-Middle Pleistocene transition in continental records from a multidisciplinary perspective ». Quaternary International 389 (décembre 2015) : 1–6. http://dx.doi.org/10.1016/j.quaint.2015.09.018.

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Salehi, Tayebe. « Population genetic structure of the endangered yellow spotted mountain newt (Neurergus derjugini : Amphibia, Caudata) inferred from mitochondrial DNA sequences ». January 2019, Volume 29, Number 1 (1 janvier 2019) : 37–47. http://dx.doi.org/10.33256/hj29.1.3747.

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The yellow spotted mountain newt (Neurergus derjugini) is a critically endangered species restricted to fragmented habitats in highland streams of the middle Zagros Mountain in Iran and Iraq. We examined the species phylogeography by investigating sequences of a mitochondrial fragment of the ND2 gene for 77 individuals from 15 locations throughout the species known distribution. We found relatively high haplotype diversity (0.82 ± 0.025) but low nucleotide diversity (0.0038 ± 0.00022) across all populations. Phylogenetic trees supported monophyly, and the segregation of haplotypes was concordant with the haplotype network. We found a significant correlation between geographical and genetic distances among populations (r = 0.54, P ˂ 0.01), suggesting restricted gene flow. Molecular dating suggested that haplogroups diverged during the early or middle Pleistocene. Bayesian skyline plot provided evidence for an expansion of populations during the Pleistocene-Holocene transition period. Taken together, isolation by distance due to low dispersal capability, habitat fragmentation, and historical factors have shaped the current population structure of N. derjugini.

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Shipton, C. « Hierarchical Organization in the Acheulean to Middle Palaeolithic Transition at Bhimbetka, India ». Cambridge Archaeological Journal 26, n^o 4 (25 octobre 2016) : 601–18. http://dx.doi.org/10.1017/s095977431600041x.

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The transition from the Acheulean to the Middle Palaeolithic represents a critical threshold in human evolution when archaic behaviour patterns gave way to the Levallois stone tool technology that characterizes later Pleistocene hominins including Homo neanderthalensis and early Homo sapiens. This article examines that transition through a comparative perspective on handaxes and cleavers (collectively referred to here as bifaces) from the site of Bhimbetka in central India. The Bhimbetka bifaces are compared to those from Patpara, another transitional assemblage in central India, as well as non-transitional Indian Acheulean assemblages. Bhimbetka and Patpara share unusually refined bifaces. While this refinement is attributed to invasive flaking at Patpara, at Bhimbetka it appears to be related to the ability to strike large thin flake blanks. These both have consequences for biface symmetry, with Patpara handaxes being particularly symmetrical in profile, while Bhimbetka cleavers are particularly symmetrical in section. Unlike Patpara, most of the Bhimbetka bifaces have not undergone resharpening. However, cleavers from the two sites do share unusually high rates of damage on their bits and the occasional use of cleavers as notches. It is argued that, while the transition at the two sites occurred independently, it was underpinned by the same cognitive pattern: an increased capacity for hierarchical organization.

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Palombo, Maria R., et Andrea M. F. Valli. « Highlighting the Early-Middle Pleistocene transition in Italian and French large-mammal faunas : similarities and faunal renewals ». Geological Society, London, Special Publications 247, n^o 1 (2005) : 263–76. http://dx.doi.org/10.1144/gsl.sp.2005.247.01.15.

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Boulygina, Eugenia, Fedor Sharko, Maksim Cheprasov, Maria Gladysheva-Azgari, Natalia Slobodova, Svetlana Tsygankova, Sergey Rastorguev et al. « Ancient DNA Reveals Maternal Philopatry of the Northeast Eurasian Brown Bear (Ursus arctos) Population during the Holocene ». Genes 13, n^o 11 (27 octobre 2022) : 1961. http://dx.doi.org/10.3390/genes13111961.

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Significant palaeoecological and paleoclimatic changes that took place during Late Pleistocene—Early Holocene transition are considered important factors that led to megafauna extinctions. Unlike many other species, the brown bear (Ursus arctos) has survived this geological time. Despite the fact that several mitochondrial DNA clades of brown bears became extinct at the end of the Pleistocene, this species is still widely distributed in Northeast Eurasia. Here, using the ancient DNA analysis of a brown bear individual that inhabited Northeast Asia in the Middle Holocene (3460 ± 40 years BP) and comparative phylogenetic analysis, we show a significant mitochondrial DNA similarity of the studied specimen with modern brown bears inhabiting Yakutia and Chukotka. In this study, we clearly demonstrate the maternal philopatry of the Northeastern Eurasian U. arctos population during the several thousand years of the Holocene.

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Thompson, Jessica C., David K. Wright, Sarah J. Ivory, Jeong-Heon Choi, Sheila Nightingale, Alex Mackay, Flora Schilt et al. « Early human impacts and ecosystem reorganization in southern-central Africa ». Science Advances 7, n^o 19 (mai 2021) : eabf9776. http://dx.doi.org/10.1126/sciadv.abf9776.

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Modern Homo sapiens engage in substantial ecosystem modification, but it is difficult to detect the origins or early consequences of these behaviors. Archaeological, geochronological, geomorphological, and paleoenvironmental data from northern Malawi document a changing relationship between forager presence, ecosystem organization, and alluvial fan formation in the Late Pleistocene. Dense concentrations of Middle Stone Age artifacts and alluvial fan systems formed after ca. 92 thousand years ago, within a paleoecological context with no analog in the preceding half-million-year record. Archaeological data and principal coordinates analysis indicate that early anthropogenic fire relaxed seasonal constraints on ignitions, influencing vegetation composition and erosion. This operated in tandem with climate-driven changes in precipitation to culminate in an ecological transition to an early, pre-agricultural anthropogenic landscape.

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Agusti, Jorge, Oriol Oms et Josep M. Pares. « Calibration of the Early-Middle Pleistocene transition in the continental beds of the Guadix–Baza Basin (SE Spain) ». Quaternary Science Reviews 18, n^o 12 (octobre 1999) : 1409–17. http://dx.doi.org/10.1016/s0277-3791(98)00116-4.

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Cuenca-Bescós, G., J. Rofes et J. Garcia-Pimienta. « Environmental change across the Early-Middle Pleistocene transition : small mammalian evidence from the Trinchera Dolina cave, Atapuerca, Spain ». Geological Society, London, Special Publications 247, n^o 1 (2005) : 277–86. http://dx.doi.org/10.1144/gsl.sp.2005.247.01.16.

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Barendregt, R. W., et Jean-Serge Vincent. « Late Cenozoic paleomagnetic record of Duck Hawk Bluffs, Banks Island, Canadian Arctic Archipelago ». Canadian Journal of Earth Sciences 27, n^o 1 (1 janvier 1990) : 124–30. http://dx.doi.org/10.1139/e90-010.

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Detailed paleomagnetic investigations have been completed on unconsolidated sediments from Duck Hawk Bluffs on Banks Island, in the Canadian Arctic Archipelago, that record some of the oldest late Cenozoic glacial and nonglacial events in Canada. The preglacial Worth Point Formation, the overlying Duck Hawk Bluffs Formation, including marine and glacial deposits laid down during the Banks Glaciation, and the lower part of the interglacial Morgan Bluffs Formation have magnetically reversed directions and therefore are of Matuyama age (>790 ka). Upper Morgan Bluffs Formation organic beds and deposits of the younger Thomsen Glaciation, Cape Collinson Interglaciation, and Amundsen Glaciation are normally magnetized and therefore of Brunhes age (<790 ka). The Brunhes–Matuyama boundary is recorded in the upper portion of the Morgan Bluffs Formation. Its precise position within the interglacial sequence can be identified, since the sediments document the gradual change from reversely inclined directions to normally inclined ones. These results confirm that the preglacial Worth Point Formation is at least Early Pleistocene in age and that the Banks Glaciation (the oldest and strongest continental glaciation recorded in the western Arctic) and a good part of the Morgan Bluffs Formation are of Early Pleistocene age. The study also documents a rare site in Canada where terrestrial sediments record the Brunhes–Matuyama transition and in doing so permits a precise correlation of part of the Banks Island stratigraphy with other key late Tertiary and Early to Middle Pleistocene arctic terrestrial and marine sequences.

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Lozhkin, Anatoly V., Patricia M. Anderson, Pavel S. Minyuk, Julia A. Korzun, Ekaterina Y. Nedorubova et Mariana A. Kirillova. « Environmental changes in Arctic Chukotka during Marine Isotope Stages 38‐31 : implications for the Early to Middle Pleistocene transition ». Boreas 49, n^o 1 (8 octobre 2019) : 168–80. http://dx.doi.org/10.1111/bor.12413.

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Martínez-Navarro, Bienvenido, et Rivka Rabinovich. « The fossil Bovidae (Artiodactyla, Mammalia) from Gesher Benot Ya‘aqov, Israel : Out of Africa during the Early–Middle Pleistocene transition☆ ». Journal of Human Evolution 60, n^o 4 (avril 2011) : 375–86. http://dx.doi.org/10.1016/j.jhevol.2010.03.012.

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Dodonov, A. E. « The stratigraphic transition and suggested boundary between the Early and Middle Pleistocene in the loess record of northern Eurasia ». Geological Society, London, Special Publications 247, n^o 1 (2005) : 209–19. http://dx.doi.org/10.1144/gsl.sp.2005.247.01.11.

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Barham, Lawrence, Stephen Tooth, Geoff A. T. Duller, Andrew J. Plater et Simon Turner. « Excavations at Site C North, Kalambo Falls, Zambia : New Insights into the Mode 2/3 Transition in South-Central Africa ». Journal of African Archaeology 13, n^o 2 (1 novembre 2015) : 187–214. http://dx.doi.org/10.3213/2191-5784-10270.

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We report on the results of small-scale excavations at the archaeological site of Kalambo Falls, northern Zambia. The site has long been known for its stratified succession of Stone Age horizons, in particular those representing the late Acheulean (Mode 2) and early Middle Stone Age (Mode 3). Previous efforts to date these horizons have provided, at best, minimum radiometric ages. The absence of a firm chronology for the site has limited its potential contribution to our understanding of the process of technological change in the Middle Pleistocene of south-central Africa. The aim of the excavations was to collect samples for luminescence dating that bracketed archaeological horizons, and to establish the sedimentary and palaeoenvironmental contexts of the deposits. Four sedimentary packages were identified with the oldest containing Mode 2 and Mode 3 horizons. In this paper we consider the implications of the luminescence ages for the archaeological record at Kalambo Falls, and place them in a regional context. The reworking and preservation of the archaeological horizons is interpreted as the result of successive phases of meander migration and aggradation. Limited pollen evidence suggests a persistent floodplain palaeoenvironment with intermittent swamp forest and adjacent valley woodland, while mineral magnetic susceptibility data support an interpretation of river flow variability without any significant change in sediment provenance. The dynamics of the fluvial system cannot as yet be linked directly with regional climate change. The age range of ~500–300 ka for the oldest sedimentary package places the Mode 2/3 succession firmly in the Middle Pleistocene, and contributes to an expanding African record of technological innovation before the evolution of Homo sapiens.

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Barton, R. N. E., A. Bouzouggar et C. B. Stringer. « Bridging the gap : new fieldwork in northern Morocco ». Antiquity 75, n^o 289 (septembre 2001) : 489–90. http://dx.doi.org/10.1017/s0003598x0008858x.

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The question of human contacts between Africa and the Iberian Peninsula in the Middle and Upper Pleistocene is of key interest in research of human origins. Discussion continues to focus on whether the sea gap separating the landmasses proved an effective barrier to cultural interchange and population movements. At its narrowest point the Gibraltar Strait is no more than 14 km wide and at times of lower sea level in the Pleistocene the gap would have been considerably reduced by the exposure of several offshore islands. Such sea crossings were apparently well within the capabilities of early human colonizers, as shown by the 800,000-year-old occupation of islands in the Indonesian archipelago. Despite these observations, many archaeologists have pointed to the ostensible lack of evidence for human interactions between Europe and North Africa until some time in the Upper Palaeolithic. This is surprising, given the presence of populations in both areas from the Lower Palaeolithic onwards. Such an ‘isolationist’ view is emphasized by the recent work of the Gibraltar Caves Project (Barton et al. 1999; Stringer et al. 2000) which has shown that Neanderthal populations with Middle Palaeolithic technology lived there until at least 32,000 years ago uncal, at a time when anatomically modern humans were already present elsewhere in Europe and Africa. Until now, no evidence of Neanderthals has been found in North Africa but the dating and nature of the Middle to Upper Palaeolithic transition in this region remains poorly understood.

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Matviishyna, Zh M., et S. P. Doroshkevych. « Micromorphological peculiarities of the Pleistocene soils in the Middle Pobuzhzhya (Ukraine) and their significance for paleogeographic reconstructions ». Journal of Geology, Geography and Geoecology 28, n^o 2 (6 juillet 2019) : 327–47. http://dx.doi.org/10.15421/111932.

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The basic micromorphological features of fossil Pleistocene soils of the Middle Pobuzhzhya region are revealed. The early Neopleistocene (Shyrokyne, Martonosha, Lubny) and Middle Pleistocene Zavadivka soils are characterized by bright brownish, reddish and brownish colors of plasma, compact composing structural separations in the form of cleave blocks with densely packed nodular formations of ferruginous matter, cracksman ship of the mass, a significantamount of ferruginous, manganese and carbonate new formations. In the soils of the early optimum of the Kaydaky stage, signs of the eluvial-illuvial processes were observed (impoverished on the thin clays and humus fields with the «washed» grains of the mineral skeleton, the destroyed microaggregates in the eluvial and the impregnation of the plasma by calomorphic clays in the form of streaks, films, streams in the illuvial horizons). In the Pryluky soils there is a well-expressed microagregation of the mass, a branched net of twisted pores, humus coagulation in the humus and humus transition horizons, various forms of carbonate new formations as the impregnation and plasma cementation by microcrystalline calcite, presence of isolated crystals of crypto-, micro- and small crystalline calcite. The specific individual features of the Vytachiv soils are cleave block microstructure, the presence of the nodular concentric organo-iron-clay formations, and microorsteins. Dofinivka soils are characterized by a loose microstructure, fuzzy rounded microaggregates, a developed system of twisted pores, and enrichment of mass on carbonates. In order to clarify the genetic types of fossil Pleistocene soils of the Middle Pobuzhzhya, identification of the signs of elementary soil formation processes was carried out on the basis of micromorphological analysis data. The significance of the results of micromorphological researches for paleogeographical reconstruction is outlined. It has been established that certain groups of soil formation processes are characteristic for fossil soils of separate paleogeographical stages. In the soils formed up to the Dnieper glaciation (Shyrokyne, Martonosha, Lubny and Zavadivka), signs of processes of claying, rubbification, ferralization, cleaving were displayed, but weakly expressed humus formation, thoughcarbonization were diagnosed. In the soils formed after the maximum glaciation (Kaydaky, Pryluky, Vytachiv, Dofinivka), signs of the such processes as humus formation, podzolization, lessive, leaching, damp-meadow soil formation on floodplain, migration of carbonates, etc., are established. It is processes which are predominating in the modern soils of the territory of Ukraine. Assertaintment of elementary soil-forming processes, diagnosed in multi-annual fossil soils, have made it possible to identify their genetic types and as a result, to reconstruct the soil cover in separate stages of the Neopleistocene, to establish regional patterns of evolutional stadial changes and the natural environment in the Pleistocene on the territory of the Middle Pobuzhzhya.

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Orain, R., V. Lebreton, E. Russo Ermolli, A. M. Sémah, S. Nomade, Q. Shao, J. J. Bahain, U. Thun Hohenstein et C. Peretto. « Hominin responses to environmental changes during the Middle Pleistocene in central and southern Italy ». Climate of the Past 9, n^o 2 (14 mars 2013) : 687–97. http://dx.doi.org/10.5194/cp-9-687-2013.

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Abstract. The palaeobotanical record of early Palaeolithic sites from Western Europe indicates that hominins settled in different kinds of environments. During the "mid-Pleistocene transition (MPT)", from about 1 to 0.6 Ma, the transition from 41- to 100-ka dominant climatic oscillations, occurring within a long-term cooling trend, was associated with an aridity crisis which strongly modified the ecosystems. Starting from the MPT the more favourable climate of central and southern Italy provided propitious environmental conditions for long-term human occupations even during the glacial times. In fact, the human strategy of territory occupation was certainly driven by the availabilities of resources. Prehistoric sites such as Notarchirico (ca. 680–600 ka), La Pineta (ca. 600–620 ka), Guado San Nicola (ca. 380–350 ka) or Ceprano (ca. 345–355 ka) testify to a preferential occupation of the central and southern Apennines valleys during interglacial phases, while later interglacial occupations were oriented towards the coastal plains, as attested by the numerous settlements of the Roma Basin (ca. 300 ka). Faunal remains indicate that human subsistence behaviours benefited from a diversity of exploitable ecosystems, from semi-open to closed environments. In central and southern Italy, several palynological records have already illustrated the regional- and local-scale vegetation dynamic trends. During the Middle Pleistocene climate cycles, mixed mesophytic forests developed during the interglacial periods and withdrew in response to increasing aridity during the glacial episodes. New pollen data from the Boiano Basin (Molise, Italy) attest to the evolution of vegetation and climate between MIS 13 and 9 (ca. 500 to 300 ka). In this basin the persistence of high edaphic humidity, even during the glacial phases, could have favoured the establishment of a refuge area for the arboreal flora and provided subsistence resources for the animal and hominin communities during the Middle Pleistocene. This could have constrained human groups to migrate into such a propitious area. Regarding the local climate evolution during the glacial episodes, the supposed displacement from these sites could be linked to the environmental dynamics solely due to the aridity increase, rather than directly to the global climate changes.

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Orain, R., V. Lebreton, E. Russo Ermolli, A. M. Sémah, S. Nomade, Q. Shao, J. J. Bahain, U. Thun Hohenstein et C. Peretto. « Hominin responses to environmental changes during the Middle Pleistocene in Central and Southern Italy ». Climate of the Past Discussions 8, n^o 5 (23 octobre 2012) : 5181–207. http://dx.doi.org/10.5194/cpd-8-5181-2012.

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Abstract. The palaeobotanical record of early Palaeolithic sites from Western Europe indicates that hominins settled in different kinds of environments. During the "Mid-Pleistocene Transition (MPT)", from about 1 to 0.6 Ma, the transition from 41-ka to 100-ka dominant climatic oscillations, occurring within a long-term cooling trend, was associated with an aridity crisis which strongly modified the ecosystems. Starting from the MPT the more favorable climate of central and southern Italy provided propitious environmental conditions for long-term human occupations even during the glacial times. In fact, the human strategy of territory occupation was certainly driven by the availabilities of resources. Prehistoric sites such as Notarchirico (ca. 680–600 ka), La Pineta (ca. 600–620 ka), Gaudo San Nicola (ca. 380–350 ka) or Ceprano (ca. 345–355 ka) testify to a preferential occupation of the central and southern Apennines valleys during interglacial phases, while later interglacial occupations were oriented towards the coastal plains, as attested by the numerous settlements of the Roma basin (ca. 300 ka). Faunal remains indicate that human subsistence behaviors benefited of a diversity of exploitable ecosystems, from semi-open to closed environments. In central and southern Italy, several palynological records have already illustrated the regional and local scale vegetation dynamic trends. During the Middle Pleistocene climate cycles, mixed mesophytic forests developed during the interglacial periods and withdrew in response to increasing aridity during the glacial episodes. New pollen data from the Boiano basin (Molise, Italy), attest to the evolution of vegetation and climate between OIS 13 and 9 (ca. 500 to 300 ka). In this basin, the persistence of high edaphic humidity, even during the glacial phases, could have favored the establishment of a refuge area for the arboreal flora and provided subsistence resources for the animal and hominin communities during the Middle Pleistocene. This could have constrained human groups to migrate into such a propitious area. Regarding to the local climate evolution during the glacial episodes, the supposed displacement from these sites could be linked to the environmental dynamics solely due to the aridity increase rather than directly to the global climate changes.

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Demezhko, D. Y., et A. A. Gornostaeva. « Geothermal evidence of the Late Pleistocene-Holocene orbital forcing (example from the Urals, Russia) ». Climate of the Past Discussions 10, n^o 4 (29 août 2014) : 3617–29. http://dx.doi.org/10.5194/cpd-10-3617-2014.

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Abstract. We use early obtained in the Middle Urals geothermal reconstruction of the ground surface temperature (GST) history to determine the surface heat flux (SHF) history over the past 35 kyr. A new algorithm of GST-SHF transformation was applied to solve this problem. The time scale of geothermal reconstructions has been corrected by comparing the estimated heat flux and annual insolation at the latitude of 60° N. The consistency of SHF and insolation changes on the interval 35–6 kyr BP (the linear correlation coefficient R = 0.99) points to orbital factors as the main cause of climatic changes during the Pleistocene–Holocene transition. The amplitude of SHF variations is about 1.3% of the insolation changes amplitude. The increase of carbon dioxide concentrations lagged by 2–3 kyr from the SHF increase and occurred synchronously with GST changes.

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Wennrich, V., P. S. Minyuk, V. Borkhodoev, A. Francke, B. Ritter, N. R. Nowaczyk, M. A. Sauerbrey, J. Brigham-Grette et M. Melles. « Pliocene to Pleistocene climate and environmental history of Lake El'gygytgyn, Far East Russian Arctic, based on high-resolution inorganic geochemistry data ». Climate of the Past 10, n^o 4 (23 juillet 2014) : 1381–99. http://dx.doi.org/10.5194/cp-10-1381-2014.

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Abstract. The 3.6 Ma sediment record of Lake El'gygytgyn/NE Russia, Far East Russian Arctic, represents the longest continuous climate archive of the terrestrial Arctic. Its elemental composition as determined by X-ray fluorescence scanning exhibits significant changes since the mid-Pliocene caused by climate-driven variations in primary production, postdepositional diagenetic processes, and lake circulation as well as weathering processes in its catchment. During the mid- to late Pliocene, warmer and wetter climatic conditions are reflected by elevated Si / Ti ratios, indicating enhanced diatom production in the lake. Prior to 3.3 Ma, this signal is overprinted by intensified detrital input from the catchment, visible in maxima of clastic-related proxies, such as K. In addition, calcite formation in the early lake history points to enhanced Ca flux into the lake caused by intensified weathering in the catchment. A lack of calcite deposition after ca. 3.3 Ma is linked to the development of permafrost in the region triggered by cooling in the mid-Pliocene. After ca. 3.0 Ma the elemental data suggest a gradual transition to Pleistocene-style glacial–interglacial cyclicity. In the early Pleistocene, the cyclicity was first dominated by variations on the 41 kyr obliquity band but experienced a change to a 100 kyr eccentricity dominance during the middle Pleistocene transition (MPT) at ca. 1.2–0.6 Ma. This clearly demonstrates the sensitivity of the Lake El'gygytgyn record to orbital forcing. A successive decrease of the baseline levels of the redox-sensitive Mn / Fe ratio and magnetic susceptibility between 2.3 and 1.8 Ma reflects an overall change in the bottom-water oxygenation due to an intensified occurrence of pervasive glacial episodes in the early Pleistocene. The coincidence with major changes in the North Pacific and Bering Sea paleoceanography at ca. 1.8 Ma implies that the change in lake hydrology was caused by a regional cooling in the North Pacific and the western Beringian landmass and/or changes in the continentality. Further increases in total organic carbon and total nitrogen content after ca. 1.6 Ma are attributed to reduced organic matter decay in the sediment during prolonged anoxic periods. This points to more extensive periods of perennial ice coverage, and thus, to a progressive shifts towards more intense peak glacial periods. In the course of the Pleistocene glacial–interglacial sequence eight so-called "super-interglacials" occur. Their exceptionally warm conditions are reflected by extreme Si / Ti peaks accompanied by lows in Ti, K, and Fe, thus indicating extraordinary high lake productivity.

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Liebrand, Diederik, et Anouk T. M. de Bakker. « Bispectra of climate cycles show how ice ages are fuelled ». Climate of the Past 15, n^o 6 (22 novembre 2019) : 1959–83. http://dx.doi.org/10.5194/cp-15-1959-2019.

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Abstract. The increasingly nonlinear response of the climate–cryosphere system to insolation forcing during the Pliocene and Pleistocene, as recorded in benthic foraminiferal stable oxygen isotope ratios (δ18O), is marked by a distinct evolution in ice-age cycle frequency, amplitude, phase, and geometry. To date, very few studies have thoroughly investigated the non-sinusoidal shape of these climate cycles, leaving precious information unused to further unravel the complex dynamics of the Earth's system. Here, we present higher-order spectral analyses of the LR04 δ18O stack that describe coupling and energy exchanges among astronomically paced climate cycles. These advanced bispectral computations show how energy is passed from precession-paced to obliquity-paced climate cycles during the Early Pleistocene (from ∼2500 to ∼750 ka) and ultimately to eccentricity-paced climate cycles during the Middle and Late Pleistocene (from ∼750 ka onward). They also show how energy is transferred among many periodicities that have no primary astronomical origin. We hypothesise that the change of obliquity-paced climate cycles during the mid-Pleistocene transition (from ∼1200 to ∼600 ka), from being a net sink into a net source of energy, is indicative of the passing of a land-ice mass loading threshold in the Northern Hemisphere (NH), after which cycles of crustal depression and rebound started to resonate with the ∼110 kyr eccentricity modulation of precession. However, precession-paced climate cycles remain persistent energy providers throughout the Late Pliocene and Pleistocene, which is supportive of a dominant and continuous fuelling of the NH ice ages by insolation in the (sub)tropical zones, and the control it exerts on meridional heat and moisture transport through atmospheric and oceanic circulation.

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Ghinassi, Massimiliano, Oriol Oms, Mauro Papini, Fabio Scarciglia, Giorgio Carnevale, Federico Sani, Lorenzo Rook et al. « An integrated study of the Homo -bearing Aalat stratigraphic section (Eritrea) : An expanded continental record at the Early–Middle Pleistocene transition ». Journal of African Earth Sciences 112 (décembre 2015) : 163–85. http://dx.doi.org/10.1016/j.jafrearsci.2015.09.012.

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Djamali, Morteza, Jacques-Louis de Beaulieu, Madjid Shah-hosseini, Valérie Andrieu-Ponel, Philippe Ponel, Abdolhossein Amini, Hossein Akhani et al. « A late Pleistocene long pollen record from Lake Urmia, Nw Iran ». Quaternary Research 69, n^o 03 (mai 2008) : 413–20. http://dx.doi.org/10.1016/j.yqres.2008.03.004.

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A palynological study based on two 100-m long cores from Lake Urmia in northwestern Iran provides a vegetation record spanning 200 ka, the longest pollen record for the continental interior of the Near East. During both penultimate and last glaciations, a steppe ofArtemisiaand Poaceae dominated the upland vegetation with a high proportion of Chenopodiaceae in both upland and lowland saline ecosystems. WhileJuniperusand deciduousQuercustrees were extremely rare and restricted to some refugia,Hippophaë rhamnoidesconstituted an important phanerophyte, particularly during the late last glacial period. A pronounced expansion inEphedrashrub-steppe occurred at the end of the penultimate late-glacial period but was followed by extreme aridity that favoured anArtemisiasteppe. Very high lake levels, registered by both pollen and sedimentary markers, occurred during the middle of the last glaciation and late part of the penultimate glaciation. The late-glacial to early Holocene transition is represented by a succession ofHippophaë, Ephedra, Betula, Pistaciaand finallyJuniperusandQuercus. The last interglacial period (Eemian), slightly warmer and moister than the Holocene, was followed by two interstadial phases similar in pattern to those recorded in the marine isotope record and southern European pollen sequences.

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Demezhko, D. Y., et A. A. Gornostaeva. « Late Pleistocene–Holocene ground surface heat flux changes reconstructed from borehole temperature data (the Urals, Russia) ». Climate of the Past 11, n^o 4 (9 avril 2015) : 647–52. http://dx.doi.org/10.5194/cp-11-647-2015.

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Abstract. We use geothermal reconstruction of the ground surface temperature (GST) history early obtained in the Middle Urals to determine the surface heat flux (SHF) history over the past 35 kyr. A new algorithm of GST–SHF transformation was applied to solve this problem. The timescale of geothermal reconstructions has been corrected by comparing the estimated heat flux and annual insolation at the latitude of 60° N. The consistency of SHF and insolation changes on the interval 35–6 kyr BP with the linear correlation coefficient R = 0.99 points to orbital factors as the main cause of climatic changes during the Pleistocene–Holocene transition. The amplitude of SHF variations is about 1.3% of the insolation change amplitude. The increase of carbon dioxide concentrations lagged by 2–3 kyr from the SHF increase and occurred synchronously with GST changes.

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Aswan, Aswan. « Geological stories from the journey of mollusks fossils in Java ». Berita Sedimentologi 47, n^o 3 (28 décembre 2021) : 73–74. http://dx.doi.org/10.51835/bsed.2021.47.3.361.

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The journey began in the Eocene with the presence of mollusk fossil in the Nanggulan Formation (near Yogyakarta) in Central Java. Many experts believe this was the early part of the Tethys system which might still be connected to the Tethys system in Europe.The oldest mollusk fossils type locality after Nanggulan is the Early Miocene Jonggrangan Formation in Kulon Progo near the city of Yogyakarta, which is dominated by the gastropod Haustator specimen. Molluscan paleontological studies of this type of locality reflect a restricted environment with less influence of the Tethyan system. Haustator are considered as the ancestor of the Turritellidae group, which is found mostly on Java Island, during the younger Tertiary to Quaternary Periods.The story continued to the Middle Miocene where the Tethyan realms indication was clearly observed by the presence of some typical Tethys species such as Volema and Babylonia from Nyalindung Formation, West Java. The regional sea level rise in this epoch (around 12 Ma) that was indicated by the presence of Vicarya as an index fossil, which occurrence was due to land submerging to become mangroves area. The fossil then quickly become extinct when the sea level dropped back.Late Miocene to Pliocene was like the transition period from the Tethyan realm to the Pacific realm, where the Tethyan fauna was no longer present. Only evolutional traces of the Middle Miocene mollusk fossils were observed. This continuous evolution is most clearly seen in Turritella cramatensis (late Miocene), Turritella acuticarinata (early Pliocene) and Turritella cikumpaiensis (late Pliocene) which was interpreted to have originated from Turritella angulata as their ancestors.Earth cooling environment that happened in the late Pliocene/early Pleistocene has led the diversity and evolution of a new group of mollusks, most clearly observed from the abundance of Turritella bantamensis in the Bojong Formation, Banten. The new Turritella group has a curved whorl that different from its predecessor with an angled whorl shape.Plio-Pleistocene tectonics event has ended the period of Java marine mollusks domination, then only freshwater mollusk fossils can be found in almost all Quaternary mollusks-bearing deposits.

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Quillévéré, Frédéric, Nadège Nouailhat, Sébastien Joannin, Jean-Jacques Cornée, Pierre Moissette, Christophe Lécuyer, François Fourel, Konstantina Agiadi, Efterpi Koskeridou et Gilles Escarguel. « An onshore bathyal record of tectonics and climate cycles at the onset of the Early-Middle Pleistocene Transition in the eastern Mediterranean ». Quaternary Science Reviews 209 (avril 2019) : 23–39. http://dx.doi.org/10.1016/j.quascirev.2019.02.012.

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McHenry, Lindsay J., Jackson K. Njau, Ignacio de la Torre et Michael C. Pante. « Geochemical “fingerprints” for Olduvai Gorge Bed II tuffs and implications for the Oldowan–Acheulean transition ». Quaternary Research 85, n^o 1 (janvier 2016) : 147–58. http://dx.doi.org/10.1016/j.yqres.2015.10.005.

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Bed II is a critical part of early Pleistocene Olduvai Gorge, Tanzania. Its deposits include transitions from humid to more arid conditions (with associated faunal changes), from Homo habilis to erectus, and from Oldowan to Acheulean technology. Bed II (~ 1.8–1.2 Ma) is stratigraphically and environmentally complex, with facies changes, faulting, and unconformities, making site-to-site correlation over the ~ 20 km of exposure difficult. Bed II tuffs are thinner, less evenly preserved, and more reworked than those of Bed I. Five marker tuffs (Tuffs IIA–IID, Bird Print Tuff (BPT)), plus local tephra, were collected from multiple sites and characterized using stratigraphic position, mineral assemblage, and electron probe microanalysis of phenocryst (feldspar, hornblende, augite, titanomagnetite) and glass (where available) composition. Lowermost Bed II tuffs are dominantly nephelinitic, Middle Bed II tuffs (BPT, Tuff IIC) have basaltic components, and upper Bed II Tuff IID is trachytic. The BPT and Tuff IID are identified widely using phenocryst compositions (high-Ca plagioclase and high-Ti hornblende, respectively), though IID was originally (Hay, 1976) misidentified as Tuff IIC at Loc 91 (SHK Annexe) in the Side Gorge. This work helps establish a high-resolution basin-wide paleolandscape context for the Oldowan–Acheulean transition and helps link hominin, faunal and archaeological records.

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Shemer, Maayan, Onn Crouvi, Ron Shaar, Yael Ebert, Ari Matmon, Liora Kolska Horwitz, Véra Eisenmann, Yehouda Enzel et Omry Barzilai. « Geochronology, paleogeography, and archaeology of the Acheulian locality of ‘Evron Landfill in the western Galilee, Israel ». Quaternary Research 91, n^o 2 (27 décembre 2018) : 729–50. http://dx.doi.org/10.1017/qua.2018.107.

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AbstractA multidisciplinary study was conducted in a newly discovered Paleolithic locality, named ‘Evron Landfill. This locality is a part of the Lower Paleolithic complex of ‘Evron located at the western Galilee, Israel. Examination of artifacts has enabled the cultural attribution of ‘Evron Landfill to the Early Acheulian, while detailed paleomagnetic stratigraphy places the hominin occupations near the Brunhes–Matuyama transition ~0.77 Ma. This age is constrained by cosmogenic isotope burial dating of the sediments overlying the Paleolithic finds, providing a minimum age of ~0.66±0.11 Ma for hominin activity at the site. These results are further supported by the biochronological information derived from the faunal assemblage. Comparative analyses of faunal remains and lithic artifacts from ‘Evron Landfill demonstrate similarities to the assemblages from the Early Acheulian site of Evron Quarry, located ~300 m to the south. Pedo-sedimentological analyses indicate that hominin activity took place in a marsh environment in proximity to the Mediterranean coast, which probably fluctuated in both space and time with a fluvial environment. In addition, this study provides important data about ancient coastal activity during the early to middle Pleistocene.

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Blain, Hugues-Alexandre, et Salvador Bailon. « Extirpation of Ophisaurus (Anguimorpha, Anguidae) in Western Europe in the context of the disappearance of subtropical ecosystems at the Early-Middle Pleistocene transition ». Palaeogeography, Palaeoclimatology, Palaeoecology 520 (avril 2019) : 96–113. http://dx.doi.org/10.1016/j.palaeo.2019.01.023.

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Vandorpe, T., C. Wienberg, D. Hebbeln, M. Van den Berghe, S. Gaide, P. Wintersteller et D. Van Rooij. « Multiple generations of buried cold-water coral mounds since the Early-Middle Pleistocene Transition in the Atlantic Moroccan Coral Province, southern Gulf of Cádiz ». Palaeogeography, Palaeoclimatology, Palaeoecology 485 (novembre 2017) : 293–304. http://dx.doi.org/10.1016/j.palaeo.2017.06.021.

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Wang, Bin, Kanto Nishikawa, Masafumi Matsui, Truong Quang Nguyen, Feng Xie, Cheng Li, Janak Raj Khatiwada et al. « Phylogenetic surveys on the newt genus Tylototriton sensu lato (Salamandridae, Caudata) reveal cryptic diversity and novel diversification promoted by historical climatic shifts ». PeerJ 6 (12 mars 2018) : e4384. http://dx.doi.org/10.7717/peerj.4384.

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Résumé :

Global climatic transitions and Tibetan Plateau uplifts are hypothesized to have profoundly impacted biodiversity in southeastern Asia. To further test the hypotheses related to the impacts of these incidents, we investigated the diversification patterns of the newt genus Tylototriton sensu lato, distributed across the mountain ranges of southeastern Asia. Gene-tree and species-tree analyses of two mitochondrial genes and two nuclear genes revealed five major clades in the genus, and suggested several cryptic species. Dating estimates suggested that the genus originated in the early-to-middle Miocene. Under different species delimitating scenarios, diversification analyses with birth-death likelihood tests indicated that the genus held a higher diversification rate in the late Miocene-to-Pliocene era than that in the Pleistocene. Ancestral area reconstructions indicated that the genus originated from the northern Indochina Peninsula. Accordingly, we hypothesized that the Miocene Climatic Transition triggered the diversification of the genus, and the reinforcement of East Asian monsoons associated with the stepwise uplifts of the Tibetan Plateau promoted the radiation of the genus in southeastern Asia during the Miocene-to-Pliocene period. Quaternary glacial cycles likely had limited effects on speciation events in the genus, but mainly had contributions on their intraspecific differentiations.

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Articles de revues sur le sujet « Early-Middle Pleistocene Transition »

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