Articles de revues : « Early Middle Pleistocene »

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Rodríguez-Gómez, Guillermo, Jesús Rodríguez, Jesús A. Martín-González et Ana Mateos. « Evaluating the impact of Homo-carnivore competition in European human settlements during the early to middle Pleistocene ». Quaternary Research 88, n^o 1 (24 mai 2017) : 129–51. http://dx.doi.org/10.1017/qua.2017.20.

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AbstractFossil remains and the technological complexes recorded in archaeological sites suggest that the human presence in Europe late in the early and middle Pleistocene was discontinuous. Moreover, competition for meat with other secondary consumers could have delayed the human dispersal through Europe. However, evaluation of the extent competition intensity among secondary consumers suggests this influenced the discontinuity of the human settlement of Europe between 1.1 and 0.2 Ma. Using a mathematical model, we estimate the amount of biomass available in a community for secondary consumers. The amount of available biomass is subsequently distributed among the guild of secondary consumers according to their requirements and prey preferences. Indexes that quantify the competition intensity among secondary consumers to compare the conditions in different paleoecosystems show that the competition intensity late in the early Pleistocene, early in the middle Pleistocene, and late in the middle Pleistocene does not support the view that an increase in competition intensity constrained the expansion of human populations early in the middle Pleistocene. Somewhat paradoxically, the lowest competition intensity is estimated to have occurred early in the middle Pleistocene, most likely because of an increase in the number of large herbivore species and a decrease in the number of secondary consumers. The early Pleistocene paleoecosystems supported higher competition intensity than the middle Pleistocene ecosystems, likely because of the different configuration in the food webs of these two periods (the early and middle Pleistocene).

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Pečnerová, Patrícia, David Díez-del-Molino, Tom van der Valk, Marianne Dehasque, Anders Götherström et Love Dalén. « Mammuthus sp. (Early and Middle Pleistocene Mammoths) ». Trends in Genetics 37, n^o 7 (juillet 2021) : 682–83. http://dx.doi.org/10.1016/j.tig.2021.04.006.

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Tchernov, Eitan, et Evangelia Tsoukala. « Middle Pleistocene (Early Toringian) Carnivore Remains from Northern Israel ». Quaternary Research 48, n^o 1 (juillet 1997) : 122–36. http://dx.doi.org/10.1006/qres.1997.1901.

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Seventy well-preserved fossil remains from deposits of an eroded karstic cave in the Upper Galilee of northern Israel includeUrsus deningeri(Ursidae),Canis lupus cf.mosbachensis (Canidae),Crocuta crocuta cf. praespelaea (Hyaenidae), Panthera leo cf. spelaea (Felidae), and Dama sp. (Cervidae). This assemblage probably dates to the Early Toringian (MQ2, Middle Pleistocene). Ursus deningeri and Panthera leo cf. spelaeahave never before been recorded south of the Taurus–Zagros mountain chain. We correlate the carnivore faunule with some Near Eastern and southern Levantine sites and assume that only a severe cold phase could have shifted these species over the Taurus–Zagros mountain chain this far to the south. Due to the relative scarcity of Middle Pleistocene assemblages, especially carnivores, in the southern Levant, the biogeographic connection between the southern Levant and the Near East is still not well known. This faunule elucidates Pleistocene biotic exchanges between Europe and the Levant during this period.

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HALL, Adrian M., Jon W. MERRITT, E. Rodger CONNELL et Alun HUBBARD. « Early and Middle Pleistocene environments, landforms and sediments in Scotland ». Earth and Environmental Science Transactions of the Royal Society of Edinburgh 110, n^o 1-2 (4 octobre 2018) : 5–37. http://dx.doi.org/10.1017/s1755691018000713.

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ABSTRACTThis paper reviews the changing environments, developing landforms and terrestrial stratigraphy during the Early and Middle Pleistocene stages in Scotland. Cold stages after 2.7 Ma brought mountain ice caps and lowland permafrost, but larger ice sheets were short-lived. The late Early and Middle Pleistocene sedimentary record found offshore indicates more than 10 advances of ice sheets from Scotland into the North Sea but only 4–5 advances have been identified from the terrestrial stratigraphy. Two primary modes of glaciation, mountain ice cap and full ice sheet modes, can be recognised. Different zones of glacial erosion in Scotland reflect this bimodal glaciation and the spatially and temporally variable dynamics at glacier beds. Depths of glacial erosion vary from almost zero in Buchan to hundreds of metres in glens in the western Highlands and in basins both onshore and offshore. The presence of tors and blockfields indicates repeated development of patches of cold-based, non-erosive glacier ice on summits and plateaux. In lowlands, chemical weathering continued to operate during interglacials, but gruss-type saprolites are mainly of Pliocene to Early Pleistocene age. The Middle Pleistocene terrestrial stratigraphic record in Scotland, whilst fragmentary and poorly dated, provides important and accessible evidence of changing glacial, periglacial and interglacial environments over at least three stadial–interstadial–interglacial cycles. The distributions of blockfields and tors and the erratic contents of glacial sediments indicate that the configuration, thermal regime and pattern of ice flow during MIS 6 were broadly comparable to those of the last ice sheet. Improved control over the ages of Early and Middle Pleistocene sediments, soils and saprolites and on long-term rates of weathering and erosion, combined with information on palaeoenvironments, ice extent and sea level, will in future allow development and testing of new models of Pleistocene tectonics, isostasy, sea-level change and ice sheet dynamics in Scotland.

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Whiteman, Colin A., et James Rose. « Early-Middle Pleistocene Beheading of the River Thames ». Paléoréseaux hydrographiques quaternaires : centenaire W.M. Davis 51, n^o 3 (30 novembre 2007) : 327–36. http://dx.doi.org/10.7202/033131ar.

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ABSTRACT This paper marks the centenary of the first of three articles by W.M. Davis on the beheading of the Thames, beginning with a statement of his capture hypothesis in 1895 and concluding with attempts to explain anomalous misfit streams in 1899 and 1909. It discusses Davis's classic thesis of river capture by slow, long-term landscape evolution and his apparent reluctance to accept the fact of rapid Quaternary climate change. In contrast, recent work based on lithostratigraphy, biostratigraphy and morphostratigraphy emphasises the dynamism of the Quaternary Period and its influence on river capture. Possible mechanisms for the beheading of the Thames, tectonism, glacial erosion and conventional Davisian river capture, and the timing of the event, are discussed. In conclusion, the paper summarises known and unknown components of the problem of the beheading of the Thames, and discusses the extent of Davis's influence on later Thames studies.

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Belshaw, R. K., P. L. Gibbard, J. B. Murton et D. K. Murton. « Early Middle Pleistocene drainage in southern central England ». Netherlands Journal of Geosciences - Geologie en Mijnbouw 93, n^o 4 (12 septembre 2014) : 135–45. http://dx.doi.org/10.1017/njg.2014.25.

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AbstractThe fluvial sequences of the Milton and the Letchworth formations in the south Midlands of England and neighbouring regions represent at least two pre-existing rivers, the Milton and Brigstock streams, underlying Middle Pleistocene glacial sediments. The Milton Formation includes sand sourced from the Midlands bedrock. This implies that both streams were aligned in a northwest to southeast direction. This direction parallels the contemporaneous courses of the rivers Thames and Trent, the former turning towards the east and northeast to enter the North Sea. Their alignments indicate that the Milton and Letchworth streams formed left-bank tributaries of the Thames, joining the river in Hertfordshire and Essex, as illustrated in the article. This reconstruction has important implications for the interpretation of the proto-Soar river of the south Midlands, represented by the Baginton Formation. Although originally thought to represent a late Middle Pleistocene line, this southwest to northeast aligned system was reinterpreted as the headwaters of a pre-Anglian ‘Bytham river’, a1ligned towards East Anglia. However, recent work has shown that this river could not have existed in the pre-Anglian since there is no link between the Midlands and East Anglian spreads. Recent re-recognition that the Baginton Formation deposits do represent a later, post-Anglian drainage line is reinforced by the identification of the Milton and Letchworth streams, whose catchments occupied the area later drained by the proto-Soar. Overall, the main drainage alignment in southern England during the pre-Anglian period was dominated by northwest–southeast-draining consequent rivers adjusted to the regional geological dip. After widespread drainage disruption caused by the Anglian glaciation, northeast–southwest-orientated subsequent streams eroded frost-susceptible clay bedrock under periglacial and permafrost conditions, and beheaded the courses of some of the older consequent streams.

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Rose, James. « Early and Middle Pleistocene landscapes of eastern England ». Proceedings of the Geologists' Association 120, n^o 1 (janvier 2009) : 3–33. http://dx.doi.org/10.1016/j.pgeola.2009.05.003.

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Jianhua, Jin, et Liao Wenbo. « Palaeovegetation and palaeoclimate during middle Late Palaeolithic age of Lingnan area, China ». Journal of Palaeosciences 57, n^o (1-3) (31 décembre 2008) : 511–14. http://dx.doi.org/10.54991/jop.2008.269.

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The fossil spore-pollen recovered from middle Late Palaeolithic age (i.e. late Middle Pleistocene to Late Pleistocene) of Lingnan area of China are mainly distributed in the Pearl River Mouth Basin, Pearl River Delta, Shenzhen, Zhanjiang, Leizhou Peninsula and Hainan Island. As revealed by the fossil spore-pollen, the vegetation of Lingnan area during the late Middle Pleistocene to Late Pleistocene comprised mainly of subtropical evergreen broad-leaved forest, evergreen and deciduous broad-leaved mixed forest, and coniferous forest. During the early Late Pleistocene, the area experienced transgression of sea, and climate became hot leading to the development, of mangrove vegetation in the littoral area. On recession of sea, near the end of Late Pleistocene, climate became cooler and drier and the mangrove forest diminished significantly. Thus, the above mentioned luxuriant vegetation and subtropical climate in middle Late palaeolithic age suggests existence of favourable conditions for early Homo sapiens activities in the Lingnan area.

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Schick, Kathy, et Nicholas Toth. « Acheulean Industries of the Early and Middle Pleistocene, Middle Awash, Ethiopia ». L'Anthropologie 121, n^o 5 (novembre 2017) : 451–91. http://dx.doi.org/10.1016/j.anthro.2017.10.009.

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Liu, Chao, Qiyun Lei, Peng Du, Zhiqun Wu, Zeshan Li, Sihan Yu, Shun Yang et Yin Wang. « Activity Characteristic of the Two Buried Faults in Zhongwei Basin along the Northeastern Margins of Tibetan Plateau, China, by Means of Shallow Seismic and Composite Drilling Section Exploration ». Applied Sciences 12, n^o 23 (25 novembre 2022) : 12074. http://dx.doi.org/10.3390/app122312074.

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By using shallow seismic exploration, composite drilling section exploration and sample dating test, we have obtained precise positions, burial depths of uppermost point and activity characteristics of Hetan-Guotan buried fault and Zhenjing-Zhenbei buried fault in Zhongwei Basin. The results show that the latest active period of Hetan-Guotan buried fault is the middle-late Middle Pleistocene, and the latest active period of Zhenjing-Zhenbei buried fault is the Early and Middle Pleistocene. The two buried faults became inactive at the end of the Middle Pleistocene and have been inactive since the Late Pleistocene.

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Markova, A. K., et A. Yu Puzachenko. « MIDDLE PLEISTOCENE SMALL MAMMAL fAUNAS Of EUROPE : EVOLUTION, BIOSTRATIGRAPHY, CORRELATIONS ». GEOGRAPHY, ENVIRONMENT, SUSTAINABILITY 11, n^o 3 (29 septembre 2018) : 21–38. http://dx.doi.org/10.24057/2071-9388-2018-11-3-21-38.

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The paper is concerned with the small mammal fauna evolution in Europe in the Middle Pleistocene. The information on the faunas of the end of the Early Pleistocene has been also taken into consideration. The data available made possible identifying several stages in the small mammal evolution. Not all intervals within the Middle Pleistocene are provided with sufficient information for recognizing individual stages; that is particularly true for the cold periods of the Middle Pleistocene – the Donian and the Okian glaciations (=Elsterian, =Anglian). Based on the studies of small mammal localities, the biostratigraphic scheme has been developed, the principal phylogenetic lineages of Arvicolinae were traced, and maps of the Middle Pleistocene small mammal localities have been compiled

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van Kolfschoten, Thijs, et Philip L. Gibbard. « The Eemian - local sequences, global perspectives : introduction ». Netherlands Journal of Geosciences 79, n^o 2-3 (août 2000) : 129–33. http://dx.doi.org/10.1017/s0016774600021661.

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The history of this volume goes back to a 1973 INQUA congress in New Zealand, where an INQUA Commission of Stratigraphy working group on major subdivisions of the Pleistocene was established. The Pleistocene series/epoch was hitherto generally subdivided into the Lower/Early, Middle and Upper/Late Pleistocene (see, among others, Zeuner, 1935, 1959) but the boundaries between these subseries/subepochs were not formally defined. The boundary between the Early and Middle Pleistocene was, in the European literature, put at the base of the Cromerian Complex (Zagwijn, 1963) or at the Brunhes/Matuyama magnetic boundary (Richmond, 1996).

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Cramb, Jonathan, Gilbert J. Price et Scott A. Hocknull. « Short-tailed mice with a long fossil record : the genusLeggadina(Rodentia : Muridae) from the Quaternary of Queensland, Australia ». PeerJ 6 (21 septembre 2018) : e5639. http://dx.doi.org/10.7717/peerj.5639.

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The genusLeggadina(colloquially known as ‘short-tailed mice’) is a common component of Quaternary faunas of northeastern Australia. They represent a member of the Australian old endemic murid radiation that arrived on the continent sometime during the late Cenozoic. Here we describe two new species of extinctLeggadinafrom Quaternary cave deposits as well as additional material of the extinctLeggadina macrodonta.Leggadina irvinisp. nov. recovered from Middle-Upper (late) Pleistocene cave deposits near Chillagoe, northeastern Queensland, is the biggest member of the genus, being substantially larger than any other species so far described.Leggadina webbisp. nov. from Middle Pleistocene cave deposits at Mount Etna, central eastern Queensland, shares features with the oldest species of the genus, the Early PleistoceneL. gregoriensis. Based on the current palaeoecological interpretation of the type locality,L. webbi, represents the only member of the genus that inhabited rainforest. The succession ofLeggadinaspecies through the late Quaternary suggests an ecological replacement of the extinct large-bodiedL. irviniwith the extant, small-bodiedL. lakedownesisat Chillagoe. At Mt. Etna, the extinct rainforest speciesL. webbiis replaced with the extant xeric-adaptedL. forrestiduring the latest Middle Pleistocene. This replacement is associated with a mid-Pleistocene shift towards progressive intensifying seasonal and arid climates. Our study adds to the growing list of small-bodied faunal extinctions during the late Quaternary of northern Australia.

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Alberdi, María Teresa, et Maria Rita Palombo. « The late Early to early Middle Pleistocene stenonoid horses from Italy ». Quaternary International 288 (mars 2013) : 25–44. http://dx.doi.org/10.1016/j.quaint.2011.12.005.

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Agadzhanyan, Alexandre K., Inesa A. Vislobokova, Mikhail V. Shunkov et V. A. Ulyanov. « Pleistocene mammal fauna of the Trlica locality, Montenegro ». Fossil Imprint 73, n^o 1-2 (15 août 2017) : 93–114. http://dx.doi.org/10.2478/if-2017-0005.

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The paper presents new evidence on the small and large mammal fauna from the Trlica locality, Montenegro, based on our records from the 2010 – 2014 excavations. It is shown that the lower layers of the locality correspond to the Early Pleistocene, and the upper layers are dated as the beginning of the Middle Pleistocene. The results obtained allow us to characterize the environment in which the oldest hominid migrants dwelt in this region of South-Eastern Europe. Within the interval 1.8–1.5 Ma, there was a relatively cool climate in the region. At the beginning of the Middle Pleistocene, the climate became milder; the areas occupied by forests, including broad-leaved forests, increased. The presence of Lagurini throughout the section is evidence of the existence of local areas of steppe in northern Montenegro during the Early Pleistocene and first half of the Middle Pleistocene.

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Pedersen, Anette Mønsted. « Pliocene - Middle Pleistocene biostratigraphy in the Central Danish North Sea wells E-1, P-1 and TWB-12 ». Danmarks Geologiske Undersøgelse Serie C 13 (31 décembre 1995) : 1–28. http://dx.doi.org/10.34194/seriec.v13.7117.

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Six foraminiferal assemblage zones and 6 subzones have been identified in the boreholes TWB-12, P-1 and E-1. The zones cover the interval from the Pliocene to the Middle Pleistocene. In TWB-12 and E-1 the Pliocene /Pleistocene boundary is placed at the first common occurrence of the species Elphidium oregonense. This species was not found in P-1, and the boundary is here, tentatively, placed above the last local occurrence of Cibicides grossus. The palaeoecological variations indicated by the Pleistocene assemblages, suggest several oscillations both in water depth and in palaeotemperature. A cold, shallow water interval with Elphidium oregonense at the Pliocene/Pleistocene boundary is followed by a Early Pleistocene warm, deep water interval with a high content of the genera Stainforthia and Bulimina. These deposits are probably from the warm Tiglian stage. The succeeding Early Pleistocene fauna! assemblages indicate a cold, upwards shallowing environment, and in this interval the arctic species Elphidiella gorbunovi often has a short ranged occurrence. The fauna! assemblages of the overlying deposits are characterized by the species Elphidium ustulatum and Elphidium albiumbilicatum, and indicates nearshore/ deltaic conditions. This part of the sequence probably includes the Early /Middle Pleistocene boundary. The uppermost assemblages in the examined sequence indicate arctic, shallow water conditions. They are, probably, of Saalian age, and are referred to Middle Pleistocene.

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Lin, Jingxing, Shanlin Zhang, Jinbo Qiu, Biaoyun Wu, Huanzhong Huang, Huizhen Huang, Jianguo Xi, Baogen Tang, Zuren Cai et Yubao He. « Quaternary Marine Transgressions and Paleoclimate in the Yangtze River Delta Region ». Quaternary Research 32, n^o 3 (novembre 1989) : 296–306. http://dx.doi.org/10.1016/0033-5894(89)90096-3.

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AbstractEight marine transgressions have been recognized from more than 30 deep drill holes (ca. 300 m deep) through Quaternary sequences in the Yangtze River delta region. These are, in ascending order, the Rugao and Zhoupe transgressions (early Pleistocene); the Shanghai, Jiading, and Wangdian transgressions in the middle Pleistocene; the Jiangyin and Gehu transgressions in the late Pleistocene; and the Zhenjiang transgression in the Holocene. The transgressions correspond to warm periods and regressions to cold periods. The younger transgressions were not only of shorter duartion, but also of larger magnitude. The findings verify that there were five moderately warm periods during the early to middle Pleistocene and two very warm periods during the late Pleistocene in the Yangtze River delta region.

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Pandolfi, Luca, Carmelo Petronio et Leonardo Salari. « Bos primigenius Bojanus, 1827 from the Early Late Pleistocene Deposit of Avetrana (Southern Italy) and the Variation in Size of the Species in Southern Europe : Preliminary Report ». Journal of Geological Research 2011 (22 juin 2011) : 1–11. http://dx.doi.org/10.1155/2011/245408.

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Very abundant remains of Bos primigenius have been recovered in the early Late Pleistocene site of Avetrana (southern Italy). The site is characterized by a karst filling originated from a series of almost coeval depositional events. This discovery represents a rare record in the early Late Pleistocene of southern Europe. Biometrical analysis of the metapodial bones of aurochs from Avetrana gave the cue to examine the evolutive trend of the species in southern Europe, from the Middle Pleistocene to Holocene. This trend is characterized by an increase in size of the metapodial bones from Middle Pleistocene to early Late Pleistocene and to a decrease in size of the same during the late Late Pleistocene and Holocene. Also, the variations in size are competed by change in shape of the metapodial bones. These variations seem to be related with climatic fluctuations and competitions with Homo and Bison. At least, five evolutive stages are recognized; they constitute an important tool for the biochronological correlations among the Pleistocene sites of southern Europe.

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Kostopoulos, D. S., et G. D. Koufos. « SIMILARITY RELATIONSHIPS AMONG GREEK MIDDLE MIOCENE TO EARLY - MIDDLE PLEISTOCENE MAMMAL ASSEMBLAGES ». Bulletin of the Geological Society of Greece 40, n^o 1 (8 juin 2018) : 134. http://dx.doi.org/10.12681/bgsg.16498.

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The Greek fossil record of small and large mammal Local Faunal Assemblages is studied and compared by means of cluster analysis techniques using Jaccard similarity index and unweighted pair-group method. The analysis allow recognizing a good arrangement of the Greek LFAs according to time and a main cluster gap, corresponding to an important faunal renewal that, however, is not synchronous in the large and small mammal community. Minor groupings of large mammal faunas seem also to fit with main climatic trends, whereas the small mammal assemblage appears to undergo longer periods oftaxonomic stability

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Choiriah, Siti U., Carolus Prasetyadi, Dwi F. Yudiantoro, Rubiyanto Kapid et Nanda A. Nurwantari. « Pliocene-Pleistocene Calcareous Nannoplankton Biostratigraphy, Section Banyuurip, Rembang Zone, East Java Basin, Indonesia ». International Journal of Geology and Earth Sciences 6, n^o 4 (décembre 2020) : 44–49. http://dx.doi.org/10.18178/ijges.6.4.44-49.

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The present study was carried out at the Banyuurip area in the East Java Basin, Indonesia, a site contains nannofossil assemblages of Pliocene to Pleistocene, with lithology is suitable for nannoplankton research. Methods used in this research include making a Stratigraphical section Measurement, collecting 41 samples and preparing the samples with the smear slides method to be observed using a polarizing microscope with 1000x magnification, and preparing several rock samples using SEM analysis. Analysis of nannofossil resulted in identifying 19 genus and 51 species. Biostratigraphic zone of this study can be arranged into 9 biostratigraphic zones. The zone order from older to younger are: a) Sphenolithus neoabies Zone /NN12/Late Miocene to Early Pliocene, b) Ceratolithus rugosus Zone /NN13/Early Pliocene, c) Discoaster asymmetricus–Reticulofenestra pseudoumbulicus Range Zone/NN14-NN15/Early Pliocene to Middle Pliocene, d) Discoaster surculus Zone/NN16/Middle Pliocene, e) Discoaster pentaradiatus Zone/NN17/Late Pliocene, f) Discoaster brouweri Zone/NN18/Late Pliocene, g) Gephyrocapsa caribbeanica Zone/NN19 Zone/Early Pleistocene, h) Gephyrocapsa oceanica Zone/NN20 Zone/Middle Pleistocene, and i) Emiliania huxleyi Zone/NN21 Zone/Late Pleistocene.

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Tesakov, A. S. « Early Middle Pleistocene Ellobius (Rodentia, Cricetidae, Arvicolinae) from Armenia ». Russian Journal of Theriology 15, n^o 2 (29 novembre 2016) : 151–58. http://dx.doi.org/10.15298/rusjtheriol.15.2.07.

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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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Hosfield, Robert. « The British Lower Palaeolithic of the early Middle Pleistocene ». Quaternary Science Reviews 30, n^o 11-12 (juin 2011) : 1486–510. http://dx.doi.org/10.1016/j.quascirev.2010.02.026.

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Head, Martin J., et Philip L. Gibbard. « Early–Middle Pleistocene transitions : Linking terrestrial and marine realms ». Quaternary International 389 (décembre 2015) : 7–46. http://dx.doi.org/10.1016/j.quaint.2015.09.042.

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Geraads, Denis, Fethi Amani, Abdelouahed Ben-Ncer, Shannon P. McPherron, Jean-Paul Raynal et Jean-Jacques Hublin. « The rodents from the late middle Pleistocene hominid-bearing site of J'bel Irhoud, Morocco, and their chronological and paleoenvironmental implications ». Quaternary Research 80, n^o 3 (novembre 2013) : 552–61. http://dx.doi.org/10.1016/j.yqres.2013.08.003.

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The rodents from the late middle Pleistocene hominin-bearing locality of J'bel Irhoud include the following species: Meriones shawii, Gerbillus grandis, Dipodillus campestris, Paraethomys ras, Lemniscomys barbarus, Mus cf. spretus, and Eliomys sp. We consider M. shawii, a living species, as identical with the middle Pleistocene Meriones maghrebianus. The mouse differs from the domestic Mus musculus but does not clearly fit into Mus spretus, either. The rare G. grandis looks identical with the form from the middle Pleistocene of Thomas quarries, which may suggest a rather early age for Irhoud. This is in agreement with the occurrence of Paraethomys, a genus unknown in the upper Pleistocene of Morocco, but the absence of the arvicolid Ellobius suggests that the site is younger than other middle Pleistocene sites, Doukkala II, Sidi Abderrahmane D2, and Irhoud-Derbala-Virage. Paleoecological indicators, such as the taxonomic habitat spectrum, or the relative abundances of Gerbillinae and Murinae, suggest a less xeric environment than in many earlier and later sites. Diversity indices, comparable to those of other middle Pleistocene sites, point to similarly favorable conditions before the major climatic crisis close to the middle/upper Pleistocene boundary that drastically reduced rodent diversity in North Africa.

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Bednarik, Robert G. « Seafaring in the Pleistocene ». Cambridge Archaeological Journal 13, n^o 1 (avril 2003) : 41–66. http://dx.doi.org/10.1017/s0959774303000039.

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Archaeological data from Wallacea (Indonesia) and elsewhere are summarized to show that the history of seafaring begins in the Early Pleistocene, and that this human capability eventually led to Middle Palaeolithic ocean crossings in the general region of Australia. To understand better the technological magnitude of these many maritime accomplishments, a series of replicative experiments are described, and the theoretical conditions of these experiments are examined. The proposition is advanced that hominid cognitive and cultural evolution during the Middle and early Late Pleistocene have been severely misjudged. The navigational feats of Pleistocene seafarers confirm the cultural evidence of sophistication available from the study of palaeoart.With comments from Mike Morwood, Michael Rowland, Matthew Spriggs, Iain Davidson, Ursula Mania, and G.A. Clark and followed by a reply from the author.

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Gibbard, P. L., R. G. West, W. H. Zagwijn, P. S. Balson, A. W. Burger, B. M. Funnell, D. H. Jeffery et al. « Early and early Middle Pleistocene correlations in the Southern North Sea basin ». Quaternary Science Reviews 10, n^o 1 (janvier 1991) : 23–52. http://dx.doi.org/10.1016/0277-3791(91)90029-t.

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Barsky, Deborah, Joan Garcia, Kenneth Martínez, Robert Sala, Yossi Zaidner, Eudald Carbonell et Isidro Toro-Moyano. « Flake modification in European Early and Early–Middle Pleistocene stone tool assemblages ». Quaternary International 316 (décembre 2013) : 140–54. http://dx.doi.org/10.1016/j.quaint.2013.05.024.

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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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Stringer, Chris. « The origin and evolution of Homo sapiens ». Philosophical Transactions of the Royal Society B : Biological Sciences 371, n^o 1698 (5 juillet 2016) : 20150237. http://dx.doi.org/10.1098/rstb.2015.0237.

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If we restrict the use of Homo sapiens in the fossil record to specimens which share a significant number of derived features in the skeleton with extant H. sapiens , the origin of our species would be placed in the African late middle Pleistocene, based on fossils such as Omo Kibish 1, Herto 1 and 2, and the Levantine material from Skhul and Qafzeh. However, genetic data suggest that we and our sister species Homo neanderthalensis shared a last common ancestor in the middle Pleistocene approximately 400–700 ka, which is at least 200 000 years earlier than the species origin indicated from the fossils already mentioned. Thus, it is likely that the African fossil record will document early members of the sapiens lineage showing only some of the derived features of late members of the lineage. On that basis, I argue that human fossils such as those from Jebel Irhoud, Florisbad, Eliye Springs and Omo Kibish 2 do represent early members of the species, but variation across the African later middle Pleistocene/early Middle Stone Age fossils shows that there was not a simple linear progression towards later sapiens morphology, and there was chronological overlap between different ‘archaic’ and ‘modern’ morphs. Even in the late Pleistocene within and outside Africa, we find H. sapiens specimens which are clearly outside the range of Holocene members of the species, showing the complexity of recent human evolution. The impact on species recognition of late Pleistocene gene flow between the lineages of modern humans, Neanderthals and Denisovans is also discussed, and finally, I reconsider the nature of the middle Pleistocene ancestor of these lineages, based on recent morphological and genetic data. This article is part of the themed issue ‘Major transitions in human evolution’.

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Beu, Alan G. « Gradual Miocene to Pleistocene uplift of the Central American isthmus : Evidence from tropical American tonnoidean gastropods ». Journal of Paleontology 75, n^o 3 (mai 2001) : 706–20. http://dx.doi.org/10.1017/s0022336000039743.

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Tonnoidean gastropods have planktotrophic larval lives of up to a year and are widely dispersed in ocean currents; the larvae maintain genetic exchange between adult populations. They therefore are expected to respond rapidly to new geographic barriers by either extinction or speciation. Fossil tonnoideans on the opposite coast of the Americas from their present-day range demonstrate that larval transport still was possible through Central America at the time of deposition of the fossils. Early Miocene occurrences of Cypraecassis tenuis (now eastern Pacific) in the Caribbean probably indicate that constriction of the Central American seaway had commenced by Middle Miocene time. Pliocene larval transport through the seaway is demonstrated by Bursa rugosa (now eastern Pacific) in Caribbean Miocene-latest Pliocene/Early Pleistocene rocks; Crossata ventricosa (eastern Pacific) in late Pliocene rocks of Atlantic Panama; Distorsio clathrata (western Atlantic) in middle Pliocene rocks of Ecuador; Cymatium wiegmanni (eastern Pacific) in middle Pliocene rocks of Atlantic Costa Rica; Sconsia sublaevigata (western Atlantic) in Pliocene rocks of Darien, Pacific Panama; and Distorsio constricta (eastern Pacific) in latest Pliocene-Early Pleistocene rocks of Atlantic Costa Rica. Continued Early or middle Pleistocene connections are demonstrated by Cymatium cingulatum (now Atlantic) in the Armuelles Formation of Pacific Panama. Tonnoideans indicate that the Central American seaway began to be constricted after early Miocene time, and some larval transport through the seaway was possible throughout Pliocene time. Intermittent marine connections were maintained at least during late Pliocene to early Pleistocene interglacial periods of high sea-level, and alternated with a land bridge during glacial periods of low sea-level.

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MacPhail, MK, GJ Jordan et RS Hill. « Key Periods in the Evolution of the Flora and Vegetation in Western Tasmania .I. The Early-Middle Pleistocene ». Australian Journal of Botany 41, n^o 6 (1993) : 673. http://dx.doi.org/10.1071/bt9930673.

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The relatively simple flora and structure of Nothofagus cunninghamii cool temperate rainforest in Tasmania is widely accepted to be the result of repeated glaciation during the Pleistocene. Plant macrofossils, spores and pollen preserved at Regatta Point, western Tasmania, indicate that several gymnosperms and subcanopy angiosperms with warm temperate affinities had survived one to several episodes of cold, possibly glacial climates, before becoming extinct in the early to middle Pleistocene: Callitris/Actinostrobus, Dacrycarpus, Austromyrtus, Eucalyptus spathulata-type, Haloragodendron-type, Loranthaceae, Quintinia and Symplocos. These co-existed in Nothofagus-Lagarostroboss franklinii rainforest with a number of taxa that are now restricted to upper subalpine-alpine habitats in Tasmania, such as Astelia, Gunnera and Microcachrys. The community is difficult to interpret in terms of modem species and we propose that either extinct taxa are being concealed by essentially modern pollen morphologies, that ecological preferences have altered since the early-middle Pleistocene, or both. Patterns of extinctions in Tasmania (and New Zealand) suggest that Pleistocene climatic change at middle-high latitudes presented an environmental stress not previously experienced during the Cenozoic, perhaps through widespread periglacial conditions, but also provided ecological and evolutionary opportunities for rainforest species tolerant of a wide range of conditions experienced during the late Pleistocene.

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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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AMEEN, MUHAMMAD, ABDUL MAJID KHAN, MUHAMMAD TAHIR WASEEM, RANA MANZOOR AHMAD, MUHAMMAD IMRAN, AYESHA IQBAL et AMTUR RAFEH. « Were late Gomphotheres (Plio-Pleistocene) of the Siwaliks at more Stress as Compared to early Gomphotheres (middle to late Miocene) ? » Journal of Bioresource Management 7, n^o 4 (31 décembre 2020) : 117–30. http://dx.doi.org/10.35691/jbm.0202.0158.

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Gomphotheres existed in the Siwaliks from the middle Miocene (14.2Ma) to the middle Pleistocene (0.8Ma) and became extinct later on. In this paper, we tried to discuss the reasons of such extinction of gomphotheres in the lower Pleistocene time span by considering Linear Enamel Hypoplasia (LEH) among 114 isolated tooth samples to assess whether ecological changes correlate with the stress factor in gomphotheres. For this purpose, the Siwalik gomphotheres were divided into two Groups viz. early gomphotheres (middle Miocene to late Miocene) and late gomphotheres (Pliocene to middle Pleistocene). We presented the hypothesis, that as the gomphotheres are characterized by the brachydonty and relied on browsing for their feeding while inhabiting the semi forest land setting thus, expected to have higher stress in Plio-Pleistocene time span as vegetational change around ~6 Ma may have exerted stress on late gomphotheres. The results for the occurrence of frequency of LEH indicated severe ecological stress in late gomphotheres (33%). The significant differences were found (P < 0.05) among the early gomphotheres and late gomphotheres which can be correlated to the vegetational change from C3 to C4, higher aridity indices and intensified seasonality after the late Miocene vegetational shift which may have resulted in substantial faunal turnover, extinction and speciation. We assume that such palaeoecological changes forced a competition with more pronounced grazers like of family Elephantidae and Bovidae resulting in extinction of gomphotheres during the late Pleistocene in the Siwaliks of Pakistan.

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Griffing, Corinne Y., John J. Clague, Rene W. Barendregt, Bettina Ercolano, Hugo Corbella, Jorge Rabassa et Nicholas J. Roberts. « Early and Middle Pleistocene glaciation of the southern Patagonian plain ». Journal of South American Earth Sciences 114 (mars 2022) : 103687. http://dx.doi.org/10.1016/j.jsames.2021.103687.

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Nirei, Takashi, et Misao Hongo. « Pollen biostratigraphy of the Early-Middle Pleistocene in central Japan ». Quaternary Research (Daiyonki-Kenkyu) 57, n^o 5 (1 octobre 2018) : 143–55. http://dx.doi.org/10.4116/jaqua.57.143.

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Masini, Federico, Maria Rita Palombo et Roberto Rozzi. « A reappraisal of the Early to Middle Pleistocene Italian Bovidae ». Quaternary International 288 (mars 2013) : 45–62. http://dx.doi.org/10.1016/j.quaint.2012.03.026.

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Whiteman, Colin A., et James Rose. « Thames River sediments of the British Early and Middle Pleistocene ». Quaternary Science Reviews 11, n^o 3 (janvier 1992) : 363–75. http://dx.doi.org/10.1016/0277-3791(92)90007-u.

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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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Jordan, GI, et RS Hill. « Two new Banksia species from pleistocene sediments in western Tasmania ». Australian Systematic Botany 4, n^o 3 (1991) : 499. http://dx.doi.org/10.1071/sb9910499.

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Subtribe Banksiinae of the Proteaceae was diverse in Tasmania in the early and middle Tertiary, but is now restricted to two species, Banksia marginata and B. serrata. Rapid and extreme environmental changes during the Pleistocene are likely causes of the extinction of some Banksia species in Tasmania. Such extinctions may have been common in many taxonomic groups. The leaves and infructescences of Banksia kingii Jordan & Hill, sp. nov. are described from late Pleistocene sediments. This is the most recent macrofossil record of a now extinct species in Tasmania. Banksia kingii is related to the extant B. saxicola. Banksia strahanensis Jordan & Hill, sp. nov. (known only from a leaf and leaf fragments and related to B. spinulosa) is described from Early to Middle Pleistocene sediments in Tasmania. This represents the third Pleistocene macrofossil record of a plant species which is now extinct in Tasmania.

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Syromyatnikova, Elena, Alexey Tesakov, Serdar Mayda, Tanju Kaya et Gerçek Saraç. « Plio-Pleistocene Amphibians and Reptiles from Central Turkey : New Faunas and Faunal Records with Comments on their Biochronological Position Based on Small Mammals ». Fossil Imprint 75, n^o 3-4 (1 décembre 2019) : 343–58. http://dx.doi.org/10.2478/if-2019-0022.

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Abstract Small fossil vertebrates from several Pliocene and Pleistocene localities in Central Anatolia (Turkey) are reviewed. Data on small mammals represent assemblages from the early Pliocene (MN 14: Nasrettinhoca 1, 2 and Hamamkarahisar A, B), and late Pliocene (MN 16: Hoyhoytepe 1, 2, 3 and Mercan 1); Early Pleistocene (MN 17: Mercan 2), and Middle Pleistocene (MQ 1/MQ 2: Yenişarbademli). The biochronology related characters of arvicolines Promimomys, Mimomys, Microtus, Lagurus and Clethrionomys are briefly discussed. Data on the systematics of fossil amphibians and reptiles is also described from these localities. The early Pliocene (MN 14) assemblages significantly add to knowledge on the herpetofaunal composition of this stratigraphic level, which until now was poorly characterized in Turkey. Remains of Pelobatidae, Bufonidae, Ranidae, Amphisbaenia and Natricinae are reported for the first time from the MN 14 biozone of Turkey. Palaeobatrachus from Mercan 1 extends the temporal range of this group in the Eastern Mediterranean into the late Pliocene. The described remains of amphibians and reptiles from Turkey span a considerable stratigraphic range from the early Pliocene to the Middle Pleistocene (time interval of about 5 Ma) and partly fill a gap in the palaeoherpetofaunal record of the Eastern Mediterranean.

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Rose, J., I. Candy, B. S. P. Moorlock, H. Wilkins, J. A. Lee, R. J. O. Hamblin, J. R. Lee, J. B. Riding et A. N. Morigi. « Early and early Middle Pleistocene river, coastal and neotectonic processes, southeast Norfolk, England ». Proceedings of the Geologists' Association 113, n^o 1 (janvier 2002) : 47–67. http://dx.doi.org/10.1016/s0016-7878(02)80006-2.

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Froese, Duane G., Derald G. Smith, John A. Westgate, Thomas A. Ager, Shari J. Preece, Amanjit Sandhu, Randolph J. Enkin et Florence Weber. « Recurring middle Pleistocene outburst floods in east-central Alaska ». Quaternary Research 60, n^o 1 (juillet 2003) : 50–62. http://dx.doi.org/10.1016/s0033-5894(03)00090-5.

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AbstractRecurring glacial outburst floods from the Yukon-Tanana Upland are inferred from sediments exposed along the Yukon River near the mouth of Charley River in east-central Alaska. Deposits range from imbricate gravel and granules indicating flow locally extending up the Yukon valley, to more distal sediments consisting of at least 10 couplets of planar sands, granules, and climbing ripples with up-valley paleocurrent indicators overlain by massive silt. An interglacial organic silt, occurring within the sequence, indicates at least two flood events are associated with an earlier glaciation, and at least three flood events are associated with a later glaciation which postdates the organic silt. A minimum age for the floods is provided by a glass fission track age of 560,000 ± 80,000 yr on the GI tephra, which occurs 8 m above the flood beds. A maximum age of 780,000 yr for the floods is based on normal magnetic polarity of the sediments. These age constraints allow us to correlate the flood events to the early-middle Pleistocene. And further, the outburst floods indicate extensive glaciation of the Yukon-Tanana Upland during the early-middle Pleistocene, likely representing the most extensive Pleistocene glaciation of the area.

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Krull, Evelyn S., Clifford H. Thompson et Jan O. Skjemstad. « Chemistry, radiocarbon ages, and development of a subtropical acid peat in Queensland, Australia ». Soil Research 42, n^o 4 (2004) : 411. http://dx.doi.org/10.1071/sr03144.

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A subtropical peat, developed on a costal plain in southern Queensland, has been studied with respect to its morphology, radiocarbon (14C) age, total organic carbon (C) content, stable C isotopic (δ13C) values, and spectroscopic characteristics (13C-NMR and FTIR). The combination of techniques allowed for an interpretation of changes in peat development over time, an assessment of paleoclimatic changes that apparently occurred during peat growth, and a comparison with perched lake sediments on Fraser Island.Geochemical data from the peat showed a relative increase in abundance of aromatic C (which may include charcoal) from the Pleistocene to the early Holocene and much decreased abundances of aromatic C thereafter. This trend may be due to changes in fire frequency from the Pleistocene–early Holocene (high fire frequency) to the early and middle Holocene (relatively low fire frequency). This interpretation is consistent with other published data from this area, showing increased aridity, increased fire frequency and dominance of sclerophyll forest during the late Pleistocene–early Holocene.Another significant geochemical change in the acid peat occurred within the middle to late Holocene. This period is characterised by highly 13C-depleted organic matter and a comparably high alkyl C (lipid) content. These data are interpreted as indicating wetter and year-round waterlogged conditions, possibly associated with poor drainage during the Holocene sea level maximum c. 5500–3000 years BP. By comparison, abundance of alkyl C decreased and δ13C values increased in the latest Holocene. The geochemical data from the acid peat point to the occurrence of a dry phase during the late Pleistocene to early Holocene and a wet phase in the middle to late Holocene, followed by another dry phase. These data correspond well with published data of 2 phases of dune formation (dry periods) in the early to middle Holocene and in the latest Holocene for North Queensland.

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Madden, Cary T. « Stegomastodon Associated With Mammuthus in Arizona During the Quaternary ». Quaternary Research 26, n^o 2 (septembre 1986) : 266–71. http://dx.doi.org/10.1016/0033-5894(86)90110-9.

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The gomphothere, Stegomastodon, is the most morphologically progressive non-elephant proboscidean in North America. Prior to the appearance of mammoths during the earliest Pleistocene, stegomastodonts held niches later occupied by those elephants. Two proboscidean specimens from near Taylor, Arizona, show that elephant-like Stegomastodon coexisted with Mammuthus in the southwestern United States during the Quaternary. Other associations of Stegomastodon and Mammuthus are known from the early and middle Pleistocene of Texas and the early Pleistocene of Nebraska. The mammoth from the Taylor locality is the oldest known from Arizona.

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Murray, Hannah, et Alastair HF Robertson. « Pliocene–Pleistocene sedimentary and geomorphologic development of the Vasilikos river catchment, S Cyprus, in relation to uplift of the Troodos ophiolite and climate-related changes ». Geological Magazine 157, n^o 4 (25 octobre 2019) : 573–602. http://dx.doi.org/10.1017/s0016756819001134.

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AbstractThe Pleistocene development of the Vasilikos River exemplifies the interaction of focused, tectonically induced surface uplift and climate-influenced changes. The resulting sediments are well exposed in Vasilikos Quarry and in the main river catchment further east. An important erosional surface incises the highest-level (oldest) fluvial conglomerates, down into Late Pliocene – Early Pleistocene open-marine mudrocks (Nicosia Formation), allowing integration with the circum-Cyprus sedimentary–geomorphic development (F1–F4 stages). To determine where the quarry deposits lie in relation to the Vasilikos river catchment, the fluvial deposits were mapped and valley profiles were constructed, revealing four main episodes, each associated with incision and distinctive fluvial deposition. Source lithology strongly influenced channel morphology, infill and adjacent slope-sediment (colluvium) composition. Palaeosols, particularly red-brown terra rossa, developed on abandoned fluvial terraces and adjacent hillslopes, especially overlying F3 surfaces. The combined evidence allows close correlation of the Vasilikos river and quarry deposits. Relatively coarse (chalky conglomerate/breccia) and fine-grained colluvium (calcareous silt – Cyprus harvara) developed especially on lower hillslopes following incision (mainly above F2 and F3 surfaces). Based on regional comparisons, overall sediment aggregation ended during the Early Pleistocene. The F1–F2 surfaces and deposits are inferred to be Middle Pleistocene, the F3 ones later Middle Pleistocene and the F4 ones near the Middle–Late Pleistocene boundary. Geomorphology and deposition were tectonically forced during strong, focused Early–Middle Pleistocene surface uplift. Coarse clastic ruff-off and palaeosol development (terra rossa) and related sediment aggradation are inferred to have increased during warm, humid periods. Late Pleistocene geomorphology and deposition were more influenced by climatic change, with semi-perennial streamflow, rapid sediment aggradation and palaeosol (terra rossa) development during warm, humid periods (interglacials). Cooler (glacial) periods enhanced fluvial-incision, sediment-bypassing and hillslope colluvial processes (e.g. frost shattering, downslope creep and mass flow) when sediment transport (bypassing) exceeded sediment supply. Neotectonic faulting affected the catchment but did not greatly affect geomorphology or sediment supply. Although climate / climate change (and eustatic sea-level change) had an important influence, tectonics is interpreted as the fundamental driver of geomorphological development and fluvial sedimentation, with implications for other areas, regionally to globally.

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Miño-Boilini, Ángel R., et Alfredo A. Carlini. « The Scelidotheriinae Ameghino, 1904 (Phyllophaga, Xenarthra) from the Ensenadan–Lujanian Stage/Ages (Early Pleistocene to Early-Middle Pleistocene–Early Holocene) of Argentina ». Quaternary International 210, n^o 1-2 (décembre 2009) : 93–101. http://dx.doi.org/10.1016/j.quaint.2009.06.016.

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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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Mayhew, D. F., F. E. Dieleman, A. A. Slupik, L. W. van den Hoek Ostende et J. W. F. Reumer. « Small mammal assemblages from the Quaternary succession at Moriaanshoofd (Zeeland, the Netherlands) and their significance for correlating the Oosterschelde fauna ». Netherlands Journal of Geosciences - Geologie en Mijnbouw 93, n^o 3 (24 avril 2014) : 119–34. http://dx.doi.org/10.1017/njg.2014.6.

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AbstractWe investigated fossil small mammals from a borehole near Moriaanshoofd (Zeeland, southwest Netherlands) in order to get better insights in the fossil mammal faunas that are found in the subsurface in the southwestern Netherlands, and to investigate the age and provenance of the mammal fauna that is being dredged from the deep tidal gullies in the nearby Oosterschelde estuary. The record in the borehole covers Gelasian (Early Pleistocene) to Holocene deposits, represented by six formations. Thirty-nine specimens of small mammals were obtained from the borehole. These fossils derived from the Early Pleistocene marine Maassluis Formation and from directly overlying deposits of a Late Pleistocene age. During Weichselian times (33–24 ka), a proto-Schelde River shaped the northern Oosterschelde area. The river reworked substantial amounts of Early and Middle Pleistocene deposits. At the base of the Schelde-derived fluvial sequence (regionally described as the Koewacht Formation), Gelasian vertebrate faunas were concentrated in the channel lag. The Late Pleistocene channel lag is almost certainly the main source for the rich Early Pleistocene vertebrate faunas with larger mammals dredged from the Oosterschelde.

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Manzi, Giorgio. « Before the Emergence of Homo sapiens : Overview on the Early-to-Middle Pleistocene Fossil Record (with a Proposal about Homo heidelbergensis at the subspecific level) ». International Journal of Evolutionary Biology 2011 (4 mai 2011) : 1–11. http://dx.doi.org/10.4061/2011/582678.

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The origin of H. sapiens has deep roots, which include two crucial nodes: (1) the emergence and diffusion of the last common ancestor of later Homo (in the Early Pleistocene) and (2) the tempo and mode of the appearance of distinct evolutionary lineages (in the Middle Pleistocene). The window between 1,000 and 500 thousand years before present appears of crucial importance, including the generation of a new and more encephalised kind of humanity, referred to by many authors as H. heidelbergensis. This species greatly diversified during the Middle Pleistocene up to the formation of new variants (i.e., incipient species) that, eventually, led to the allopatric speciation of H. neanderthalensis and H. sapiens. The special case furnished by the calvarium found near Ceprano (Italy), dated to 430–385 ka, offers the opportunity to investigate this matter from an original perspective. It is proposed to separate the hypodigm of a single, widespread, and polymorphic human taxon of the Middle Pleistocene into distinct subspecies (i.e., incipient species). The ancestral one should be H. heidelbergensis, including specimens such as Ceprano and the mandible from Mauer.

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Articles de revues sur le sujet « Early Middle Pleistocene »

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