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Vermeersch P.M.,Catholic University of Leuven | Van Neer W.,Royal Belgian Institute Of Natural Sciences | Van Neer W.,Catholic University of Leuven
Quaternary Science Reviews | Year: 2015

The reconstruction of the environment and the human population history of the Nile Valley during the Late Pleistocene have received a lot of attention in the literature thus far. There seems to be a consensus that during MIS2 extreme dry conditions prevailed over north-eastern Africa, which was apparently not occupied by humans. The Nile Valley seems to be an exception; numerous field data have been collected suggesting an important population density in Upper Egypt during MIS2. The occupation remains are often stratified in, or at least related to, aeolian and Nile deposits at some elevation above the present-day floodplain. They are rich in lithics and animal bones, mainly fish, illustrating the exploitation of the Nile Valley by the Late Palaeolithic inhabitants. The fluvial processes active during that period have traditionally been interpreted as a continuously rising highly braided river.In this paper we summarize the evidence thus far available for the Late Pleistocene on the population densities in the Nile Valley, and on the models of Nilotic behaviour. In the discussion we include data on the environmental conditions in Eastern Africa, on the aeolian processes in the Western Desert of Egypt derived from satellite images, 14C and OSL dates, in order to formulate a new model that explains the observed high remnants of aeolian and Nilotic deposits and the related Late Palaeolithic sites. This model hypothesizes that, during the Late Pleistocene, and especially the LGM, dunes from the Western Desert invaded the Nile Valley at several places in Upper Egypt. The much reduced activity of the White Nile and the Blue Nile was unable to evacuate incoming aeolian sand and, as a consequence, several dams were created in the Upper Egyptian Nile Valley. Behind such dams the created lakes offered ideal conditions for human subsistence. This model explains the occurrence of Late Palaeolithic hunter-fisher-gatherers in a very arid environment with very low Nile flows, even in late summer. © 2015 The Authors.

Lee Y.-N.,Korea Institute of Geoscience and Mineral Resources | Barsbold R.,Mongolian Academy of science | Currie P.J.,University of Alberta | Kobayashi Y.,Hokkaido University | And 4 more authors.
Nature | Year: 2014

The holotype of Deinocheirus mirificus was collected by the 1965 Polish-Mongolian Palaeontological Expedition at Altan Uul III in the southern Gobi of Mongolia. Because the holotype consists mostly of giant forelimbs (2.4 m in length) with scapulocoracoids, for almost 50 years Deinocheirus has remained one of the most mysterious dinosaurs. The mosaic of ornithomimosaur and non-ornithomimosaur characters in the holotype has made it difficult to resolve the phylogenetic status of Deinocheirus. Here we describe two new specimens of Deinocheirus that were discovered in the Nemegt Formation of Altan Uul IV in 2006 and Bugiin Tsav in 2009. The Bugiin Tsav specimen (MPC-D 100/127) includes a left forelimb clearly identifiable as Deinocheirus and is 6% longer than the holotype. The Altan Uul IV specimen (MPC-D 100/128) is approximately 74% the size of MPC-D 100/127. Cladistic analysis indicates that Deinocheirus is the largest member of the Ornithomimosauria; however, it has many unique skeletal features unknown in other ornithomimosaurs, indicating that Deinocheirus was a heavily built, non-cursorial animal with an elongate snout, a deep jaw, tall neural spines, a pygostyle, a U-shaped furcula, an expanded pelvis for strong muscle attachments, a relatively short hind limb and broad-tipped pedal unguals. Ecomorphological features in the skull, more than a thousand gastroliths, and stomach contents (fish remains) suggest that Deinocheirus was a megaomnivore that lived in mesic environments. © 2014 Macmillan Publishers Limited. All rights reserved.

Dulie V.,Royal Belgian Institute Of Natural Sciences | Zhang Y.,U.S. National Center for Atmospheric Research | Salathe E.P.,University of Washington
Journal of Climate | Year: 2013

Trends in extreme temperature and precipitation in two regional climate model simulations forced by two global climate models are compared with observed trends over the western United States. The observed temperature extremes show substantial and statistically significant trends across the western United States during the late twentieth century, with consistent results among individual stations. The two regional climate models simulate temporal trends that are consistent with the observed trends and reflect the anthropogenic warming signal. In contrast, no such clear trends or correspondence between the observations and simulations is found for extreme precipitation, likely resulting from the dominance of the natural variability over systematic climate change during the period. However, further analysis of the variability of precipitation extremes shows strong correspondence between the observed precipitation indices and increasing oceanic Ni~no index (ONI), with regionally coherent patterns found for the U.S. Northwest and Southwest. Both regional climate simulations reproduce the observed relationship with ONI, indicating that the models can represent the large-scale climatic linkswith extreme precipitation. The regional climatemodel simulations use theWeatherResearch and Forecasting (WRF) Model and Hadley Centre Regional Model (HadRM) forced by the ECHAM5 and the Hadley Centre ClimateModel (HadCM) global models for the 1970-2007 time period. Comparisons are made to station observations from the Historical Climatology Network (HCN) locations over the western United States. This study focused on temperature and precipitation extreme indices recommended by the Expert Team on Climate Change Detection Monitoring and Indices (ETCCDMI). © 2013 American Meteorological Society.

Nagy Z.T.,Royal Belgian Institute Of Natural Sciences
Organisms Diversity and Evolution | Year: 2010

DNA studies have overwhelming importance in biological science. The aim of this paper is to present a compact and hands-on summary of widely available tissue preservation methods by listing dry, fluid/buffered and freezing techniques. Thereby, practical aspects, advantages and disadvantages, safety and feasibility issues of each method are discussed and compared.

Bultynck P.,Royal Belgian Institute Of Natural Sciences
Bulletin de l'Institut Royal des Sciences Naturelles de Belqique, Sciences de la Terre | Year: 2011

For the first time the complete conodont fauna from the GSSP for the base of the Givetian at Jebel Mech Irdane in the Tafilalt (SE Morocco) is described. The conodont faunas described by BULTYNCK in 1987 from the Bou Tchrafine ridge in the same area and from the Jebel Ou Driss (Mader, SE Morocco) in 1989 are updated. Many new morphotypes of Polygnathus linguiformis and other conodont species are described. Polygnathus amphora, P. pseudoeiflius and ¡hollardi are established as new species.

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