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1.
Thomas C. Hauck 《L'Anthropologie》2015,119(5):659-675
Our view of MP cultural variability is blurred by site-specific problems as well as inadequate research concepts. The former are inherent in current fieldwork methodology and in the archaeological record itself. Excavation of Palaeolithic sites generally catches only parts of the entire archaeological record and thus leaves us with the sample size problem. Moreover, resolution of the archaeological record is often limited by the palimpsest problem which is especially given in spatially restricted sites (e.g. caves) coupled with a low sedimentation rate. Many research concepts not only neglect the resolution problem but also lack the consideration of scale when it comes to archaeological interpretation. Our aim is not to reinterpret the Levantine Middle Palaeolithic in the light of these challenges as this is outside the scope of this paper. Archaeological resolution and scale are nevertheless taken as guidelines for the integration of the Hummal Mousterian in a broader context. In doing so, we give a short review of current knowledge and show how a scale-sensitive approach can inform us about various aspects of the Levantine Middle Palaeolithic. 相似文献
2.
Lutz Christian Maul Krister T. Smith Georgy Shenbrot Angela A. Bruch Fabio Wegmüller Jean-Marie Le Tensorer 《L'Anthropologie》2015,119(5):676-686
We present a first look at the microvertebrate fauna of the Middle Pleistocene site of Hummal in Central Syria. Some 2000 microvertebrate remains (1200 mammalian; 230 reptilian; 600 unidentified) were found in unit G/layer 17 by screen-washing sediments in an area of 4 m2. The following taxa have been identified: Reptilia: Agaminae indet., Gekkota indet., Lacertidae indet. (2–3 taxa), Eryx sp., Natricinae indet.; and Mammalia: Crocidurinae indet., Chiroptera indet., Lepus sp., Arvicolinae indet., Ellobius sp., Microtus sp., Murinae indet. (large form), Mus sp., Meriones sp., Gerbillus sp. The presence of Ellobius indicates a Middle Pleistocene age of the fauna. This genus does not occur in Syria today, but is recorded in Israel in Late Acheulean to Early Mousterian sites. In North Africa, the occurrence of this genus is restricted to the early part of the Middle Pleistocene. The ecological requirements of the nearest living relatives of the recorded taxa indicate mainly open habitats, but also the presence of vegetation and wet conditions, at least close to the site. Lepus, Ellobius, Meriones, Gerbillus, and Eryx live to various extents in steppes, semi-deserts, and deserts. Various extant species of large murids that come into consideration occupy a variety of wooded habitats, grassland and savannah and require the presence of water. Hummal offers the most detailed Pleistocene portrait yet of hominin palaeoenvironment in an area that, at the end of the Pleistocene, became known as part of the Fertile Crescent. 相似文献
3.
This paper examines spatial patterning and settlement dynamics of early Middle Paleolithic hominins at Douara Cave, located on the northern edge of the Syrian Desert. The analyzed material came from our 1984 excavations of Horizons IVB–IVD, techno-typologically assigned to the Tabun D-type Levantine Mousterian (ca. 250 to 130 ka). Two findings are reported. One is the existence of spatial organization in the cave interior. Analysis of the field records shows that the occupation floor of the early Middle Paleolithic at Douara was well-organized into specific activity areas with a focal area of intensive activities close to the back wall. This suggests that the organized use of space known at late Middle Paleolithic sites like Tor Faraj, Jordan, is also applicable to the early Middle Paleolithic. Second, this paper discusses the functional role of this cave within the regional settlement system. A range of features characterizing its living floor(s) point to a very low occupational intensity, undoubtedly reflecting adaptation and particular land use patterns in the arid environments of this region. Moreover, this pattern, along with the division of interior space, seems to have remained consistent through multiple early Middle Paleolithic levels (IVB–IVD). These observations suggest that Douara Cave was a short-term camp embedded in a regional settlement system in the arid environments of this period. 相似文献
4.
Alan Mann Bernard Vandermeersch Anne Delagnes Jean-Franois Tournepiche 《Comptes Rendus Palevol》2007,6(8):581-589
The cave of Artenac is located about 20 km northeast of Angouleme, in the commune of Saint-Mary (Charente). In 1995 and 1996, two fragmentary hominine skull bones, a maxilla and a frontal, were uncovered during excavations in Mousterian levels of the cave. Biostratigraphic analyses of the abundant mammalian fauna place the Mousterian occupation of the cave at the beginning of Oxygen Isotope Stage 5. Although both bones come from adults, aspects of their morphology indicate they could derive from two individuals of different ages at death. The two bones are relatively fragmentary, but sufficient detail has been preserved, including an inflated maxillary region lacking an infra-orbital depression (or fossa canina) and the shape of the forehead, to establish their identity as Neandertals. 相似文献
5.
Cyril Montoya Adrian Balasescu Sébastien Joannin Vincent Ollivier Jérémie Liagre Samvel Nahapetyan Ruben Ghukasyan David Colonge Boris Gasparyan Christine Chataigner 《Journal of human evolution》2013
The open-air site of Kalavan 1 is located in the Aregunyats mountain chain (at 1640 m above sea level) on the northern bank of Lake Sevan. It is the first Upper Palaeolithic site excavated in Armenia. Led by an Armenian-French team, several excavations (2005–2009) have revealed a well preserved palaeosoil, dated to around 14,000 BP (years before present), containing fauna, lithic artefacts, as well as several hearths and activity areas that structure the settlement. The initial studies enable placement of the site in its environment and justify palaeoethnological analysis of the Epigravettian human groups of the Lesser Caucasus. 相似文献
6.
Jean-Marie Le Tensorer Hélène Le Tensorer Pietro Martini Vera von Falkenstein Peter Schmid Juan José Villalain 《L'Anthropologie》2015,119(5):581-594
At present, the oldest traces of human cultures are found in Eastern Africa. New discoveries set anew the questions about human and animal dispersal into Eurasia. For over 1.8 million years, humans have been present in the Levant. An extensive program of surveys and excavations in the Syrian Desert showed that this part of the world was a very ancient land of settlement. In Central Syria, the oldest site, Aïn al Fil in the region of El Kowm, was excavated in 2008 and 2010. The lithic industry in the lowest layer can be characterized by numerous unretouched flakes, pebble-tools and core-like artefacts. This assemblage is typical in a broad sense of archaic Palaeolithic the debitage of which corresponds to mode 1. From a techno-typological point of view, this industry tallies quite well with the so-called Oldowan stage. It shows remarkable similarities with the oldest African assemblages. From a chronologic point of view, these levels occur before three positive events in the Matuyama paleomagnetic sequence. It seems consistent to place the Oldowan sequence around 1.8 Ma BP within the Olduvai subchron or just before Olduvai/Matuyama reversal limit. Together with those of the neighbouring site Hummal, these levels would be the oldest traces of human presence ever found in Syria. In the Levant, the first humans not only occupied favourable zones but regularly ventured deep into less welcoming environments suggesting an astonishing flexibility in their behavioural and survival skills. 相似文献
7.
Sequential settlement and site dependence in a migratory raptor 总被引:3,自引:0,他引:3
Sergio Fabrizio; Blas Julio; Forero Manuela G.; Donazar Jose Antonio; Hiraldo Fernando 《Behavioral ecology》2007,18(5):811-821
Habitat selection models, such as the ideal free, ideal despotic,site-dependent, and conspecific cuing models, are of great importanceto behavioral ecologists given their capability to predict habitatdistributions and to link individual behavior to populationprocesses. However, there have been relatively few field testsof their predictions. We tested the 4 models by studying theprocess of sequential settlement on territory in 2 distant populationsof a migratory raptor, the black kite Milvus migrans. Resultswere mainly consistent with the site-dependent model: on arrival,kites settled on progressively lower quality territories, andearlier arriving individuals were older, larger, and in betterbody condition than later arriving ones, leading to a state-dependentarrival sequence also predicted by a previous theoretical modelof settlement pattern. Occupation of superior territories bysuperior phenotypes resulted in cascading advantages for earlierarriving individuals in terms of subsequent reproductive performance.At the population level, the populations expanded/retractedfrom lower quality sites during population increases/declines.The above scenario was consistent across the 2 populations,and a review of the literature uncovered a remarkably consistentpicture of state-dependent arrival, progressive monopolizationof best quality sites, and cascading effects on subsequent breedingperformance. We propose as a general paradigm of sequentialsettlement the following process: 1) arrival date is a reliablesurrogate of phenotype quality, 2) early-arriving individualshave preferential access to the best quality sites and partners,3) the above conditions cascade into a number of benefits ultimatelyrelated to higher fitness for earlier arriving individuals. 相似文献
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The nano-pico second backbone dynamics of the ribonuclease binase, homologous to barnase, is investigated with (15)N, (13)C NMR relaxation at 11.74 and 18.78 T and with a 1.1 ns molecular dynamics simulation. The data are compared with the temperature factors reported for the X-ray structure of this enzyme. The molecular dynamics and X-ray data correspond well and predict motions in the loops 56-61 and 99-104 that contain residues that specifically recognize substrate and are catalytic (His101), respectively. In contrast, the (15)N relaxation data indicate that these loops are mostly ordered at the nano-pico second time scale. Nano-pico second motions in the recognition loop 56-61 are evident from (13)CO-(13)C cross relaxation data, but the mobility of the catalytic loop 99-104 is not detected by (13)CO cross relaxation either. From the results of this and previous work [Wang, L., Pang, Y., Holder, T., Brender, J. R., Kurochkin, A., and Zuiderweg, E. R. P. (2001) Proc. Natl. Acad. Sci. U.S.A., 98, 7684-7689], the following dynamical characterization of the active site area of binase emerges: a beta sheet, rigid at all probed time scales, supports the catalytic residue Glu 72. Both substrate-encapsulating loops are mobile on both fast and slow time scales, but the fast motions of the loop which contains the other catalytic residue, His 101, as predicted by B-factors and computational molecular dynamics is not detected by NMR relaxation. This work strongly argues for the use of several measures in the study of protein dynamics. 相似文献
10.
Multiple instances of low-potential electron-transport pathway inhibitors that affect the structure of the cytochrome (cyt) bc(1) complex to varying degrees, ranging from changes in hydroquinone (QH(2)) oxidation and cyt c(1) reduction kinetics to proteolytic accessibility of the hinge region of the iron-sulfur-containing subunit (Fe/S protein), have been reported. However, no instance has been documented of any ensuing change on the environment(s) of the [2Fe-2S] cluster. In this work, this issue was addressed in detail by taking advantage of the increased spectral and spatial resolution obtainable with orientation-dependent electron paramagnetic resonance (EPR) spectroscopic analysis of ordered membrane preparations. For the first time, perturbation of the low-potential electron-transport pathway by Q(i)-site inhibitors or various mutations was shown to change the EPR spectra of both the cyt b hemes and the [2Fe-2S] cluster of the Fe/S protein. In particular, two interlinked effects of Q(i)-site modifications on the Fe/S subunit, one changing the local environment of its [2Fe-2S] cluster and a second affecting the mobility of this subunit, are revealed. Remarkably, different inhibitors and mutations at or near the Q(i) site induce these two effects differently, indicating that the events occurring at the Q(i) site affect the global structure of the cyt bc(1). Furthermore, occupancy of discrete Q(i)-site subdomains differently impede the location of the Fe/S protein at the Q(o) site. These findings led us to propose that antimycin A and HQNO mimic the presence of QH(2) and Q at the Q(i) site, respectively. Implications of these findings in respect to the Q(o)-Q(i) sites communications and to multiple turnovers of the cyt bc(1) are discussed. 相似文献
11.
Jean-Marie Le Tensorer Vera von Falkenstein Hélène Le Tensorer Peter Schmid Sultan Muhesen 《L'Anthropologie》2011,(2):247
The spring site of Hummal is located in Central Syria, near the village of El Kowm between the Euphrates basin and the desert steppe stretching from Palmyra to Deir-ez-Zor. In 1966 the well was noted in a survey as Bir Onusi and a short preliminary study was carried out at the beginning of the 1980s. Since 1997, the Institute for Prehistory and Archaeological Science of the University of Basel has undertaken a complete interdisciplinary research program of this major site under the direction of J.M Le Tensorer, supported by the Swiss National Science Foundation and associated with the Directorate General of Antiquities and Museums of Syria under the direction of S. Muhesen. The site of Hummal is a prominent mound at an artesian spring built out of the sediments, which piled up during the whole Quaternary. Tectonic faults in the bed rock enabled the underlying water in a karstic system to flow out into a dolina, which trapped lacustrine, limnic and aeolian sediments since the Oldest Pleistocene. The impressive stratigraphy – 20 m high – comprises 23 geological units preserving a great number of archaeological levels. It covers an extremely long period of time ranging from the Oldest Palaeolithic (Oldowan) to Upper Palaeolithic (Aurignacian) over more than a million years. This impressive Old and Middle Palaeolithic sequence comprises several layers of Oldowan-like assemblage (23-16), an Acheuleo-Tayacian complex (14-13), five layers of Yabrudian (12-8) at least four levels of Hummalian (7, 6c, 6b, 6a) and a thick sediment complex with 8 Mousterian layers, each of them liable to be subdivided into several sublayers. The lithic industry in the lowest levels of the Hummal sequence, associated with abundant remains of large mammals, can be characterized by non-modified, quite fresh flakes, with, once in a while, traces of use but never bearing intentional retouches. Theses flakes are found with pebble-tools: choppers, chopping-tools, polyhedrons, bolas and core-like artifacts. This assemblage is typical in a broad sense of archaic Palaeolithic whose debitage corresponds to mode 1. From a techno-typological point of view, this industry tallies quite well with the so-called Oldowan stage. It shows remarkable similarities with the oldest assemblages at Ubeidiya but, so far, with no occurrence of bifacial knapping. If the layers 17 and 18 of Hummal relate to this period dating back to 1.6 to 1.2 million years, these levels would be the oldest ones ever found in central Syria. However, as we have no absolute dating at our disposal so far, we will remain careful in assigning a chronological time span for these layers. For this area, from a stratigraphic point of view, the Oldowan levels of Hummal occur before the Acheulean and certainly before the Acheulean sequence of El Meirah (region of El Kowm) which is itself related to the period before Matuyama-Brunhes paleomagnetic reverse. Dating of the lowest sequence of Hummal is underway. If we take into account stratigraphic and techno-typological observations, we assume that the Oldowan-like levels of the site should be older than one million years at least. The sequence of Hummal is one of the largest in the Near-East. Therefore, it can be regarded as a key-site for world prehistory. 相似文献
12.
Conformational dynamics are an important property of ribozymes and other RNA molecules but there is currently only limited information on the relationship between dynamics and RNA function. A recent structural study of the lead-dependent ribozyme, known as the leadzyme, showed significant dynamics at the active site and indicated that a structural rearrangement is required for the reaction to proceed from the ground to the transition state. In this work, microsecond-to-millisecond dynamics of the leadzyme are probed by analysis of the power dependence of (13)C NMR relaxation times in the rotating frame (T(1)(rho)). These results revealed a wide range of conformational dynamics for various residues in the leadzyme. For residue A25 in the active site, the power dependence of T(1)(rho) yielded an exchange lifetime similar to that previously measured by line-shape analysis, and provides an important calibration of this T(1)(rho) methodology for probing the dynamics of macromolecules. Strong evidence was also found for a previously suggested dynamic network of hydrogen bonds stabilizing the GAAA tetraloop motif. Within the active site of the leadzyme, internal motions are observed on a wide variety of time scales, suggesting a complex landscape of accessible states, and potential correlations between observed motions and catalytic function are discussed. These results demonstrate that the power dependence of (13)C T(1)(rho) relaxation times provides a valuable method for probing dynamics in nucleic acids. 相似文献
13.
M. GOREN 《Zoological Journal of the Linnean Society》1972,51(2):141-145
Pseudophoxinus zeregi (Heckel) and P. (Pararhodeus) drusensis (Pellegrin) have been examined from populations near their respective type localities. It was found that there is no basis for the subgenus Pararhodeus and that the two forms are best regarded as subspecies of Pseudophoxinus zeregi. 相似文献
14.
Maasai settlements in Amboseli are distributed in a pattern which reflects various physical and biological characteristics of the landscape. The settlements avoid hillslope gradients exceeding 0.08, and the lower sections of long hillsides, which receive large amounts of runoff. Long, relatively high hillslopes are difficult for exhausted cattle to climb at the end of the dry season, and even the welldrained sites at the upper ends of these slopes are not commonly used. Deep, poorly drained, and light-colored soils are avoided because they affect the comfort of humans, and especially the milk production of cattle. The settlements are located away from dense tree and bush vegetation because of the danger of predators, but during occupation of the site important changes in the vegetation are wrought by the use of trees for settlement construction and firewood. The reasons for the pattern were elucidated by making a set of systematic measurements of settlement distributions and various environmental factors. The conclusions of this analysis were then checked and extended through conversations with Maasai elders. These latter exhibited a sophisticated knowledge of environmental characteristics and processes which is reflected in their choice of settlement sites. Such knowledge has commonly been overlooked by other writers on the subject of pastoralism. 相似文献
15.
M. Mansour 《Journal of Applied Entomology》2010,134(3):234-242
The possibility of controlling the codling moth Cydia pomonella (Linnaeus) using an attract and kill approach as an alternative to chemical sprays with contact insecticides was investigated in widely separated orchards. The results of a 4‐year study have shown that, using an attract and kill approach, three applications/season kept infestation rates in treated orchards below the economic injury level except in one with a too high codling moth population density. The mean number of male codling moths/trap/week in attract and kill‐treated orchards was much lower in comparison with control orchards which were treated with the usual cover sprays of insecticides. The results also showed that the efficacy of attract and kill under orchard conditions decreased with time and the relationship between time effect and codling moth death rate was very strong. These data indicate that the attract and kill technique applied at a rate of three application per season resulted in good control of codling moth in well managed orchards in Syria. 相似文献
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Summary The site of settlement of barnacles (Balanus improvisus) attached on shells of bluemussels (Mytilus edulis) was mapped from a sample of mussels collected in the Baltic Sea. Most barnacles had settled near the siphonal apertures of the mussel. An experiment was made to measure the disadvantages and advantages that living in close association brings to barnacles and mussels. The barnacles on shells of living mussels were shown to grow significantly faster than those on empty mussel shells. Presence of barnacles had no effects on growth of mussels. The two-species association under study was demonstrated to be a case of commensalism. 相似文献
18.
The motions of water molecules, the acyl moiety, the catalytic triad, and the oxyanion binding site of acyl-chymotrypsin were studied by means of a stochastic boundary molecular dynamics simulation. A water molecule that could provide the nucleophilic OH? for the deacylation stage of the catalysis was found to be trapped between the imidazole ring of His-57 and the carbonyl carbon of the acyl group. It makes a hydrogen bond with the Nε2 of His-57 and is heldin place through a network of hydrogen-bonded water molecules in theactive site. The water molecule was found as close as 2.8 Å to the carbonyl carbon. This appears to be due to the constraints imposed by nonbonded interaction in the active site. Configurations were found in which one hydrogen of the trapped water shared a bifurcated hydrogen bond with His-57-Nε2 and Ser-195-0γ with the water oxygen very close to the carbonyl carbon. The existence of such a water molecule suggests that large movement of the His-57 imidazole ring between positions suitable for providing general-base catalyzed assistance and for providing general-acid catalyzed assistance may notbe required during the reaction. The simulation indicates that the side chains of residues involved in catalysis (i.e., His-57, Ser-195, and Asp-102) are significantly less flexible than other side chains in the protein. The 40% reduction in rms fluctuations is consistent with a comparable reduction calculated from the temperature factors obtained in the X-ray crystal-lographic data of γ-chymotrypsin. The greater rigidity of active site residues seems to result from interconnected hydrogen bonding networks among the residues and between the residues and the solvent water in the active site. © Wiley-Liss, Inc. 相似文献
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The recombinant antibody fragment scFv(F8), which recognizes the coat protein of the plant virus AMCV, is characterized by peculiar high in vitro stability and functional folding even in reducing environments, making it fit for designing stable antibodies with desired properties. Mutagenesis and functional analysis evidenced two residues, at positions 47 and 58 of the V(H) chain, playing a crucial role in the antigen binding recognition. Here, we used a computational procedure to assess the effects of these mutations on the stability, structure and dynamics of the antigen-binding site. Structural models of the wild type scFv(F8) and of its H47 and H58 mutants were built by homology modelling and assessed by multiple 15.5ns of molecular dynamics simulations. Computational results indicate that the 47H substitution strongly affects the CDR-H(2) conformation, destabilizes the V(H)/V(L) interface and confers high conformational flexibility to the antigen-binding site, leading the mutant to functional loss. The mutation at position H58 strenghtens the binding site, bestowing a high antigen specificity on the mutant. The essential dynamics and the analysis of the protein-solvent interface further corroborate the correspondence between the extent of the structurally-determined flexibility of the binding site with the different functional behaviours proved by the wild-type and its mutants. These results may have useful implications for structure-based design of antibody combining site. 相似文献