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131.
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
132.
描述了一件象属( Elephas) 的右上臼齿化石。标本产自查谟紧靠上西瓦立克亚群巨砾岩组( Boulder Conglomerate Formation) 之上的砂质、粉砂质泥岩夹砾石层中,化石地点位于查谟市南10 km,Kharian 村北约500 m 处。根据齿板数、齿脊频率、釉质层厚度、冠高指数、绝对大小和齿长/齿高指数等牙齿形态参数,暂时将之归为 Elephas cf. E. maximus indicus。还简短讨论了象属的地理分布和地质时代。 相似文献
133.
根据牙形类Baltoniodus? triangularis的首现,中奥陶统和大坪阶底界已界定于湖北宜昌黄花场剖面大湾组底界之上10.57m.对黄花场剖面以及邻近的大坪剖面大湾组疑源类研究表明,某些疑源类属种具有生物地层学意义,其首现可用于识别奥陶系下/中统界线. 相似文献
134.
TONI BÜRGIN 《Zoological Journal of the Linnean Society》1990,100(4):379-391
New well-preserved specimens of Peltopleurus lissocephalus Brough, 1939, a small actinopterygian fish of the Alpine Middle Triassic, are described. Some of them show a highly modified anal fin, with a brush-shaped holdfast device and a gonopodium-like structure, possibly used during mating behaviour. Additional examples of modified anal fins are reported for the genera Cephaloxenus and Habroichthys. Evidence for viviparity within the genus Saurichthys , found at the same localities, is discussed and compared with earlier reports of the phenomenon. A comparison is made of the different reproductive strategies used in some Middle Triassic actinopterygian fishes. 相似文献
135.
The Latemar is a mainly aggrading platform, but shows repeated backstepping during its entire development. The behaviour of the slope does not reflect accommodation changes and lateral consistencies of the lagoonal interior; the Latemar contemporaneously reveals different, even contrasting depositional characteristics. The slope of the late stage platform evolution corresponds at least partially to the base-of-slope apron model. Controlling factors on slope evolution are of tectonic (proximity of the Stava Line) and autocyclic (repeated oversteepening) nature. Other factors are insignificant and/or overprinted. The reef-facies at Latemar reveals a complex facies pattern; it varies along and across the margin and is rich in encrusting sponges, corals, biogenic crusts and Microproblematica. Some biota or fossil assemblages—e.g. foraminifers (Abriolina mediterranea, Turriglomina scandonei) or Tubiphytes multisiphonatus thrombolites—have not been described in the Dolomites before. Biostratigraphic evidence from the uppermost reef-facies confirms a mainly Anisian age of the outcropping platform interior. 相似文献
136.
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138.
桂西和黔南中三叠世珊瑚 总被引:1,自引:0,他引:1
文内描述中三叠世安尼阶(Anisian)珊瑚化石分别采自桂西田阳板纳组和黔南贵阳青岩青岩组。板纳组珊瑚群中建立Pentasmilia guangxiensisgen.etsp.nov.,该新属种有5条第一周期原生隔片甚至有5条第二周期后生隔片,以此不同于有6条第一周期原生隔片和有6条第二周期后生隔片的石珊瑚类(scleractinians)的珊瑚。产于板纳组的另一新属种Radiophyllia astylatusgen.etsp.nov.,其隔片的排列格式与前人归纳的隔片周期插入示意图甚似,但它却发生在中生代最早期(Anisian)珊瑚的骸体内。文中还对青岩组的Pamiroseris silesiaca作了重新描述。 相似文献
139.
Oryctocephalid trilobites from Lower Middle Cambrian strata of the eastern Anti-Atlas, Morocco, are the first described Oryctocephalidae known from Africa. They represent the new genus and species Shergoldiella vincenti. However, a similar species was earlier described as Tonkinella sequei Liñán et Gozalo, 1999, from coeval lower Middle Cambrian strata of the Iberian Chains, northern Spain. This Iberian species is imperfectly preserved and assigned herein to Shergoldiella with reservations. If this assignment is correct, it would reinforce earlier suggested correlations between Morocco and Spain. Nevertheless, Shergoldiella suggests a morphocline from a typical oryctocephalid-type morphology towards the Tonkinella-type morphology. Close similarity with Ovatoryctocara ovata suggests a similar stratigraphic position in accordance with earlier suggested intercontinental correlations. 相似文献
140.
JAIME LIRA† ANNA LINDERHOLM‡ CARMEN OLARIA§ MIKAEL BRANDSTRÖM DURLING¶ M. THOMAS P. GILBERT HANS ELLEGREN†† ESKE WILLERSLEV KERSTIN LIDÉN‡ JUAN LUIS ARSUAGA† ANDERS GÖTHERSTRÖM†† 《Molecular ecology》2010,19(1):64-78
Multiple geographical regions have been proposed for the domestication of Equus caballus . It has been suggested, based on zooarchaeological and genetic analyses that wild horses from the Iberian Peninsula were involved in the process, and the overrepresentation of mitochondrial D1 cluster in modern Iberian horses supports this suggestion. To test this hypothesis, we analysed mitochondrial DNA from 22 ancient Iberian horse remains belonging to the Neolithic, the Bronze Age and the Middle Ages, against previously published sequences. Only the medieval Iberian sequence appeared in the D1 group. Neolithic and Bronze Age sequences grouped in other clusters, one of which (Lusitano group C) is exclusively represented by modern horses of Iberian origin. Moreover, Bronze Age Iberian sequences displayed the lowest nucleotide diversity values when compared with modern horses, ancient wild horses and other ancient domesticates using nonparametric bootstrapping analyses. We conclude that the excessive clustering of Bronze Age horses in the Lusitano group C, the observed nucleotide diversity and the local continuity from wild Neolithic Iberian to modern Iberian horses, could be explained by the use of local wild mares during an early Iberian domestication or restocking event, whereas the D1 group probably was introduced into Iberia in later historical times. 相似文献