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Yang, T.L., He, W.H., Zhang, K.X., Wu, S.B., Zhang, Y., Yue, M.L., Wu, H.T. & Xiao, Y.F., November 2015. Palaeoecological insights into the Changhsingian–Induan (latest Permian–earliest Triassic) bivalve fauna at Dongpan, southern Guangxi, South China. Alcheringa 40, xxx–xxx. ISSN 0311-5518.

The Talung Formation (latest Permian) and basal part of Luolou Formation (earliest Triassic) of the Dongpan section have yielded 30 bivalve species in 17 genera. Eight genera incorporating 11 species are systematically described herein, including three new species: Nuculopsis guangxiensis, Parallelodon changhsingensis and Palaeolima fangi. Two assemblages are recognized, i.e., the Hunanopecten exilisEuchondria fusuiensis assemblage from the Talung Formation and the Claraia dieneri–Claraia griesbachi assemblage from the Luolou Formation. The former is characterized by abundant Euchondria fusuiensis, an endemic species, associated with other common genera, such as Hunanopecten, which make it unique from coeval assemblages of South China. A palaeoecological analysis indicates that the Changhsingian bivalve assemblage at Dongpan is diverse and represented by various life habits characteristic of a complex ecosystem. This also suggests that redox conditions were oxic to suboxic in deep marine environments of the southernmost Yangtze Basin during the late Changhsingian, although several episodes of anoxic perturbations and declines in palaeoproductivity saw deterioratation of local habitats and altered the taxonomic composition or population size of the bivalve fauna.

Tinglu Yang [], School of Earth Sciences, China University of Geosciences, 388 Lumo Road, Hongshan, Wuhan 430074, PR China; Weihong He* [] and Kexin Zhang [], State Key Laboratory of Biogeology and Environmental Geology, School of Earth Sciences, China University of Geosciences, 388 Lumo Road, Hongshan, Wuhan 430074, PR China; Shunbao Wu [], Yang Zhang [], Mingliang Yue [], Huiting Wu [] and Yifan Xiao [], School of Earth Sciences, China University of Geosciences, 388 Lumo Road, Hongshan, Wuhan 430074, PR China.  相似文献   


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This work presents the preliminary results of studies conducted on pre-Hispanic pottery produced by the South American hunter–gatherer communities that inhabited the Paraná River lowlands during the Late Holocene. The data generated allow advancement of knowledge and discussion regarding the ceramic technologies employed by these groups, which have to date received little archaeological study. Specifically, technological and formal-functional analyses have been performed on a ceramic assemblage from the site of Cerro Puesto Acosta, located in the upper region of delta formed by this high-volume South American river in northeastern Argentina. Both macroscopic and microscopic aspects of these ceramics have been studied using archaeometric techniques (petrographic analysis). The patterns revealed by these analyses suggest the implementation of technological choices oriented towards the creation of vessels especially suitable for the processing, cooking, and serving of foods, which indicates the economic importance of these artifacts in allowing maximum advantage to be taken of the area’s available resources.  相似文献   

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Little detailed academic research has gone into the development of the English stage-coach system. With the exception of the work of such writers as Jackman, Dickinson, Hart and Bagwell,[1] the history of coaching has suffered from a surfeit of romantic and antiquarian writing[2] and a deficiency of close studies of the primary sources of information. The aim of this paper is to examine the development of a stage-coach system at a regional level—in South Hampshire—in the hope of throwing new light on the subject as a whole, and of contributing to a fuller understanding of the region's changing geography during the period.  相似文献   

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The marsh deer (Blastocerus dichotomus, Illiger, 1815) is the largest contemporary South American deer, and its habitat includes the floodplains and wetlands of eastern South America. Throughout the Holocene these deer were widely used by indigenous societies, from the southern banks of the Amazon River to the Río de la Plata River, and from the Andean foothills to the Atlantic Ocean. However, despite the enormous ecological and archaeological importance of this ungulate in the region, our knowledge of the isotopic values of their diet is almost nonexistent. This paper is the first systematic approach to the study of the isotopic values of this mammal's diet, using archaeological and present-day samples from interconnected watersheds of the Paraná and Uruguay rivers in east-central Argentina. The results obtained from 24 measurements indicate an average value of ?21.09 ± 1.46‰ in δ13C collagen, with a low coefficient of variation (6.92%). The data indicate a marked preference for consumption of plants with a C3 photosynthetic pathway. Most of the observed variability in the isotopic values corresponds to the period 900–1430 14C years BP, a time range during which the values show higher consumption of C4 plants. This it could be related with a period where temperature and associated humidity increased, synchronous in the area with the Medieval Climate Anomaly.  相似文献   

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New bird fossils from the Santa Cruz Formation (lower–middle Miocene), Santa Cruz Province, Patagonia, Argentina, are described. They represent an indeterminate species of the extinct anhingid Macranhinga and a new genus and species of basal Anatidae Ankonetta larriestrai. The record of the giant darter Macranhinga constitutes the southernmost record for the family, and expands the known stratigraphic range of the genus, previously restricted to the upper Miocene. Based on an analysis of the fossil anhingid record from South America, we hypothesize that giant darters disappeared from South America in the early Pliocene due to climatic deterioration, regression of marine and freshwater environments, the arrival of placental carnivorous mammals, and also probably by competition with phalacrocoracid cormorants. The new anatid Ankonetta is based on an incomplete but informative tarsometatarsus, with superficial similarities to extant Dendrocygna. A brief overview of several fossil ducks from the Patagonian Cenozoic concludes that most pre-Pliocene examples belong to non-anatine taxa, indicating that plesiomorphic ducks were the dominant anseriforms in those times, a pattern also evident on other continents.  相似文献   

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The international community has hailed South African state president, F.W. de Klerk, a ‘liberator’. De Klerk liberalised the political process and deracialised aspects of state and society. But how committed to racial reform are be and his government? The regime's policies, strategies and tactics over the last two years raise many concerns that the international community has either baulked or simply ignored. The argument that the government must be rewarded and encouraged is fallacious. The South African government reacts only to pressure. The international community acted prematurely by lifting some sanctions and is undermining the prospects for a post‐apartheid society based on equal rights.  相似文献   

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Abstract

The late pre-Hispanic populations of the Calchaquí Valley of NW Argentina may be seen as typical of the native culture of the south Andes. The developmental sequence for these sedentary village societies, however, has only recently begun to be detailed. Field and lab results pertaining to a survey of 24 sites are summarized, including one of the first ceramic seriations to include the full range of pottery types; ceramic wares and their significance are also identified. Findings further include the first recognition of what are believed to be Middle Period sites for the valley, thus filling an important gap in our understanding of the region's prehistory.  相似文献   

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Onary-Alves, S.Y., Hsiou, A.S. & Rincón, A.D., July 2016. The northernmost South American fossil record of Boa constrictor (Boidae, Boinae) from the Plio–Pleistocene of El Breal de Orocual (Venezuela). Alcheringa 41, xxx–xxx. ISSN 0311-5518.

Boa constrictor is an extant boid widely distributed through the neotropical region, from the north of Central America to central Argentina. The fossil record of the species includes examples from several localities across the Americas that extend beyond the current distribution of the species. Here we report the first Plio–Pleistocene fossils of Boa from Monagas state, Venezuela. The material comes from El Breal de Orocual (Maturín municipality), which is an inactive tar seep deposit emplaced within the Mesa Formation. The specimens consist of two isolated anterior trunk vertebrae, an articulated sequence of six mid-trunk vertebrae and two posterior trunk vertebrae. The vertebrae are attributed to B. constrictor based on the following features: robust and high vertebrae; thick zygosphene with a notched or concave anterior edge; presence of a paracotylar, subcentral and lateral foramina; marked parasagittal ridges; epizygapophyseal process evident on the dorsal surface of the postzygapophyseal articular facets and high blade-like neural spine. The presence of B. constrictor in northern of Venezuela indicates a palaeoenvironment probably like savanna crossed by rivers with riparian forests, and suggests the predominance of a mesothermal climate with a moderate rainfall.

Silvio Y. Onary-Alves [], Programa de Pós-graduação em Biologia Comparada, Faculdade de Filosofia, Ciências e Letras, Universidade de São Paulo (USP), Av. Bandeirantes 3900, CEP 14040901, Ribeirão Preto, São Paulo, Brazil; Annie S. Hsiou [], Laboratório de Paleontologia, Faculdade de Filosofia, Ciências e Letras, Departamento de Biologia, Universidade de São Paulo (USP), Av. Bandeirantes 3900, CEP 14040901, Ribeirão Preto, São Paulo, Brazil; Ascanio D. Rincón [], Laboratorio de Paleontología, Centro de Ecología, Instituto Venezolano de Investigaciones Científicas (IVIC), Carretera Panamericana Km 11, 1020-A Caracas, Venezuela.  相似文献   


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