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951.
952.
953.
3400 years of agricultural engineering in Mesoamerica: lama-bordos of the Mixteca Alta,Oaxaca, Mexico 总被引:1,自引:0,他引:1
The origins of early Mesoamerican agricultural techniques are not well established. Our charcoal-derived radiocarbon chronology dates cross-valley check dams, or lama-bordos, buried by up to 11.5 m of sediment in arroyos near Coixtlahuaca, Oaxaca, Mexico. Now it is clear that people in highland Mexico built lama-bordos at least 3400–3500 years ago, several hundred years earlier than previously dated engineering systems in Mesoamerica. Lama-bordo systems evolved as intensively and extensively managed landscapes coeval with climate shifting to more arid conditions. They provide clear examples of human-produced stratigraphy and artificial landscapes (stair-stepped valleys). More importantly, these lama-bordo systems signal a major cultural tipping point toward sedentary agricultural life and solidify our understanding of the Neolithic transition in Mesoamerica. 相似文献
954.
Johan Franzén 《The Journal of imperial and commonwealth history》2013,41(1):77-98
This study analyses British and local Iraqi elites’ efforts to avoid social revolution through promotion of economic development during the last years of the Iraqi monarchy. Discussing the complex set-up of domestic Iraqi elites and their ambiguous relations with British officials in Iraq, it argues that the structural composition of the Iraqi state itself is an important explanatory factor for the swift overthrow of the old regime in 1958. Using British archival records, this article analyses the politics of avoiding reform and promoting economic development to which Iraqi elites and the British were privy. It shows how economistic ideas of ‘modernisation’ and economic growth were believed to be the solution to Iraq's endemic problems of social unrest and politicisation of large parts of the population. Arguing that increased wealth through oil-fuelled development programmes would ultimately trickle down to all strata of the population and thus stave off the danger of revolution, the British failed to realise that Iraq's structural setup with its unscrupulous politicians and wealthy landowners at the apex of power, along with an all-permeating patronage system, effectively hampered any dispersal of what little new wealth was generated through these projects. 相似文献
955.
In Western Europe the transition from the Iron Age to the Roman period is the scene of a rapid economic and agro-pastoral evolution characterized in particular by a modification in the shape of the cattle. Understanding this phenomenon, its implementation mechanisms and development dynamics represents a major challenge in archaeozoology. In our study a local and regional approach of the evolution in cattle morphology is carried out first on the scale of the middle Seine valley, then of the northern Gaul. Its purpose is to observe and compare the evolution rates in domestic cattle between Middle La Tène and the fifth century AD, and with the help of a tight chronological and geographical grid, to estimate to what extent the shape of the cattle has been influenced by the indigenous cultures, the Roman economic pattern or even the environment. This osteometrical study is based on the Log Size Index method and on a measurement corpus of 12,969 bones collected on sites located on 117 communes in France (for most of them), Belgium, the Netherlands and Switzerland. The results we obtained show local specificities in terms of breeding methods and animal morphologies, observed on a very fine scale and taking place long before the Conquest. Moreover the growth patterns of the various herds happen to be different and to evolve under the impetus of the developing Roman economic pattern. This work thus points out an essential aspect of the agro-pastoral turmoil that took place in Gaul at the turning point of our era. The Roman pattern is not the cause of the morphological changes of the cattle, nor of the diversity in cattle shapes in Gaul, but it provokes a reshaping of the agricultural systems and a redefining of the breeding strategies which boost and completely change the cattle growth patterns. 相似文献
956.
957.
Dermal denticles of two thelodont agnathans, Australolepis seddoni gen. et sp. nov., and a possible nikoliviid gen. et sp. indet. are described from the Gneudna Formation, a marine sequence of interbedded limestone and shale exposed on the eastern edge of the Carnarvon Basin, Western Australia. The age and significance of these new forms are discussed. The Gneudna Formation is Late Devonian, probably early Frasnian, which, if confirmed, makes these the youngest thelodonts known to date. 相似文献
958.
Neil S. Davies Ivan J. Sansom Robert S. Nicoll Alex Ritchie 《Alcheringa: An Australasian Journal of Paleontology》2013,37(4):553-569
The Stairway Sandstone is a 30–560 m thick succession of Middle Ordovician siliciclastic sedimentary rocks within the Amadeus Basin of central Australia, deposited in the epeiric Larapintine Sea of northern peri-Gondwana. The Stairway Sandstone is significant as one of only two known Gondwanan successions to yield articulated arandaspid (pteraspidomorph agnathan) fish. Herein we use the ichnology of the Stairway Sandstone to reveal insights into the shallow marine habitat of these early vertebrates, and compare it with that of other known pteraspidomorph-bearing localities from across Gondwana. The Stairway Sandstone contains a diverse Ordovician ichnofauna including 22 ichnotaxa of Arenicolites, Arthrophycus, Asterosoma, Cruziana, Didymaulichnus, Diplichnites, Diplocraterion, ?Gordia, Lockeia, Monocraterion, Monomorphichnus, Phycodes, Planolites, Rusophycus, Skolithos and Uchirites. These ichnofauna provide a well-preserved example of a typical Ordovician epeiric sea assemblage, recording the diverse ethologies of tracemakers in a very shallow marine environment of flashy sediment accumulation and regularly shifting sandy substrates. New conodont data refine the age of the Stairway Sandstone to the early Darriwilian, with ichnostratigraphic implications for the Cruziana rugosa group and Arthrophycus alleghaniensis. 相似文献
959.
Arturo César Taboada Arthur J. Mory Guang-Rong Shi David W. Haig María Karina Pinilla 《Alcheringa: An Australasian Journal of Paleontology》2013,37(2):207-223
Taboada, A.C., Mory, A.J., Shi, G.R., Haig, D.W. & Pinilla, M.K., 12.11.2014. An Early Permian brachiopod–gastropod fauna from the Calytrix Formation, Barbwire Terrace, Canning Basin, Western Australia. Alcheringa 39, xxx–xxx. ISSN 0311-5518A small brachiopod–gastropod fauna from a core close to the base of the Calytrix Formation within the Grant Group includes the brachiopods Altiplecus decipiens (Hosking), Myodelthyrium dickinsi (Thomas), Brachythyrinella narsarhensis (Reed), Neochonetes (Sommeriella) obrieni Archbold, Tivertonia barbwirensis sp. nov. and the gastropod Peruvispira canningensis sp. nov. The fauna has affinities with that of the late Sakmarian?early Artinskian Nura Nura Member directly overlying the Grant Group in other parts of the basin but, as with all lower Cisuralian (and Pennsylvanian) glacial strata in Western Australia, its precise age remains poorly constrained, especially in terms of correlation to international stages. Although the Calytrix fauna lies within the Pseudoreticulatispora confluens Palynozone, the only real constraint on its age (and that of the associated glacially influenced strata) is from Sakmarian (Sterlitamakian) and stratigraphically younger faunas. A brief review of radiometric ages from correlative strata elsewhere in Gondwana shows that those ages need to be updated. The presence of Asselian strata and the position of the Carboniferous?Permian boundary remain unclear in Western Australia.Arturo César Taboada [ataboada@unpata. edu. ar], CONICET-Laboratorio de Investigaciones en Evolución y Biodiversidad (LIEB), Facultad de Ciencias Naturales, Sede Esquel, Universidad Nacional de la Patagonia ‘San Juan Bosco’, Edificio de Aulas, Ruta Nacional 259, km. 16,5, Esquel U9200, Chubut, Argentina; Arthur Mory [arthur. mory@dmp. wa. gov. au], Geological Survey of Western Australia, 100 Plain Street, East Perth, WA 6004, School of Earth and Environment, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia; Guang R. Shi [grshi@deakin. edu. au], School of Life and Environmental Sciences, Deakin University, Melbourne Burwood Campus, 221 Burwood Highway, Burwood, Victoria 3125, Australia; David W. Haig [david. haig@uwa. edu. au], School of Earth and Environment (M004), The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia; María Karina Pinilla [mkpinilla@fcnym. unlp. edu. ar], División Paleozoología Invertebrados, Museo de Ciencias Naturales de La Plata, Paseo del Bosque s/n, 1900 La Plata, Buenos Aires, Argentina. 相似文献
960.
Alberto Luis Cione Jose Herminio Laza Inés César 《Alcheringa: An Australasian Journal of Paleontology》2013,37(4):433-454
Several traces of biological interaction were found on penguin bones from the basal levels (Aquitanian) of the Miocene Gaiman Formation in the lower Chubut valley of the Provincia del Chubut, Argentina. The fossil-bearing beds were deposited in littoral to sublittoral environments within sediments of mostly pyroclastic origin. We interpret many traces to have been produced by predators and/or scavengers while the penguins were still in a breeding area. Many bones show cracking marks due to aerial exposure. The material is disarticulated as is usual in recent breeding areas. Potential predators were coeval terrestrial mammals, most probably marsupial carnivores. After a marine transgression, these bones were buried or exposed on the sea bottom where they could be colonized by algae, sponges, cnidarians, and other benthic organisms. We identified sponge borings in several bones. Other traces are interpreted to have been produced by echinoderms feeding on sponges or algae. No evidence of other invertebrate predators such as muricid or naticid gastropods, or decapods was found. Finally, other traces appear to have been generated by shark and possibly teleostean vertebrates feeding on epibionts. One coracoid is interpreted to have been marked by a shark that is common in the Gaiman Formation, the carcharhiniform Galeocerdo aduncus. From an ethological (Seilacherian) classification, traces on bones from the Gaiman Formation include Domichnia (sponge perforations), Praedichnia (terrestrial marsupials, sharks, teleosteans) and Pasichnia (echinoderms). Remarkably, remains of marine organisms with skeletons made of calcium carbonate are very poorly preserved in the Gaiman Formation. Only large oysters, sparse shell fragments, skeletal moulds, and bioturbation is evident. The fossil assemblage is mainly composed of phosphatic (e.g. teeth, bones, crustacean parts) and siliceous (sponge spicules, diatoms) remains. 相似文献