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51.
Abstract

On archaeological sites where livestock dung was a major fuel source, plant material that survives digestion intact may well be preserved in the remnants of dung-fuelled fires. Preserved plant remains which were derived from dung relate to the diet of animals, and thus provide a way of investigating the agro-pastoral economies of the past. In order to improve our understanding of the taphonomic processes to which plant material is exposed to during digestion, we applied archaeobotanical methods to the analysis of dung from sheep fed a known diet of cereal and wild plant material. Two clear patterns emerge from these investigations. First, cereal material (grain or chaff) survives digestion poorly and was rarely found in the dung analysed. Second, large proportions of seeds of various wild species survive digestion in an identifiable form, probably due to their small size and/or protective coating. These findings are crucial for reliable interpretation of dung-derived plant material in archaeological settings.  相似文献   
52.
Although carbon-14 dates prior to 13,000 B.P. have been obtained from several sites east and south of Amazonia, their reliability is uncertain. By about 11,000 B.P., however, two lithic traditions were widespread. The Uruguai tradition, characterized by bifacial stemmed projectile points, was associated with open vegetation in the south; the Itaparica tradition, emphasizing well-formed unifacial artifacts, had dispersed over the eastern tropical parklands. An enormous amount and variety of rock paintings and/or engravings are associated with the latter. Around 7000 B.P., two new traditions emerged to exploit new habitats. The Humaitá tradition, characterized by large bifacial tools and an absence of stone projectile points, expanded over the broad-leaved forests in the south, leaving the open landscapes dominated by the projectile point-using Umbu tradition. The sambaqui (shell midden) tradition, also emphasizing large bifaces, developed along rugged portions of the southern coast. By 4000 B.P., groups along the coast of Rio de Janeiro and Espírito Santo were using domesticated or semidomesticated plants, perhaps sweet manioc. Maize was being grown in Minas Gerais by about 3500 B.P. Carbon-14 dates from numerous sites indicate, however, that the hunter-gatherer way of life persisted in many places long after the advent of pottery-making horticulturalists. The existence of large temporal and spatial gaps even in regions with considerable investigation makes it difficult to reconstruct the process of evolution reflected in these archaeological complexes. Correlations between cultural traditions and environmental fluctuations indicate, however, that adaptation to changing conditions was a significant challenge faced by prehistoric Brazilian populations.  相似文献   
53.
Several small seeded plants were domesticated as grain crops in the Near East and other domestication centers. In this study we investigate the potential of small seeded wild lentils, and chickpea as a food source for hunters-gatherers. The yield potential and the return in terms of grams of seeds per hour of collection time were evaluated in several wild populations in Israel. The yield figures never exceeded 50 g/h, and in most cases were below 20 g/h. These data reaffirm Ladizinsky's claim that wild lentils are unlikely to have been a staple resource for hunter-gatherers prior to plant domestication. The result presented herein may be significant vis-a-vis the role attributed to small seeded (‘inefficient’) plants in the Broad Spectrum hypothesis concerning late Paleolithic, pre-agricultural societies. It may also contribute to a more careful interpretation of plant remains recovered from pre-agricultural sites.  相似文献   
54.
Phylogenetic techniques are used to analyse the spread of Neolithic plant economies from the Near East to northwest Europe as a branching process from a founding ancestor. The analyses are based on a database of c. 7500 records of plant taxa from 250 sites dated to the early Neolithic of the region in which they occur, aggregated into a number of regional groups. The analysis demonstrates that a phylogenetic signal exists in the data but it is complicated by the fact that in comparison with the changes that occurred when the crop agriculture complex expanded out of the Near East, once it arrived in Europe it underwent only limited further changes. On the basis of the analysis it has been possible to identify the species losses and gains that occurred as the complex of crops and associated weeds spread and to show the influence of geographical location and cultural affinity on the pattern of losses and gains. This has led to consideration of the processes producing that history, including some reasons why the dispersal process did not produce a perfect tree phylogeny, as well as to the identification of some specific anomalies, such as the unusual nature of the Bulgarian pattern, which raise further questions for the future.  相似文献   
55.
Previous evaluations of the potential advantage of farming over foraging have been based on experimental harvesting of wild cereals in Near Eastern ecosystems. The highly successful combination of cereals and legumes, “the Near Eastern crops assemblage”, is considered a natural choice due to the complementary nutritional value of the two crop types. Yet, legumes were rarely referred to in models describing early farming and the transition from foraging to farming. Wild legumes differ from wild cereals in several attributes pertaining to domestication, including population density (patchy vs. dense), growth habit (indeterminate vs. determinate), dispersal units (camouflaged seeds vs. awned spikelets), seed dormancy (90–80% vs. 50%), and year to year establishment (erratic vs. regular). We have analyzed the yield potential of three wild pea species (Pisum elatius, P. humile, and P. fulvum) in several ecosystems in Israel. All three pea species have patchy distribution patterns and the yield potential of the wild populations is highly variable. A harvest rate of 0.6–610 grams (calculated per collector) of clean dry grain per hour of harvest time was estimated. Among the three species studied the one adopted for domestication appears to be the least productive. This suggests that the potential productivity of wild peas was not the only or even the major consideration for domestication.  相似文献   
56.
Hypolithic plants, plants growing under rocks, have been found from a number of climatically extreme, mostly arid sites from the poles to the equator, but there are limited reports from temperate zones. A brief survey in the Kosciuszko Alpine Area of New South Wales, Australia, revealed four species of moss and one liverwort growing beneath diaphanous quartz pebbles in feldmark vegetation communities. The probable restricted nature of this phenomenon and the likely impact of global warming, tourists and recreation management activities raise concerns for its conservation.  相似文献   
57.
Archaeological research since 1988 in West Africa has focused almost exclusively on the period since 10,000 B.P. Significant advances have been made in our understanding of the Late Stone Age in the Sahara and Savanna zones, the advent of metallurgy and subsequent changes in metal technology, and the comparative trajectories of complex societies in different regions. Increasingly, data are being recovered that fail to conform to earlier Eurocentric assumptions emphasizing linear, progressive change through a series of evolutionary ages and stages. The search for new, more appropriate models for interpreting West Africa's past has infused the discipline with great theoretical vitality. Both ethnoarchaeological studies and traditional archaeological research programs in West Africa are contributing substantially to the articulation of new theoretical frameworks for African archaeology and potentially for the discipline as a whole.  相似文献   
58.
Palaeoecological and geoarchaeological investigations which cover the Anglo-Saxon period are rare, particularly in chalk downland landscapes which are considered to have limited palaeoenvironmental potential. The present study explores a sequence which can be directly related to the occupation history of the major Anglo-Saxon settlement at Lyminge, Kent. This work demonstrated a sequence of palaeochannels and organic deposits associated with the latter part of an archaeological sequence which spans the 5th to the 11th centuries AD. A range of evidence for the environment and economic activity is presented which suggests landscape continuity, possibly stretching back as far as the Romano-British period. The sequence revealed worked wood and evidence for livestock management and cereal cultivation, some of which is contemporary with the final phases of occupation of a 7th century ‘great hall complex’ and its subsequent transformation into a royal monastery. Agricultural activity following the abandonment of the pre-monastic settlement area caused this stream margin to become gradually buried by ploughwash which displaced the channel over time and sealed the organic deposits. It is incredibly rare to find such organic preservation in direct association with an Anglo-Saxon downland rural settlement and this is the first time that such a sequence has been analysed in association with the latter phases of a known Anglo-Saxon royal and monastic centre.  相似文献   
59.
Late Archaic archaeobotanical remains from the County Home site (33AT40), southeastern Ohio, are described. Measurements of chenopod (Chenopodium berlandieri) seed-coat thicknesses and marshelder (Iva annua) achene and kernel lengths from the site are indicative of domesticated types (ssp. jonesianum and var. macrocarpa, respectively) dating to ca. 3000 B.P. to 3600 B.P. Together, these specimens represent some of the earliest evidence of plant domestication outside the oak-hickory and oak-savannah forests of eastern North America. The recovery of these plants with other cultigens in hearths and earth ovens at the County Home site indicates that the timing for the arrival of the Initial Crop Complex in the Appalachian mixed forest of the middle Ohio Valley occurred earlier than previously documented. The results of this research contribute to the growing database of early plant domestication and a broader understanding of the origins of food production.  相似文献   
60.
In Australia, the largest importer of exotic plant species is the gardening industry, and most major environmental weeds originally derive from domestic gardens or nurseries. To provide strategies for weed management, this study aims to clarify two key points on the pathway along which garden plants flow from the market to the natural environment with the help of human activities. These are local residents' procurement of garden plants, and local residents' garden‐related behaviour (e.g. leaving organic materials in reserves). We draw on a survey (382 respondents) among Wollongong (New South Wales, Australia) residents whose property has at least one boundary adjacent to bushland. Frequency analysis and ordinal regression were used. The results indicated that most respondents obtained garden plants, and relevant information, from nurseries but perceived that there was insufficient plant origin information (that is, whether introduced from abroad, native to Australia or local to the Illawarra) to help them make choices. It also indicated that a minority of respondents frequently left organic materials (such as lawn clippings) in reserves neighbouring their garden, and many of these respondents saw some benefits in doing so. This study confirms the significant role of nurseries in gardeners' plant choice, and raises questions about the significance of dumping garden waste.  相似文献   
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