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Multidisciplinary investigations at Kuk Swamp in the Highlands of Papua New Guinea show that agriculture arose independently in New Guinea by at least 6950 to 6440 calibrated years before the present (cal yr B.P.). Plant exploitation and some cultivation occurred on the wetland margin at 10,220 to 9910 cal yr B.P. (phase 1), mounding cultivation began by 6950 to 6440 cal yr B.P. (phase 2), and ditched cultivation began by 4350 to 3980 cal yr B.P. (phase 3). Clearance of lower montane rainforests began in the early Holocene, with modification to grassland at 6950 to 6440 cal yr B.P. Taro (Colocasia esculenta) was utilized in the early Holocene, and bananas (Musa spp.) were intensively cultivated by at least 6950 to 6440 cal yr B.P.  相似文献   

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Africa: cradle of modern humans   总被引:2,自引:0,他引:2  
R Lewin 《Science (New York, N.Y.)》1987,237(4820):1292-1295
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The concepts by which MacArthur and Wilson have transformed the science of ecology in the past decade, and the results of ecological studies such as mine on New Guinea bird communities, have implications for conservation policies. For example, primary tropical rain forest, the most species-rich and ecologically complex habitat on earth, has for millions of years served as the ultimate evolutionary source of the world's dominant plant and animal groups. Throughout the tropics today, the rain forests are being destroyed at a rate such that little will be left in a few decades. When the rain forests have been reduced to isolated tracts separated by open country, the distribution of obligate rain forest species will come to resemble bird distributions on New Guinea land-bridge islands after severing of the land bridges. The smaller the tract, the more rapidly will forest species tend to disappear and be replaced by the widespread second-growth species that least need protection (13). This ominous process is illustrated by Barro Colorado Island, a former hill in Panama that became an island when construction of the Panama Canal flooded surrounding valleys to create Gatun Lake. In the succeeding 60 years several forest bird species have already disappeared from Barro Colorado and been unable to recolonize across the short intervening water gap from the forest on the nearby shore of Gatun Lake. The consequences of the species-area relation (Fig. 1) should be taken into consideration during the planning of tropical rain forest parks (13). In a geographical area that is relatively homogeneous with regard to the fauna, one large park would be preferable to an equivalent area in the form of several smaller parks. Continuous nonforest strips through the park (for example, wide highway swaths) would convert one rain forest "island" into two half-size islands and should be avoided. If other considerations require that an area be divided into several small parks, connecting them by forest corridors might significantly improve their conservation function at little further cost in land withdrawn from development. Modern ecological studies may also be relevant to the understanding of human populations. For instance, during a long period of human evolution there appear to have been not one but two coexistent hominid lines in Africa, the Australopithecus robustus-A. boisei ("Zinjanthropus") line, which became extinct, and the Australopithecus africanus-A. habilis line, which led to Homo sapiens (27). The need to maintain niche differences between these lines must have provided one of the most important selective pressures on the ancestors of modern man in the late Pliocene and early Pleistocene. Thus, any attempt to understand human evolution must confront the problem of what these ecological segregating mechanisms were. To what extent were contemporaneous species of the two lines separated by habitat, by diet, by size difference, or by foraging technique, and were their local spatial distributions broadly overlapping or else sharpened by behavioral interactions as in the case of the Crateroscelis warblers of Fig. 6? To take another example, there are striking parallels between the present distributions of human populations and of bird populations on the islands of Vitiaz and Dampier straits between New Guinea and New Britain. Some of these islands were sterilized by cataclysmic volcanic explosions within the last several centuries. The birds that recolonized these islands have been characterized as coastal and small-island specialists of high reproductive potential, high dispersal powers, and low competitive ability, unlike the geographically closer, competitively superior, slowly dispersing, and breeding birds of mainland New Guinea (10, 11, 13). It remains to be seen whether the people of the Vitiaz-Dampier islands, the Polynesians, and other human populations that colonize insular or unstable habitats also have distinctive population ecologies.  相似文献   

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Six examples of a variation in the LDH-A subunit have been detected in 408 samples from three exogamous clans in the New Guinea Highlands. The New Guinea variant is similar to the Memphis-4 variant. Origin of the New Guinea variant could not be traced by genealogy but it seems likely to have persisted for several generations.  相似文献   

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"佳娃"系列是新几内亚凤仙中理想的4寸(10cm)盆栽品种.该系列具有分枝性好,花朵繁茂,植株紧溱;整齐性好等优点.该系列开花一致性好,整个系列的开花时间相差不超过1周.该系列穴盘苗生产,具有栽培周期短,生产投入低,适于机械移植等优势.本文就"佳娃"系列栽培技术进行总结.  相似文献   

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影视人类学在我国起步虽晚但发展较快.其研究路径存在较大差别.本文分析了“影视”和“人类学”两种研究路径,认为《影视人类学理论探究》一书为我们描述了“影视”研究路径得到的结果,却没有回答“人类学”或“视觉”研究路径会得到什么.因此期待更多研究者的参与.  相似文献   

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Analysis of the hereditary Gm and Inv gamma-globulin factors of 1669 New Guineans from the Morobe and Eastern Highlands districts and Bougainville Island demonstrates thatthe frequencies of the three Gm alleles present (Gm(a), GM(ab), and Gm(ax)) are similar in general to those in Mongoloids and in particular to those in Southeast Asians and Micronesians. The New Guinea frequencies are distinct from those in other populations, including Australian aborigines. Highly significant differences in frequencies of Gm and Inv alleles occur between Melanesian-and non-Austronesian-speaking New Guineans.  相似文献   

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