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A thorough review concerning palm uses in tropical rainforests of north-western South America was carried out to understand patterns of palm use throughout ecoregions (Amazonia, Andes, Chocó), countries (Colombia, Ecuador, Peru, Bolivia), and among the different human groups (indigenous, mestizos, afroamericans, colonos) that occur there. A total of 194 useful palm species, 2,395 different uses and 6,141 use-reports were recorded from 255 references. The Amazon had the highest palm use, whereas fewer, but similar uses were recorded for the Andes and Chocó. Ecuador was the most intensively studied country. Most palms were used for human food, utensils and tools, construction, and cultural purposes. Indigenous people knew more palm uses than mestizos, afroamericans and colonos. The use of palms was not random and the main uses were the same throughout the studied ecoregions and countries. Palms satisfy basic subsistence needs and have great importance in traditional cultures of rural indigenous and peasant populations in our study area. Arecaceae is probably the most important plant family in the Neotropics, in relation to use diversity and abundance.  相似文献   

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Species richness patterns of tiger beetles (Coleoptera: Cicindelidae) were analyzed using a grid of 407 squares (137.5 km per side) across northwestern South America (Guyana, Venezuela, Colombia, Ecuador, Peru, Bolivia and western Brazil). Reliable data on species numbers were available for only 149 of the squares. Using a trend surface model (a model used to represent the mean of a spatial process by a polynomial function of spatial coordinates) as well as altitudinal relief and biogeographical influence for each square, we predicted the number of tiger beetle species likely to occur in intermediate squares for which no or unreliable data were available. The resultant spatial patterns of species richness were compared to similar analyses for temperate areas of North America. Intercontinental comparisons and a more complete pattern of species numbers in South America are useful in developing an understanding of general spatial patterns and in the environmental management of species richness.  相似文献   

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Background

The global spread of HIV-1 has been accompanied by the emergence of genetically distinct viral strains. Over the past two decades subtype C viruses, which predominate in Southern and Eastern Africa, have spread rapidly throughout parts of South America. Phylogenetic studies indicate that subtype C viruses were introduced to South America through a single founder event that occurred in Southern Brazil. However, the external route via which subtype C viruses spread to the South American continent has remained unclear.

Methodology/Principal Findings

We used automated genotyping to screen 8,309 HIV-1 subtype C pol gene sequences sampled within the UK for isolates genetically linked to the subtype C epidemic in South America. Maximum likelihood and Bayesian approaches were used to explore the phylogenetic relationships between 54 sequences identified in this screen, and a set of globally sampled subtype C reference sequences. Phylogenetic trees disclosed a robustly supported relationship between sequences from Brazil, the UK and East Africa. A monophyletic cluster comprised exclusively of sequences from the UK and Brazil was identified and dated to approximately the early 1980s using a Bayesian coalescent-based method. A sub-cluster of 27 sequences isolated from homosexual men of UK origin was also identified and dated to the early 1990s.

Conclusions

Phylogenetic, demographic and temporal data support the conclusion that the UK was a crucial staging post in the spread of subtype C from East Africa to South America. This unexpected finding demonstrates the role of diffuse international networks in the global spread of HIV-1 infection, and the utility of globally sampled viral sequence data in revealing these networks. Additionally, we show that subtype C viruses are spreading within the UK amongst men who have sex with men.  相似文献   

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In native South America, ceremonial dialogue is a widespread and prominent, yet simultaneously enigmatic, form of ritualized language use. This paper examines the ceremonial dialogic complex through the interpretive lens of a semiotic hypothesis, namely, that ritualized dialogic form is a sign vehicle, a "model of and for" linguistic and more generally social solidarity. A comparative correlational study confirms this semiotic interpretation, showing that the ceremonial dialogue is used in situations of potential conflict—the maximally distant social relations within a given society. This paper also raises a broader theoretical issue concerning the role of metacommunicative devices in social action, suggesting that it is the "meta-signal" itself that enables actors to formulate an image of action—thereby regulating it—simultaneously as it occurs.  相似文献   

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We reviewed information on management of useful palms in South America. We documented management for 96 species, from incidental activities intended to increase populations of wild palms to the inclusion of palms in complex agroforestry systems. Two species, Bactris gasipaes and Parajubaea cocoides, are domesticated. Managed species are remarkably fewer than species used in the region, which suggests that harvesters often disregard the fate of the species they use. The best way of managing palms is to employ harvest methods that do not decimate the populations. Although a variety of harvesting techniques have been documented, overharvest is common, and mismanagement prevails – unnecessary felling of palms in order to harvest leaves or fruits is a widespread practice. Research should focus on assessing production in response to management practices, but eradicating the habit of destructive harvest is an obvious priority. Research on palm management must be combined with actions addressed to all stakeholders of the palm/humans system.  相似文献   

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Ethnobotanical field studies were conducted for the first time in the KwaNibela Peninsula of southern Maputaland, KwaZulu-Natal, to document indigenous knowledge about useful plants. The vernacular names and uses of 82 plant species were recorded and compared to published Zulu and Swazi knowledge. Medicines for skin disorders, toothache, wounds, worms, chest and throat ailments, infertility and purgatives are still commonly used. Superstition and divination play a major role in the traditional knowledge system of the people of KwaNibela with 24 plants used for this purpose. Three KwaNibela medicinal plants (Erythroxylum delagoense, Putterlickia verrucosa, and Teclea natalensis) appear to be new records, not previously reported in the general scientific literature. The list also includes 61 novel uses of plants and another 15 new variations on known (published) uses. Ten previously unpublished vernacular names are presented, together with an additional 19 new variants of known names. These new additions to the scientific literature confirm that indigenous knowledge in KwaZulu-Natal is not yet completely recorded.  相似文献   

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The quest for the origin and dispersion of Chagas' disease, the second most important vector-borne disease in Latin America, has epidemiological, immunological, and genetical implications. Conjectures based on accounts of chroniclers, reviews of the archaeological literature and the present distribution of triatomine bugs, the vectors of the disease, held that the origin of the adaptation of Triatoma infestans (aspecies of the subfamily Triatominae) to human dwellings occurred in prehistoric times. The autopsy of 35 mummies exhumed in the Chilean desert, dated between 470 B.C. and 600 A.D., revealed the presence of clinical manifestations of Chagas' disease and put earlier speculations on a factual basis.  相似文献   

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Desiccation tolerant plants in South America   总被引:7,自引:0,他引:7  
D. F. Gaff 《Oecologia》1987,74(1):133-136
Summary Numerous Velloziaceae species concentrated in Minas Gerais, Brazil, constitute most of the desiccation tolerant flora of S. America. In the grasses, two Microchloa spp and Tripogon spicatus are desiccation tolerant. Though widespread, they are low growing and appear unimportant. With the exception of Anemia, desiccation tolerant ferns in dry land areas are related to the resurrection fern flora reported for N. America. The likely possibility of a desiccation tolerant flora of epiphytic ferns in rain forest areas was not investigated.  相似文献   

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