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1.
Field experiments with transgenic plants often reveal the functional significance of genetic traits that are important for the performance of the plants in their natural environments. Until now, only constitutive overexpression, ectopic expression and gene silencing methods have been used to analyze gene‐related phenotypes in natural habitats. These methods do not allow sufficient control over gene expression for the study of ecological interactions in real time, of genetic traits that play essential roles in development, or of dose‐dependent effects. We applied the sensitive dexamethasone (DEX)‐inducible pOp6/LhGR expression system to the ecological model plant Nicotiana attenuata and established a lanolin‐based DEX application method to facilitate ectopic gene expression and RNA interference‐mediated gene silencing in the field and under challenging conditions (e.g. high temperature, wind and UV radiation). Fully established field‐grown plants were used to silence phytoene desaturase and thereby cause photobleaching only in specific plant sectors, and to activate expression of the cytokinin (CK) biosynthesis gene isopentenyl transferase (ipt). We used ipt expression to analyze the role of CKs in both the glasshouse and the field to understand resistance to the native herbivore Tupiocoris notatus, which attacks plants at small spatial scales. By spatially restricting ipt expression and elevating CK levels in single leaves, damage by T. notatus increased, demonstrating the role of CKs in this plant–herbivore interaction at a small scale. As the arena of most ecological interactions is highly constrained in time and space, these tools will advance the genetic analysis of dynamic traits that matter for plant performance in nature.  相似文献   
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New social media have become indispensable to people all over the world as platforms for communication, with Facebook being the most popular. Hence, platforms such as Facebook are also becoming crucial tools for ethnographers because much social life now exists ‘online’. What types of field relations stem from such social media-driven ethnography? And what kinds of data do these relations present to the ethnographer? These questions must be considered in order to understand the challenges Facebook and other social media pose to ethnographic methodology. This article focuses on how Facebook may play an important role even in ethnographic work concerned with questions other than how Facebook works as a social medium. Most importantly it allows the ethnographer to keep up-to-date with the field. I argue that ethnography is already in possession of the methodological tools critically to assess the validity and value of data gathered or produced via Facebook including issues such as authenticity which are also pertinent to digital ethnography.  相似文献   
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With approximately 30% of nonhuman primate species listed as critically endangered, the window of opportunity to conserve primates is closing fast. In this article, we focus on the degree to which publications in field primatology are biased in favor of particular taxa and field sites. We examined more than 29,000 peer‐reviewed articles and identified 876 field visits to 349 field sites. We found a highly clumped distribution by site and species. We also examined publication ethical statements and the extent to which they acknowledged local human communities (<5%). Due to a lack of consistency across publications, we provide recommendations for improving ethical statements and for evaluating research impact. Given the plight of primate biodiversity, these results suggest broader coverage of primate species and geographies, as well as more attention to the local human communities whose support is necessary if the intent is to have primate species in the wild in the 22nd century.  相似文献   
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Ethnographic films hold great historical value for the communities in which they were filmed, yet people in source communities often lack access to them. Visitors engaging in ‘visual repatriation’ of ethnographic film can enrich both sides of the ethnographic exchange. I review my experiences screening ethnographic films with Trobriand Islanders, their reactions, and the various ways in which local communities regain ownership of these films, including re‐narration and renaming. My findings reiterate how source communities' reception of, and uses for, ethnographic film can sharply differ from the filmmakers' original agenda.  相似文献   
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This paper compares and contrasts three groups that conducted biological research at Yale University during overlapping periods between 1910 and 1970. Yale University proved important as a site for this research. The leaders of these groups were Ross Granville Harrison, Grace E. Pickford, and G. Evelyn Hutchinson, and their members included both graduate students and more experienced scientists. All produced innovative research, including the opening of new subfields in embryology, endocrinology and ecology respectively, over a long period of time. Harrison's is shown to have been a classic research school; Pickford's and Hutchinson's were not. Pickford's group was successful in spite of her lack of department or institutional position or power. Hutchinson and his graduate and post-graduate students were extremely productive but in diverse areas of ecology. His group did not have one focused area of research or use one set of research tools. The paper concludes that new models for research groups are needed, especially for those, like Hutchinson's, that included much field research.  相似文献   
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Here we assessed the efficacy of performing field surveys during both dry and rainy seasons to estimate species richness and composition of phyllostomid bats in 12 sites of the Brazilian Atlantic Forest. Our goal was to elucidate two opposite scenarios. If bat species compositions differ between the dry and rainy seasons, then field surveys in both seasons will be considered complementary for estimating local bat assemblages. In contrast, if bat species compositions in the dry season are a nested subset of the species present in the rainy season, then field surveys in both seasons will be considered redundant. Our results showed that field surveys performed only during the rainy season exhibited the same efficacy in recording bat species as field surveys considering both dry and rainy seasons combined. Consequently, the rare species sampled in the rainy season contributed to the uniqueness of communities in terms of species composition. Considering that time, funding, and the number of field personnel available for work are important factors when determining the sampling effort in highly biodiverse regions like the tropics, our results can be useful in establishing protocols for research projects with limited resources aiming to create a comprehensive list of species.  相似文献   
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Erica Bornstein 《Ethnos》2013,78(4):483-508
Focusing on the idea of dwelling in the field, this paper explores the moral grammar of living with others in field settings, including the texture of membership in one's own family and host families. Through a comparative analysis of two ethnographic research contexts – one on transnational Christian non-governmental organizations in the US and Zimbabwe in 1996 –97, and the other on orphans and philanthropy in India in 2004–05 – I interrogate what it means to inhabit the field. In the world of multi-sited ethnography all research sites are not created equal; both in terms of the kinds of data one can collect and the types of observations one can make. How ethnographers are situated in a web of affliations affects their experience in the field, what they observe, and their research practice. I propose renewed attention to how anthropologists live in the field, including how relationships are interpreted in the field by ethnographers and their informants.  相似文献   
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