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Geographic Boundaries (geographic + boundary)
Selected AbstractsPair Duets in the Yellow-Naped Amazon (Psittaciformes: Amazona auropalliata): Responses to Playbacks of Different DialectsETHOLOGY, Issue 2 2001Timothy F. Wright Yellow-naped amazons, Amazona auropalliata, have regional dialects in which several functional classes of vocalization, including contact calls and pair duets, change their acoustic structure at the same geographic boundaries. Here we examine the responses of 11 pairs of yellow-naped amazons to playbacks of duets from other pairs nesting near the same roost, other roosts within the same dialect, and roosts in foreign dialect areas. Overall, pairs responded more strongly to duets from their own dialect than to those of the foreign dialect. Pairs responded to both treatments from their own dialect (local same dialect and distant same dialect) with movement towards the broadcasting loudspeaker and more rarely with squeals, a vocalization typically observed only in the context of aggressive chases. These aggressive responses were never observed during playbacks of the foreign dialect treatment or congeneric controls. There were no differences among treatments in the incidence of contact calls or pair duets. A similar pattern of stronger aggressive responses to local than to foreign dialects has been found in a wide range of oscine songbirds. The results of the present experiment suggest that a general function may underlie this behavioral response both in oscines and in other bird taxa with vocal learning. [source] URBAN CLUSTERS AS GROWTH FOCI,JOURNAL OF REGIONAL SCIENCE, Issue 2 2009Boris A. Portnov ABSTRACT Urban clusters are geographic concentrations of urban places, some of which may include major cities. Unlike agglomerations, whose geographic boundaries are clearly delineated, urban clusters have "variable" boundaries, with each urban settlement being part of its "own" cluster of populated places, located within its commuting range. As our study indicates, the effect of clustering on urban growth is not uniform: it appears to be positive in low density clusters, and negative in densely populated ones. In particular, outside densely populated areas, towns surrounded by other localities tend to evince higher rates of population growth than their "lone" counterparts. [source] Toward a model of the everyday life information needs of urban teenagers, Part 2: Empirical modelJOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 11 2006Denise E. Agosto This is the second part of a two-part article that presents a theoretical and an empirical model of the everyday life information needs of urban teenagers. Part 2 focuses on the derivation of the empirical model and on its relationship to the theoretical model presented in Part 1. Part 2 also provides examples from the project data to support each of the components of the empirical model, which ties 28 information needs topics to the seven independent variables in the theoretical model. Comparison of the empirical model to the results of past youth information behavior research shows that the participants in this study tended to have the same types of information needs as previous researchers have found with more advantaged, nonminority groups of teens. This finding is significant because it suggests that teenagers have similar information needs across socioeconomic, ethnic, cultural, and geographic boundaries. Due to the exploratory nature of this study, however, additional research is necessary to confirm this possibility. [source] Wissens- und Wissenschaftstransfer , Einführende Bemerkungen,BERICHTE ZUR WISSENSCHAFTSGESCHICHTE, Issue 3 2006Mitchell G. Ash Migration; Wissenschaftstransfer; Wissenschaftswandel; Wissenstransfer. Abstract Knowledge and science transfer , introductory remarks. The article presents introductory remarks on the historical study of knowledge and science transfer. Discussion focuses initially on the reasons for speaking of knowledge transfer and not only about science transfer, and the relations of this topic to current research in general history on cultural transfer. Multiple levels of knowledge / science transfer are then discussed, specifically: (1) transfer by means of migration or other movement of people across geographic boundaries; (2) scientific changes related to the transfer of objects (such as plant specimens or instruments) across continents or disciplines; (3) knowledge or science transfer in practical contexts. Addressed throughout is the problematic character of the concept of transfer itself. The author suggests that users of this concept often presuppose a static conception of scientific and cultural contents being more or less successfully transferred; more interesting, however, are the changes in science and culture conditioned or caused by the migration of individuals as well as the transfer of culture by other means. [source] Isolation and high genetic diversity in dwarf mountain toads (Capensibufo) from South AfricaBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 4 2010KRYSTAL A. TOLLEY Traditional models of amphibian dispersal and gene flow point to low dispersal and high philopatry. In recent years, this traditional view has been challenged and it appears that no general model holds across taxa. Conservation of amphibians cannot be addressed on an over-arching scale, but must come on a case-by-case basis, especially for range-restricted species where information on gene flow and migration must be incorporated into conservation efforts. The only two members of the genus Capensibufo Grandison, 1980 (Anura: Bufonidae) are range restricted small bufonids, with distributions limited to montane areas in South Africa. Using a Bayesian analysis of two mitochondrial markers (16S and ND2), we examined the genetic patterns in Capensibufo rosei and Capensibufo tradouwi in order to understand both taxonomic and geographic boundaries. These species were not monophyletic, and demonstrate no clear taxonomic boundaries. Instead, the genus is extremely diverse genetically, with distinct lineages confined to isolated mountains that represent geographic boundaries. In addition, bioclimatic modelling using MAXENT and scenarios of climatic conditions at both the present and last glacial maximum suggest multiple bioclimatic and physical barriers to gene flow at present and in the past. We conclude that members of the genus have very low vagility, that current taxonomic boundaries are inadequate, and that strong geographic structuring has undoubtedly contributed to genetic diversity at the species level, rather than the population level. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 100, 822,834. [source] Regional Monopoly and Interregional and Intraregional Competition: The Parallel Trade in Coca-Cola Between Shanghai and Hangzhou in ChinaECONOMIC GEOGRAPHY, Issue 1 2006Godfrey Yeung Abstract: This article uses a "principal-agent-subagent" analytical framework and data that were collected from field surveys in China to (1) investigate the nature and causes of the parallel trade in Coca-Cola between Shanghai and Hangzhou and (2) assess the geographic and theoretical implications for the regional monopolies that have been artificially created by Coca-Cola in China. The parallel trade in Coca-Cola is sustained by its intraregional rivalry with Pepsi-Cola in Shanghai, where Coca-Cola (China) (the principal) seeks to maximize its share of the Shanghai soft-drinks market. This goal effectively supersedes the market-division strategy of Coca-Cola (China), since the gap in wholesale prices between the Shanghai and Hangzhou markets is higher than the transaction costs of engaging in parallel trade. The exclusive distributor of Coca-Cola in the Shanghai market (the subagent) makes opportunistic use of a situation in which it does not have to bear the financial consequences of the major residual claimants (the principal and other agents) and has an incentive to enter the nondesignated Coca-Cola market of Hangzhou by crossing the geographic boundary between the two regional monopolies devised by Coca-Cola. The existence of parallel trade in Coca-Cola promotes interregional competition between the Shanghai and Hangzhou bottlers (the agents). This article enhances an understanding of the economic geography of spatial equilibrium, disequilibrium, and quasi-equilibrium of a transnational corporation's distribution system and its artificially created market boundary in China. [source] | |||||||||||||