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Intense Competition (intense + competition)
Selected AbstractsAdaptive radiation through phenological shift: the importance of the temporal niche in species diversificationECOLOGICAL ENTOMOLOGY, Issue 1 2009JEAN-MARIE SACHET Abstract 1.,Phenological shift in oviposition in seed predators may be a key factor for adaptive radiation if temporal differences lead to less intense competition. 2.,This hypothesis was tested at two sites in the French Alps in three sympatric species of larch cone flies grouped into two phenological groups (early and late) differing in adult emergence and oviposition timing by approximately 2 weeks. The present study assessed the intensity of competition within and between groups by measuring four larval traits. Cone traits were measured, and the impact of early species parasitism on cone development was assessed. 3.,The occupation of the central axis of a developing cone by one early larva has a strong detrimental effect on cone growth and seed production. However, there was almost no correlation between the variables measured on the cones and on the larvae, suggesting that the resources available were not limiting. 4.,Inter-group competition had no significant effect on early larvae. In contrast, both inter- and intra-group competition had a significant negative effect on late larvae length (,11% and ,16% respectively), dry mass (,8% and ,23%), and lipid mass (,15% and ,26%). The intensity of competition was stronger among larvae in the same phenological group, which is consistent with the hypothesis that shifts in oviposition promote adaptive radiation in larch cone flies by reducing competition among larvae. [source] Benefits of communal breeding in burying beetles: a field experimentECOLOGICAL ENTOMOLOGY, Issue 3 2000Anne-Katrin Eggert Summary 1. The ultimate causes of communal breeding and joint parental care in various species of Nicrophorus burying beetles have not been resolved satisfactorily. One hypothesis suggests that females remain on the carcass for extended periods of time because joint defence affords them improved probabilities of retaining the carcass successfully in the face of intense competition from intra-generic competitors. 2. In a field experiment designed to test this hypothesis in N. defodiens (Mannerheim), breeding associations of two females and a male were no more successful at retaining their carcass than were monogamous pairs, lending no support to the hypothesis. 3. Intra-generic intruders that usurped already-buried carcasses were typically much larger than the original residents. 4. The body size of original residents affected both the burial depth and the probability of a takeover. Larger beetles buried the carcass deeper and were more likely to retain possession of the carcass. Group composition also did not affect the depth at which carcasses were buried. 5. Severe and even fatal injuries incurred by some residents indicated the occurrence of violent and damaging fights between competitors over carcasses in the field. [source] ISTANBUL'S BOSTANS: A MILLENNIUM OF MARKET GARDENS,GEOGRAPHICAL REVIEW, Issue 3 2004PAUL J. KALDJIAN ABSTRACT. For centuries, a network of market gardens throughout Istanbul provisioned the city with fresh vegetables. These bostans and their gardeners held a respected place in Istanbul life, contributing to the city's food and employment needs. Today, only fragments remain. Massive urban development, intense competition for metropolitan space, modernization, changing institutions and laws, and the global industrialization of food have threatened this tradition with extinction. But in spite of the overwhelming forces behind their demise, some of Istanbul's bostans persist. Efforts to support and promote the gardens, and to draw from the expertise and experience of their gardeners, are emerging. From a historical perspective, this article examines Istanbul's bostans to understand their meaning and contribution to the city's people and landscape. [source] Property Rights Protection of Biotechnology InnovationsJOURNAL OF ECONOMICS & MANAGEMENT STRATEGY, Issue 4 2005Diana M. Burton Protection of intellectual property embedded in self-replicating biological innovations, such as genetically modified seed, presents two problems for the innovator: the need for copy protection of intellectual property and price competition between new seed and reproduced seed. We consider three regimes in two periods with asymmetric information: short-term contracts, biotechnological protection, and long-term contracts. We find that piracy imposes more intense competition for seed sales than does durability alone. Technology protection systems yield highest firm profit and long-term contracts outperform short-term contracts. Farmers prefer, in order, long-term, short-term, and biotechnical protection. Depending on monitoring cost, long-term contracts may be socially preferred to short-term contracts, with both preferred to biotechnical protection. [source] Parental investment, sexual selection and sex ratiosJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 4 2008HANNA KOKKO Abstract Conventional sex roles imply caring females and competitive males. The evolution of sex role divergence is widely attributed to anisogamy initiating a self-reinforcing process. The initial asymmetry in pre-mating parental investment (eggs vs. sperm) is assumed to promote even greater divergence in post-mating parental investment (parental care). But do we really understand the process? Trivers [Sexual Selection and the Descent of Man 1871,1971 (1972), Aldine Press, Chicago] introduced two arguments with a female and male perspective on whether to care for offspring that try to link pre-mating and post-mating investment. Here we review their merits and subsequent theoretical developments. The first argument is that females are more committed than males to providing care because they stand to lose a greater initial investment. This, however, commits the ,Concorde Fallacy' as optimal decisions should depend on future pay-offs not past costs. Although the argument can be rephrased in terms of residual reproductive value when past investment affects future pay-offs, it remains weak. The factors likely to change future pay-offs seem to work against females providing more care than males. The second argument takes the reasonable premise that anisogamy produces a male-biased operational sex ratio (OSR) leading to males competing for mates. Male care is then predicted to be less likely to evolve as it consumes resources that could otherwise be used to increase competitiveness. However, given each offspring has precisely two genetic parents (the Fisher condition), a biased OSR generates frequency-dependent selection, analogous to Fisherian sex ratio selection, that favours increased parental investment by whichever sex faces more intense competition. Sex role divergence is therefore still an evolutionary conundrum. Here we review some possible solutions. Factors that promote conventional sex roles are sexual selection on males (but non-random variance in male mating success must be high to override the Fisher condition), loss of paternity because of female multiple mating or group spawning and patterns of mortality that generate female-biased adult sex ratios (ASR). We present an integrative model that shows how these factors interact to generate sex roles. We emphasize the need to distinguish between the ASR and the operational sex ratio (OSR). If mortality is higher when caring than competing this diminishes the likelihood of sex role divergence because this strongly limits the mating success of the earlier deserting sex. We illustrate this in a model where a change in relative mortality rates while caring and competing generates a shift from a mammalian type breeding system (female-only care, male-biased OSR and female-biased ASR) to an avian type system (biparental care and a male-biased OSR and ASR). [source] Seasonality of Competition in Early Development of Subtidal Encrusting CommunitiesMARINE ECOLOGY, Issue 3-4 2000Ben C. Maughan Abstract. Settlement panels immersed at Lough Hyne, County Cork, Ireland, at six stations with widely different flow regimes were retrieved at monthly intervals. Between 40 and 62 taxa were identified at each station during the study period. Percentage cover, number of interactions and number of recruits were recorded. Space occupied was found to vary more than 2.5 orders of magnitude between stations and seasons (0.3 , 82 %). Competition for space was most intense during summer, when recruitment was highest. More than 3600 interactions between pairs of species were recorded and competitive matrices are presented for the two stations with the most interactions. Both number of interactions and % cover were significantly higher at sites with greater water flow. The nature and the degree of competition varied between sites, with the most intense competition occurring in the very high flow sites with a large proportion of intraspecific encounters. Colonial species were more evident at the sites with high flow. Certain solitary species (notably Anomia ephippium and Pomatoceros spp.) were successful competitors in encounters with cheilostomatid bryozoans. Solitary species may prevent space monopolisation by the faster-growing bryozoans. ,Typical' early successional species, notably bryozoans such as Celleporella hyalina and Microporella ciliata, were more abundant at the more disturbed sites, implying either a larger adult population and/or preferential settlement of these species at such sites. [source] T-AKE: Acquiring the Environmentally Sound Ship of the 21st CenturyNAVAL ENGINEERS JOURNAL, Issue 3 2006Cdr. Stephen P. Markle USN (Ret.) P.E. Department of Defense (DoD) program managers are increasingly challenged with the difficulties of balancing the risks associated with cost, schedule, and performance in an era of intense competition for increasingly scarce resources. Requirements associated with environmental, safety, and health (ESH), in the context of thirty to forty-year service lives, have not been consistently, or in some cases adequately, addressed in DoD programs. Environmental protection (EP) requirements generally do not fit the normal requirements generation and product synthesis model typically applied to weapon system development. As with all requirements, early identification is the key to integration into the total system. Recognition that EP requirements must be integrated at program conception led to development of the ESH Integration Model by the U.S. Navy Lewis and Clark (T-AKE) Auxiliary Cargo Ammunition Ship Program. Institutionalization of this model has enabled the T-AKE Program to establish EP performance requirements for the twelve-ship class that substantially reduce the environmental footprint of the Navy. Compared to the fifteen ships that it will be replacing, T-AKE will require fifty percent less manning and reduce waste streams by seventy percent enabling an annual life cycle cost savings of $5M in ashore waste disposal costs. The T-AKE Program has been the first to achieve the Chief of Naval Operations vision for the "Environmentally Sound Warship of the 21st Century" through design integration of EP requirements. [source] Conundrums of competitive ability in plants: what to measure?OIKOS, Issue 3 2002LonnieW. A survey of recent literature indicates that competitive ability in plants has been measured, in most studies, only in terms of the relative intensity of size suppression experienced by competitors within one growing season. Far fewer studies have recorded relative success in terms of survival and even fewer studies have recorded fecundity under competition. Differences in size suppression are usually assumed to reflect differences in relative abilities to deny resources to competitors. However, most previous studies have failed to control or account for other sources of variation in the size suppression that plants experience under competition, i.e. variation between mixtures in the resource supply/demand ratio (approach to carrying capacity), or variation in the degree of niche overlap between competitors, or variation in the intensity of concurrent facilitative interactions between competitors. For future studies, much greater caution is required in recognizing these inherent limitations of traditional measures of competitive ability and, hence, guarding against unfounded conclusions or predictions about potential for competitive success that are based on these measures. There is also a significant challenge for future studies to adopt empirical approaches for minimizing these limitations. Some initial recommendations are considered here based on an emerging view of competitive ability measured in terms of traits associated with all three conventional components of Darwinian fitness, i.e. not just growth (plant size) but also survival and fecundity allocation (offspring production per unit plant size per unit time). According to this model, differences in competitive ability imply differences in the ability, despite intense competition (i.e. low resource supply/demand ratio), to recruit offspring into the next generation and thereby limit offspring recruitment by other plants. The important traits of competitive ability, therefore, are not only those that allow a plant to deny resources to competitors, suppress their sizes and hence, maximize the plant's own size, but also those traits that allow the plant to withstand suppression from competition enough to persist, both as an individual (through survival) and across generations (through descendants). [source] Triangular Contests and Caucus Rhetoric at the 1885 General Election*PARLIAMENTARY HISTORY, Issue 2 2008JAMES OWEN This article explores the role played by late-Victorian political associations during parliamentary election campaigns. The central hypothesis is that party organisation, known popularly as the ,caucus', is best understood as a rhetorical device used by politicians and the press to gain legitimacy in the new context created by an expanded and quasi-democratic electorate. The hypothesis is tested by examining the 1885 general election campaigns in Nottingham West and Sheffield Central. Both constituencies witnessed a triangular contest whereby an ,additional' candidate, standing on a radical platform, entered the campaign and pursued a distinctly ,anti-caucus' agenda that was aimed primarily at the local Liberal Party Association. The manner in which the ,caucus' issue was articulated by all sides involved throws new light on the role played by party organisation during this period. While all sides described their association in a way that both defended and asserted its legitimacy, they equally used ,anti-caucus' rhetoric to diminish the credibility of their opponent's organisation, even though they were emulating the deeds they were denouncing. Indeed, it was those within official Liberalism that indulged in the most virulent ,anti-caucus' rhetoric. Thus, it is suggested that, with regard to the attitude of radicals towards official Liberalism, this ,anti-caucus' rhetoric reflected not a real popular resistance against party organisation or ,party', but simply intense competition and imitation between rival ,caucuses'. [source] Using emotional benefits as a differentiation strategy in saturated marketsPSYCHOLOGY & MARKETING, Issue 11 2009Ramo Barrena The high level of product substitution in most consumer markets often makes it difficult to match supply with demand, especially in sectors with mature, saturated markets with intense competition and a high degree of product differentiation. The difficulty of using technical characteristics such as quality and/or price to differentiate products suggests that marketers could profit from gaining more insight into the way in which consumers' purchase decisions are influenced by their perceived emotions. This paper investigates this issue in the wine market, a highly saturated market with homogeneous supply, obtaining results that appear to support the notion that emotions do indeed play a part in consumer choice structures, which show a higher degree of abstraction in those segments that report a greater number of perceived emotions. This considerably complicates the task of creating a differentiated marketing strategy, in the sense that suppliers need to give much greater consideration to consumers' self-awareness. © 2009 Wiley Periodicals, Inc. [source] Buyers' Miscoordination, Entry and Downstream Competition,THE ECONOMIC JOURNAL, Issue 531 2008Chiara Fumagalli This article shows that buyers' coordination failures might prevent entry in an industry with an incumbent firm and a more efficient potential entrant. If there were a single buyer, or if all buyers formed a central purchasing agency, coordination failures would be avoided and efficient entry would always occur. More generally, exclusion is less likely the lower the number of buyers. For any given number of buyers, exclusion is less likely the more fiercely buyers compete in the downstream market. First, intense competition may prevent miscoordination equilibria from arising; second, in cases where miscoordination equilibria still exist, it lowers the maximum price that the incumbent can sustain at such exclusionary equilibria. [source] Organizing for Radical Innovation: An Exploratory Study of the Structural Aspects of RI Management Systems in Large Established FirmsTHE JOURNAL OF PRODUCT INNOVATION MANAGEMENT, Issue 6 2006Gina Colarelli O'Connor To escape the intense competition of today's global economy, large established organizations seek growth options beyond conventional new product development that leads to incremental changes in current product lines. Radical innovation (RI) is one such pathway, which results in organically driven growth through the creation of whole new lines of business that bring new to the world performance features to the market and may result in the creation of entirely new markets. Yet success is elusive, as many have experienced and scholars have documented. This article reports results of a three-year, longitudinal study of 12 large established firms that have declared a strategic intent to evolve their RI capabilities. In contrast to other academic research that has analyzed specific projects to understand management practices appropriate for RI, the present research reported explores the evolution of management systems for enabling radical innovation to occur repeatedly in large firms and reports on one aspect of this management system: organizational structures for enabling and nurturing RI. To consider organizational structure as a venue for capability development is new in the management of innovation and dynamic capabilities literatures. Conventional wisdom holds that RIs should be incubated outside the company and assimilated once they have gained traction in the marketplace. Numerous experiments with organizational structures were observed that instead work to manage the interfaces between the RI management system and the mother organization. These structures are described here, and insights are drawn out regarding radical innovation competency requirements, transition challenges, senior leadership mandates, and business-unit ambidexterity. The centerpiece of this research is the explication of the Discovery,Incubation,Acceleration framework, which details three sets of necessary, though not sufficient competencies, for building an RI capability. [source] | ||||||||||||||||