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Background and aimsMany plant-pollinator interactions are mediated by floral scents that can vary among species, among populations within species and even among individuals within populations. This variation could be innate and unaffected by the environment, but, because many floral volatiles have amino-acid precursors, scent variation also could be affected by differences in nutrient availability among environments. In plants that have coevolved with specific pollinators, natural selection is likely to favour low phenotypic plasticity in floral scent even under different conditions of nutrient availability if particular scents or scent combinations are important for attracting local pollinators.MethodsClonal pairs of multiple seed-families of two Lithophragma bolanderi (Saxifragaceae) populations were subjected to a high and a low nutrient treatment. These plants are pollinated primarily by host-specific Greya moths. It was evaluated how nutrient treatment affected variation in floral scent relative to other vegetative and reproductive traits.Key resultsFloral scent strength (the per-flower emission rate) and composition were unaffected by nutrient treatment, but low-nutrient plants produced fewer and lighter leaves, fewer scapes and fewer flowers than high-nutrient plants. The results held in both populations, which differed greatly in the number and composition of floral scents produced.ConclusionsThe results reveal a strong genetic component both to scent composition and emission level, and partly contrasts with the only previous study that has assessed the susceptibility of floral volatile signals to variation in the abundance of nutrients. These results, and the tight coevolutionary relationship between Lithophragma plants and their specialized Greya moth pollinators, indicate that reproductive traits important to coevolving interactions, such as the floral scent of L. bolanderi, may be locally specialized and more canalized than other traits important for plant fitness.

With firms searching for secured external funding by engaging in multiple bank relationships on the one hand and banks for profit maximization on the other hand, conflicts of interests may arise when firms’ banks demand access to corporate private information. This information can help banks to gauge the creditworthiness of borrowers, but also exposes the latter to losses of secrecy. Thus, firms which are dependant on informative secrecy – especially innovative firms – might incur difficulties when trying to get access to external funding. As rival firms prevail within firms’ own industries, a special focus is on effects of local industry specialization and competition when investigating the quantity of firms’ bank connections. Analysing German firm level and county specific industry data, I find evidence that the number of bank relationships decreases for the cross-section of firms with local industry diversification. The effects of the indicators of industry-specific and overall competition are twofold with the former being positively related to the probability of using multi-bank relationships and the latter negative. Concluding, firms located in industrially specialized areas might rather refrain from relationship lending, due to potential loss of external funding, while innovative firms seem to rely on transaction-based banking. Contrarily, firms located in areas that are diversified w.r.t. industries, firm sizes and corporate landscape engage in relationship banking.

With firms searching for secured external funding by engaging in multiple bank relationships on the one hand and banks for profit maximization on the other hand, conflicts of interests may arise when firms' banks demand access to corporate private information. This information can help banks to gauge the creditworthiness of borrowers, but also exposes the latter to losses of secrecy. Thus, firms which are dependant on informative secrecy -- especially innovative firms -- might incur difficulties when trying to get access to external funding. As rival firms prevail within firms' own industries, a special focus is on effects of local industry specialization and competition when investigating the quantity of firms' bank connections. Analysing German firm level and county specific industry data, I find evidence that the number of bank relationships decreases for the cross-section of firms with local industry diversification. The effects of the indicators of industry-specific and overall competition are twofold with the former being positively related to the probability of using multi-bank relationships and the latter negative. Concluding, firms located in industrially specialized areas might rather refrain from relationship lending, due to potential loss of external funding, while innovative firms seem to rely on transaction-based banking. Contrarily, firms located in areas that are diversified w.r.t. industries, firm sizes and corporate landscape engage in relationship banking. [ABSTRACT FROM AUTHOR]

The majority of herbivorous insects are specialized in host use. Even among insects that use many hosts, local specialization is common with a single host plant often being used in any given locality. Here, we establish such a pattern for the European swallowtail butterfly, Papilio machaon. We sampled larvae on five different natural hosts at eight sites in Sweden, each locality showing local monophagy. We ask what is the underlying reason for this pattern, (1) local genetic adaptation with each population being genetically adapted to the local host, (2) Hopkins' host selection principle with adult females retaining a memory of the larval host and preferring to oviposit on that plant, or (3) the preference/performance hypothesis which posits that females should oviposit on the local plant(s) on which larval fitness is highest. Allozyme analysis supported a relatively low level of population structuring, and oviposition preference tests showed that females from all sites had similar preference rankings of the five host plants. Hence, there was no support for local genetic adaptation or Hopkins'host selection principle. Instead, the results are consistent with the preference/performance hypothesis with local monophagy probably being implemented by a preference ranking of plants in accordance with larval performance. [ABSTRACT FROM AUTHOR]

The article documents the process of defining the prestige hierarchy for a sample of occupations, a required component of a Position generator to estimate social Capital within a local atypical context, from a relational perspective. it describes the results of a mixed-design study conducted to assessing the perceptions of occupational Prestige in Uriangato, a Mexican town highly specialized in producing and selling clothing through small businesses. Through the case study we found a differentiated interpretation of occupational prestige regarding international standards. occupations related to productive specialized local settings, are generally better evaluated. owning a business of manufacturing, trade or services, is a better recognized occupation in comparison with others that, in typical contexts, have greater prestige and socioeconomic status, such as lawyer, teacher or nurse. However, the scale achieved on the basis of the qualitative technique of pile sort, strongly correlates with two internationally standardized scales of occupational Prestige, making it possible to build a locally relevant Position generator to measure social capital, while maintaining comparability to other studies done in different economic or cultural contexts.

The article documents the process of defining the prestige hierarchy for a sample of occupations, a required component of a Position Generator to estimate Social Capital within a local atypical context, from a relational perspective. It describes the results of a mixed-design study conducted to assessing the perceptions of Occupational Prestige in Uriangato, a Mexican town highly specialized in producing and selling clothing through small businesses. Through the case study we found a differentiated interpretation of occupational prestige regarding international standards. Occupations related to productive specialized local settings, are generally better evaluated. Owning a business of manufacturing, trade or services, is a better recognized occupation in comparison with others that, in typical contexts, have greater prestige and socioeconomic status, such as lawyer, teacher or nurse. However, the scale achieved on the basis of the qualitative technique of pile sort, strongly correlates with two Internationally Standardized Scales of Occupational Prestige, making it possible to build a locally relevant Position Generator to measure social capital, while maintaining comparability to other studies done in different economic or cultural contexts. [ABSTRACT FROM AUTHOR]

Abstract: Defining host ranges in parasitoid insects is important both from a theoretical and an applied point of view. Based on the literature, some species seem able to use a wide range of hosts, while field studies indicate possible local host specialization. In koinobiont endoparasitoid species, such specialization could involve physiological processes. We tested the ability of two strains of the cosmopolitan and polyphagous parasitoid Diaeretiella rapae, to develop in three of its recorded aphid host species. Both strains produced high parasitism rates on the cabbage aphid Brevicoryne brassicae and the green peach aphid Myzus persicae but almost no progeny on the cherry-oat aphid Rhopalosiphum padi. This last species was less attacked by female parasitoids. Moreover, parasitoid eggs and larvae were smaller than in the two other host aphid species and their development was delayed. This abnormal development appeared to be due to an incomplete host regulation process, probably related to the low number and the size of teratocytes produced by D. rapae in R. padi individuals. Such a failure as far as gaining control of the host''s metabolism is concerned could play an important role in shaping the host range of parasitoid insects, leading to local variation of the host spectrum in populations from various geographical areas. [Copyright &y& Elsevier]

This article discusses how regional specialization could be explained. Statistics from Nordic countries indicates that industrial concentrations are durable and even reinforced. The phenomenon is rather deductively explained than intensively studied. This article complements the literature on entrepreneurship with the concept 'communities of practice'. Eight municipalities/regions, having more than twice as high rate of employment in mechanical industry as the nation, are subject for comparative studies. The article identifies and explains different types of endogenous processes that complete and multiply the company structure within this industry sector. Conscious localization decisions are exceptions. Regional specialization is rather a product of recirculation of competence based on local practices. Endogenous processes are not reserved to small enterprise regions only, as we could expect from literature. Even if central decisions in large enterprises are significant, entrepreneurial processes take place in most of the large enterprise regions as well. [ABSTRACT FROM AUTHOR]

In recent years, the study of phenotypic and genetic variation has been enhanced by combining genetic, physiological, demographic, and behavioral components of life histories. Using these new approaches, we address the problem of adaptation to environmental heterogeneity by examining in detail the variation of several fitness-related traits in a small passerine bird, the blue tit, which has been extensively studied in habitat mosaics of the Mediterranean region. The response of blue tits to spatial habitat heterogeneity depends on their range of dispersal relative to the size of habitat patches. Dispersal over short distances leads to local specialization, whereas dispersal over long distances leads to phenotypic plasticity. Gene flow between habitats of different quality may produce local maladaptation and a source-sink population structure. However, when habitat-specific divergent selection regimes are strong enough to oppose the effects of gene flow, local adaptation may arise on a scale that is much smaller than the scale of dispersal. [ABSTRACT FROM AUTHOR]

The productivity of forests has been linked to the sensitivity of tree growth to meteorological conditions and their fluctuations, hence moderation of tree sensitivity is one of the goals for climate-smart forest management. For this, tree breeding is among the most effective means, particularly if breeding populations are supplemented with genotypes (provenances) adapted to the expected climates. Nonetheless, heritability of traits is essential for their improvement by breeding. In this study, heritability of growth sensitivity of south-eastern Baltic provenances of Scots pine differing by field performance to meteorological conditions was assessed combining methods of quantitative genetics and dendrochronology. Five parallel provenance trials within the south-eastern Baltic region were investigated. The effects of regional weather drivers of growth (moisture regime in summer, temperature regime in preceding summer and in the dormancy period) were estimated, yet their strengths differed among the provenances, indicating local specialization of metapopulations of Scots pine. The heritability of growth sensitivity to these factors ranged from low to moderate, similarly as observed for the morphometric traits within the region; however, the provenance (genetic) variation appeared to be higher. The differences in heritability of responses, however, indicated uneven adaptive significance of weather conditions. Although the estimates were based on a limited set of genotypes implying caution in the extrapolation of results, the weather-growth relationships and their heritability indicate that sensitivity of growth is a complementary trait aiding breeding of forest reproductive material best suited for future climates. Heritable weather-growth relationships also imply a high potential for forest breeding to moderate the sensitivity of the trees. [ABSTRACT FROM AUTHOR]

In North Carolina, the decorator crab Libinia dubia camouflages almost exclusively with the chemically noxious alga Dictyota menstrualis. By placing this alga on its carapace, the crab behaviorally sequesters the defensive chemicals of the plant and gains protection from omnivorous consumers. However, Dictyota is absent north of North Carolina, whereas Libinia occurs as far north as New England. Crabs from three northern locations where Dictyota is absent (Rhode Island, Connecticut, and New Jersey) camouflaged to match their environment, rather than selectively accumulating any one species. When D. menstrualis was offered to crabs from northern sites, they did not distinguish between it and other seaweeds for camouflage, whereas crabs from Alabama and two locations in North Carolina used D. menstrualis almost exclusively. In addition, in winter and spring, when Dictyota was seasonally absent in North Carolina, Libinia selectively camouflaged with the sun sponge Hymeniacidon heliophila, which was chemically unpalatable to local fishes. Thus, southern crabs were consistent specialists on chemically defended species for camouflage, while northern crabs were more generalized. The geographic shift in crab behavior away from specialization coincides with a reported decrease in both total predation pressure and the frequency of omnivorous consumers. These shifts in the nature and intensity of predation pressure may favor different camouflage strategies (generalist vs. specialist), contributing to the observed geographic differences in camouflage behavior.