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Geographical Proximity (geographical + proximity)
Selected AbstractsCross-Border Exposures and Financial ContagionINTERNATIONAL REVIEW OF FINANCE, Issue 2 2010HANS DEGRYSE ABSTRACT Integrated financial markets provide opportunities for expansion and improved risk sharing, but also pose threats of contagion risk through cross-border exposures. This paper examines cross-border contagion risk over the period 1999,2006. To that purpose we use aggregate cross-border exposures of 17 countries as reported in the Bank for International Settlements Consolidated Banking Statistics. We find that a shock that affects the liabilities of one country may undermine the stability of the entire financial system. Particularly, a shock wiping out 25% (35%) of US (UK) cross-border liabilities against non-US (non-UK) banks could lead to bank contagion eroding at least 94% (45%) of the recipient countries' banking assets. We also find that since 2006 a shock to Eastern Europe, Turkey and Russia affects most countries. Our simulations also reveal that the ,speed of propagation of contagion' has increased in recent years resulting in a higher number of directly exposed banking systems. Finally, we find that contagion is more widespread in geographical proximities. [source] Morphological variation of the five vole species of the genus Microtus (Mammalia, Rodentia, Arvicolinae) occurring in GreeceACTA ZOOLOGICA, Issue 3 2009Stella E. Fraguedakis-Tsolis Abstract Morphometric data for the five vole species of the genus Microtus living in Greece are old, sparse, poor and insufficiently analysed. This work aims to give the first comprehensive morphometric analysis of body and skull inter- and intraspecific variation for M. (M.) guentheri, M. (M.) rossiaemeridionalis, M. (Terricola) subterraneus, M. (T.) felteni and M. (T.) thomasi, applying multivariate statistics to 28 linear morphometric variables. It was based on ample material (202 adult individuals) using samples from localities that adequately cover the entire distributional range of each species in Greece. The five species and the two subgenera (Microtus and Terricola) were morphometrically clearly distinguished and discriminating variables were revealed. However, morphometrics did not provide robust criteria to infer phylogenetic relations among species. Furthermore, three species, M. (M.) guentheri, M. (M.) rossiaemeridionalis and M. (T.) thomasi, exhibited considerable intraspecific size or shape variation, which was mostly random and not associated with geographical proximity. Comparisons with data in the literature, mainly concerning populations of these species from adjacent areas, indicate that the Greek M. (M.) guentheri, M. (M.) rossiaemeridionalis and M. (T.) thomasi tend to be smaller than their conspecifics, while M. (T.) subterraneus and M. (T.) felteni are about equal in size to their Balkan relatives. [source] Fisheries of two tropical lagoons in Ghana, West AfricaFISHERIES MANAGEMENT & ECOLOGY, Issue 6 2004H. R. Dankwa Abstract, The fisheries of two coastal lagoons, Keta and Songor, were studied as part of Ghana Coastal Wetlands Management Project (GCWMP) aimed at sustainable exploitation of wetland resources. Fish samples were obtained with seine nets and cast net as well as from local fishermen. Water quality parameters (pH, dissolved oxygen, temperature and turbidity) were similar in the two lagoons, except for salinity, which was significantly different (P < 0.001). Despite their close geographical proximity, the two lagoons supported different fish assemblages with the blackchin tilapia, Sarotherodon melanotheron Rüppell, and the redchin tilapia, Tilapia guineensis (Bleeker), being the most important commercial fishes in both lagoons. The number of individuals for each species in Songor Lagoon were far more abundant, with densities several orders of magnitude higher than in Keta Lagoon. However, both species were significantly larger (P < 0.01) in the latter [15,121 and 25,157 mm standard length (SL)] than in the former lagoon (30,102 and 15,95 mm SL) for S. melanotheron and T. guineensis respectively. Over-fishing, use of small-size mesh nets, limited mixing of marine and fresh water were some of the factors limiting fish production in both lagoons. [source] Temporal coherence of two alpine lake basins of the Colorado Front Range, U.S.A.FRESHWATER BIOLOGY, Issue 3 2000J. I. L. L. S. Baron 1. Knowledge of synchrony in trends is important to determining regional responses of lakes to disturbances such as atmospheric deposition and climate change. We explored the temporal coherence of physical and chemical characteristics of two series of mostly alpine lakes in nearby basins of the Colorado Rocky Mountains. Using year-to-year variation over a 10-year period, we asked whether lakes more similar in exposure to the atmosphere be-haved more similarly than those with greater influence of catchment or in-lake processes. 2. The Green Lakes Valley and Loch Vale Watershed are steeply incised basins with strong altitudinal gradients. There are glaciers at the heads of each catchment. The eight lakes studied are small, shallow and typically ice-covered for more than half the year. Snowmelt is the dominant hydrological event each year, flushing about 70% of the annual discharge from each lake between April and mid-July. The lakes do not thermally stratify during the period of open water. Data from these lakes included surface water temper-ature, sulphate, nitrate, calcium, silica, bicarbonate alkalinity and conductivity. 3. Coherence was estimated by Pearson's correlation coefficient between lake pairs for each of the different variables. Despite close geographical proximity, there was not a strong direct signal from climatic or atmospheric conditions across all lakes in the study. Individual lake characteristics overwhelmed regional responses. Temporal coherence was higher for lakes within each basin than between basins and was highest for nearest neighbours. 4. Among the Green Lakes, conductivity, alkalinity and temperature were temporally coherent, suggesting that these lakes were sensitive to climate fluctuations. Water tem-perature is indicative of air temperature, and conductivity and alkalinity concentrations are indicative of dilution from the amount of precipitation flushed through by snowmelt. 5. In Loch Vale, calcium, conductivity, nitrate, sulphate and alkalinity were temporally coherent, while silica and temperature were not. This suggests that external influences are attenuated by internal catchment and lake processes in Loch Vale lakes. Calcium and sulphate are primarily weathering products, but sulphate derives both from deposition and from mineral weathering. Different proportions of snowmelt versus groundwater in different years could influence summer lake concentrations. Nitrate is elevated in lake waters from atmospheric deposition, but the internal dynamics of nitrate and silica may be controlled by lake food webs. Temperature is attenuated by inconsistently different climates across altitude and glacial meltwaters. 6. It appears that, while the lakes in the two basins are topographically close, geologically and morphologically similar, and often connected by streams, only some attributes are temporally coherent. Catchment and in-lake processes influenced temporal patterns, especially for temperature, alkalinity and silica. Montane lakes with high altitudinal gradients may be particularly prone to local controls compared to systems where coherence is more obvious. [source] Regional-scale spatial patterns of fire in relation to rainfall gradients in sub-tropical mountains, NW ArgentinaGLOBAL ECOLOGY, Issue 2 2001Héctor Ricardo Grau Abstract 1Spatial patterns of burns are described using Landsat TM images from the sub-tropical mountains of north-west Argentina, over a span of 6 degrees of latitude, and a precipitation range from 250 to 1300 mm/yr. Burns were discriminated easily from unburnt vegetation, mainly by using infrared spectral bands from images taken at the end of the fire season of 1986. 2Nineteen sampling units were defined on the basis of geographical proximity and relatively homogeneous rainfall as inferred from topography, and they were characterized in terms of percentage of burnt area and burn size distribution during one fire season. Regression and Correspondence Analysis were used to assess the relationship between rainfall and spatial descriptors of fire regime. 3Burnt size area was log-normally distributed with most fires in the small-size classes. Of a total of 643 burns, the five largest (more than 2000 hectares each) represented about 30% of the total burnt area. 4Percentage of burnt area, density of burns per unit area, and skewness of the burn-size frequency distribution showed a unimodal pattern along the rainfall gradient, peaking between 700 and 900 mm/yr. Mean and maximum burn size showed a negative but weak correlation with rainfall. The first axis of a Correspondence Analysis ordination of sampling units, on the basis of different descriptors of spatial patterns of fire, was significantly correlated with the rainfall of the sampling unit. 5The results suggest that climate is an important factor controlling fuel conditions and therefore fire regime at the spatial scale of this study, which includes different mountain ranges spanning , 700 km. [source] Islam in Northern Mozambique: A Historical OverviewHISTORY COMPASS (ELECTRONIC), Issue 7 2010Liazzat Bonate This article is a historical overview of two issues: first, that of the dynamics of Islamic religious transformations from pre-Portuguese era up until the 2000s among Muslims of the contemporary Cabo Delgado, Nampula, and to a certain extent, Niassa provinces. The article argues that historical and geographical proximity of these regions to East African coast, the Comoros and northern Madagascar meant that all these regions shared a common Islamic religious tradition. Accordingly, shifts with regard to religious discourses and practices went in parallel. This situation began changing in the last decade of the colonial era and has continued well into the 2000s, when the so-called Wahhabis, Sunni Muslims educated in the Islamic universities of the Arab world brought religious outlook that differed significantly from the historical local and regional conceptions of Islam. The second question addressed in this article is about relationships between northern Mozambican Muslims and the state. The article argues that after initial confrontations with Muslims in the sixteenth century and up until the last decade of the colonial era, the Portuguese rule pursued no concerted effort in interfering in the internal Muslim religious affairs. Besides, although they occupied and destroyed some of the Swahili settlements, in particular in southern and central Mozambique, other Swahili continued to thrive in northern Mozambique and maintained certain independence from the Portuguese up until the twentieth century. Islam there remained under the control of the ruling Shirazi clans with close political, economic, kinship and religious ties to the Swahili world. By establishing kinship and politico-economic ties with the ruling elites of the mainland in the nineteenth century, these families were also instrumental in expanding Islam into the hinterland. Only at the beginning of the twentieth century, the Portuguese rule took full control of the region as a result of military conquests of the ,effective occupation', and imposed new legal and administrative colonial system, called Indigenato, impacting Muslims of northern Mozambique to a great extent. After the independence in 1975, and especially since 1977, the post-independence Frelimo government adopted militant atheism and socialist Marxism, which was short-lived and was abolished in 1983 owing to popular resistance and especially, because of government's perception that its religious policies were fuelling the opposition groups to take arms and join the civil war. The 1980s and 1990s were marked by an acute rivalry and conflicts between the two emerging national umbrella Islamic organizations, the Islamic Council and the Islamic Congress, each representing largely pro-Sufi and anti-Sufi positions. In the 2000s, these organizations became overshadowed by new and more dynamic organizations, such as Ahl Al-Sunna. [source] Contagion Phenomena in Financial Crises: Evidence from the Portuguese and Spanish Exchange Rate Crises in the Early 1990sINTERNATIONAL FINANCE, Issue 2 2003Margarida AbreuArticle first published online: 3 SEP 200 Based on the experience of the Portuguese and Spanish financial crises in the early 1990s, this paper suggests that the spillover of exchange rate crises may reveal a particular dimension of the financial contagion effect: the presumption of mimetic behaviour by monetary authorities. This paper analyses the evolution of the credibility of the Escudo and the Peseta. We set out to test the existence of a contagion effect: that is, in what way does the polarization of exchange rate expectations in a scenario of devaluation of one currency explain the building up of a similar scenario for the other currency? We also examine the transmission mechanisms of such a scenario. Our results suggest the existence of a one-way contagion effect, of the Escudo by the Peseta. Speculative attacks against the Peseta necessarily give rise to speculative attacks against the Escudo, regardless of the evolution of the ,fundamentals' of the Escudo. In this case, the spillover of financial crises could be better understood by the anticipated mimetic behaviour of monetary authorities, rather than by the geographical proximity of the countries in question or by the identical performance of the economies of both. [source] Proximity and inter-organizational collaboration: A literature reviewINTERNATIONAL JOURNAL OF MANAGEMENT REVIEWS, Issue 2 2006J. Knoben The proximity concept is used in many different ways in the literature. These dimensions of proximity are, however, defined and measured in many different (sometimes even contradictory) ways, show large amounts of overlap, and often are under- or over-specified. The goal of this paper is to specify the different dimensions of proximity relevant in inter-organizational collaboration more precisely and to provide definitions of these dimensions. The research presented contributes to reducing the ambiguity of the proximity concept as used in the literature. Based on the above, the following research question is addressed in this paper: ,Which dimensions of proximity are relevant in inter-organizational collaboration and how are they defined?' A systematic literature review is presented in order to disentangle the dimensions of the proximity concept. Based on this literature review, three dimensions of proximity relevant in inter-organizational collaboration are distinguished: geographical proximity, organizational proximity and technological proximity. Examples (case studies) from the literature are used to illustrate the current conceptual ambiguity as well as to clarify how the proposed dimensions of proximity reduce this conceptual ambiguity. [source] Fish assemblages of the Casiquiare River, a corridor and zoogeographical filter for dispersal between the Orinoco and Amazon basinsJOURNAL OF BIOGEOGRAPHY, Issue 9 2008Kirk O. Winemiller Abstract Aim, The aim of this study was to determine whether the Casiquiare River functions as a free dispersal corridor or as a partial barrier (i.e. filter) for the interchange of fish species of the Orinoco and Negro/Amazon basins using species assemblage patterns according to geographical location and environmental features. Location, The Casiquiare, Upper Orinoco and Upper Negro rivers in southern Venezuela, South America. Methods, Our study was based on an analysis of species presence/absence data and environmental information (11 habitat characteristics) collected by the authors and colleagues between the years 1984 and 1999. The data set consisted of 269 sampled sites and 452 fish species (> 50,000 specimens). A wide range of habitat types was included in the samples, and the collection sites were located at various points along the entire length of the Casiquiare main channel, at multiple sites on its tributary streams, as well as at various nearby sites outside the Casiquiare drainage, within the Upper Orinoco and Upper Rio Negro river systems. Most specimens and field data used in this analysis are archived in the Museo de Ciencias Naturales in Guanare, Venezuela. We performed canonical correspondence analysis (CCA) based on species presence/absence using two versions of the data set: one that eliminated sites having < 5 species and species occurring at < 5 sites; and another that eliminated sites having < 10 species and species occurring at < 10 sites. Cluster analysis was performed on sites based on species assemblage similarity, and a separate analysis was performed on species based on CCA loadings. Results, The CCA results for the two versions of the data set were qualitatively the same. The dominant environmental axis contrasted assemblages and sites associated with blackwater vs. clearwater conditions. Longitudinal position on the Casiquiare River was correlated (r2 = 0.33) with CCA axis-1 scores, reflecting clearwater conditions nearer to its origin (bifurcation of the Orinoco) and blackwater conditions nearer to its mouth (junction with the Rio Negro). The second CCA axis was most strongly associated with habitat size and structural complexity. Species associations derived from the unweighted pair-group average clustering method and pair-wise squared Euclidean distances calculated from species loadings on CCA axes 1 and 2 showed seven ecological groupings. Cluster analysis of species assemblages according to watershed revealed a stronger influence of local environmental conditions than of geographical proximity. Main conclusions, Fish assemblage composition is more consistently associated with local environmental conditions than with geographical position within the river drainages. Nonetheless, the results support the hypothesis that the mainstem Casiquiare represents a hydrochemical gradient between clearwaters at its origin and blackwaters at its mouth, and as such appears to function as a semi-permeable barrier (environmental filter) to dispersal and faunal exchanges between the partially vicariant fish faunas of the Upper Orinoco and Upper Negro rivers. [source] Arctiid moth ensembles along a successional gradient in the Ecuadorian montane rain forest zone: how different are subfamilies and tribes?JOURNAL OF BIOGEOGRAPHY, Issue 1 2006Nadine Hilt Abstract Aim, We examined changes in the species diversity and faunal composition of arctiid moths along a successional gradient at a fine spatial scale in one of the world's hot spots for moths, the Andean montane rain forest zone. We specifically aimed to discover whether moth groups with divergent life histories respond differentially to forest recovery. Location, Southern Ecuador (province Zamora-Chinchipe) along a gradient from early successional stages to mature forest understorey at elevations of 1800,2005 m a.s.l. Methods, Moths were sampled with weak light traps at 21 sites representing three habitat categories (early and late succession, mature forest understorey), and were analysed at species level. Relative proportions were calculated from species numbers as well as from specimen numbers. Fisher's , was used as a measure of local diversity, and for ordination analyses non-metric multidimensional scaling (NMDS) was carried out. Results, Proportions of higher arctiid taxa changed distinctly along the successional gradient. Ctenuchini (wasp moths) contributed more strongly to ensembles in natural forest, whereas Lithosiinae (lichen moths) decreased numerically with forest recovery. Arctiid species diversity (measured as Fisher's ,) was high in all habitats sampled. The three larger subordinated taxa contributed differentially to richness: Phaegopterini (tiger moths) were always the most diverse clade, followed by Ctenuchini and Lithosiinae. Local species diversity was higher in successional habitats than in forest understorey, and this was most pronounced for the Phaegopterini. Dominance of a few common species was higher, and the proportion of species represented as singletons was lower, than reported for many other tropical arthropod communities. NMDS revealed a significant segregation between ensembles from successional sites and from forest understorey for all larger subordinated taxa (Phaegopterini, Ctenuchini, Lithosiinae). Abandoned pastures held an impoverished, distinct fauna. Faunal segregation was more pronounced for rare species. Ordination axes reflected primarily the degree of habitat disturbance (openness of vegetation, distance of sites from mature forest) and, to a lesser extent, altitude, but not distance between sampling sites. Main conclusions, Despite the geographical proximity of the 21 sites and the pronounced dispersal abilities of adult arctiid moths, local ecological processes were strong enough to allow differentiation between ensembles from mature forest and disturbed sites, even at the level of subfamilies and tribes. Differences in morphology and life-history characteristics of higher arctiid taxa were reflected in their differential representation (proportions of species and individuals) at the sites, whereas patterns of alpha and beta diversity were concordant. However, concordance was too low to allow for reliable extrapolation, in terms of biodiversity indication, from one tribe or subfamily to the entire family Arctiidae. Phaegopterini (comprising more putative generalist feeders during the larval stages) benefited from habitat disturbance, whereas Ctenuchini (with host-specialist larvae) were more strongly affiliated with forest habitats. [source] Entrepreneurial Access and Absorption of Knowledge Spillovers: Strategic Board and Managerial Composition for Competitive AdvantageJOURNAL OF SMALL BUSINESS MANAGEMENT, Issue 2 2006David B. Audretsch The resource theory of the firm implies that knowledge is a key resource bestowing a competitive advantage for entrepreneurial firms. However, it remains rather unclear up to now how new ventures and small businesses can access knowledge resources. The purpose of this study was to suggest two strategies, in particular, that facilitate entrepreneurial access to and absorption of external knowledge spillovers: the attraction of managers and directors with an academic background. Based on data on board composition of 295 high-technology firms, the results clearly demonstrate the strong link between geographical proximity to research-intense universities and board composition. [source] The genetic structure of cattle populations (Bos taurus) in northern Eurasia and the neighbouring Near Eastern regions: implications for breeding strategies and conservationMOLECULAR ECOLOGY, Issue 18 2007MENG-HUA LI Abstract We investigated the genetic structure and variation of 21 populations of cattle (Bos taurus) in northern Eurasia and the neighbouring Near Eastern regions of the Balkan, the Caucasus and Ukraine employing 30 microsatellite markers. By analyses of population relationships, as well as by a Bayesian-based clustering approach, we identified a genetic distinctness between populations of modern commercial origin and those of native origin. Our data suggested that northern European Russia represents the most heavily colonized area by modern commercial cattle. Further genetic mixture analyses based on individual assignment tests found that native Red Steppe cattle were also employed in the historical breeding practices in Eastern Europe, most probably for incorporating their strong and extensive adaptability. In analysis of molecular variance, within-population differences accounted for ~90% of the genetic variation. Despite some correspondence between geographical proximity and genetic similarity, genetic differentiation was observed to be significantly associated with the difference in breeding purpose among the European populations (percentage of variance among groups and significance: 2.99%, P = 0.02). Our findings give unique genetic insight into the historical patterns of cattle breeding practices in the former Soviet Union. The results identify the neighbouring Near Eastern regions such as the Balkan, the Caucasus and Ukraine, and the isolated Far Eastern Siberia as areas of ,genetic endemism', where cattle populations should be given conservation priority. The results will also be of importance for cost-effective management of their future utilization. [source] Nuclear Deterrence and Animosity in Japan-North Korean Relations: Steps to CoexistencePACIFIC FOCUS, Issue 1 2006Anthony DiFilippo The relationship between Japan and North Korea continues to be characterized by a considerable amount of animus and distrust, their geographical proximity notwithstanding. While the "history problem" still creates antagonism in the bilateral relationship, several other matters, such as the North Korean nuclear crisis and the missile and abduction issues, have not made the prospects for rapprochement especially good. Also not helping to better this very strained bilateral relationship is Japan's recent willingness to strengthen its security alliance with the United States and Washington's policy toward North Korea, which Pyongyang sees as uncompromising and hubristic. Of particular concern is that both Japan and North Korea reason that a real or claimed nuclear deterrent force is necessary for the purpose of national security. This article argues that Tokyo and Pyongyang need to implement bold measures that palpably demonstrate their commitment to improving bilateral ties, stressing that trust-building actions are important for them to experience peaceful coexistence. [source] Spatial patterns of inventors' mobility: Evidence on US urban areasPAPERS IN REGIONAL SCIENCE, Issue 2 2010Stefano Breschi Inventor; mobility; knowledge spillovers; geographical proximity Abstract This paper aims at contributing to the research on knowledge spillovers and their spatial extent by presenting new empirical evidence on a key mechanism driving and directing knowledge diffusion processes, namely, the mobility of knowledge and highly-skilled workers. The analysis is based on a rich data set on US inventors and their patents filed at the European Patent Office from 1978 to 2004. Findings indicate that two distinctive spatial patterns can be detected: inventors move both at short and large spatial distances (i.e., three hours and more than 8 hours driving distance, respectively) in similar proportions. Interestingly, in the largest innovative urban areas inventors' inflows and outflows primarily involve distant rather than neighbour areas. Resumen El objetivo de este artículo es contribuir a la investigación sobre spillovers de conocimiento y su amplitud espacial ya que presenta nuevas pruebas empíricas sobre un mecanismo clave para impulsar y dirigir los procesos de difusión de conocimiento, concretamente la movilidad de conocimiento y de mano de obra altamente especializada. El análisis está basado en un conjunto de datos exhaustivo sobre inventores estadounidenses y las patentes inscritas por ellos en la Oficina Europea de Patentes desde 1978 a 2004. Los resultados indican que se pueden detectar dos patrones espaciales distintivos: los inventores se mueven tanto a distancias cortas como largas (concretamente tres horas y más de ocho horas en automóvil, respectivamente) en proporciones similares. Es interesante mencionar que, en las áreas urbanas innovadoras más grandes, los flujos de entrada y salida de inventores están asociados principalmente a áreas lejanas en vez de a áreas vecinas. [source] Determining the species status of one of the world's rarest frogs: a conservation dilemmaANIMAL CONSERVATION, Issue 1 2001Andrew Holyoake New Zealand's native frogs (genus Leiopelma) are considered to be archaic amphibians of exceptional scientific interest that appear to have remained virtually unchanged for 160-200 million years. They are among the rarest extant amphibians and are highly restricted in distribution, confined to isolated, highly disjunct, populations on the North Island and a few small offshore islands in Cook Strait. Previous investigations have suggested, based on patterns of allozyme variation, that the Stephens Island frog (Leiopelma hamiltoni) and Archey's frog (L. archeyi) are sister taxa to the exclusion of the Maud Island frog, a species in close geographical proximity to the Stephens Island frog and previously viewed as a population of this species. As a consequence of these data, a new species, L. pakeka, the Maud Island Frog, has been described. This new species definition has dramatically enhanced the conservation status of L. hamiltoni, of which there are probably fewer than 150 individuals. In this study we re-examine the systematics of the Leiopelmatidae using mtDNA sequence analyses. Partial 12 S ribosomal RNA and cytochrome b (Cyt b) gene sequences were obtained for 57 frogs from six populations representing all four extant Leiopelma species. Contrary to previous reports we find L. pakeka and L. hamiltoni to be monophyletic. The amount of variation evident between these present species (<1% for Cyt b) is comparable to that seen between populations of L. archeyi. Based on these data, classification of L. pakeka and L. hamiltoni as separate species appears to be unwarranted, but they may be sufficiently distinct to warrant classification as evolutionarily significant units. [source] Genetic structure of Eurasian cattle (Bos taurus) based on microsatellites: clarification for their breed classification,ANIMAL GENETICS, Issue 2 2010M.-H. Li Summary We pool three previously published data sets and present population genetic analyses of microsatellite variation in 48 Bos taurus cattle breeds from a wide range of geographical origins in Eurasia, mostly its northern territory. Bayesian model-based clustering reveals six distinct clusters: besides a single-population cluster of the Yakutian Cattle from Far Eastern Siberia and a cluster of breeds characteristic of an early origin, the other four major clusters largely correspond to previously defined morphological subgroups of Red Lowland, Lowland Black-Pied, Longhorned Dairy and North European Polled cattle breeds. The results highlighted past expansion events of the productive breeds such as Danish Red, Angeln, Holstein-Friesian and Ayrshire in northern and Eastern Europe. Based on genetic assignment of the breeds and the availability of breed information, we provide a preliminary classification of the five breeds that were to date undefined. Furthermore, in the analysis of molecular variance, despite some correspondence between geographical proximity and genetic similarity, the breed classification appears to be a better predictor of genetic structure in the cattle populations (the among-group variance component: breed classification, 2.47%, P < 0.001; geographical division, 0.77%, P < 0.001). [source] Genetic patterns and pollination in Ophrys iricolor and O. mesaritica (Orchidaceae): sympatric evolution by pollinator shiftBOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 4 2009PHILIPP M. SCHLÜTER Ophrys iricolor and O. mesaritica are a pair of morphologically similar, closely related sexually deceptive orchids from the eastern Mediterranean. Ophrys iricolor is known to be pollinated by Andrena morio males and the specific pollinator of Ophrys mesaritica is determined as Andrena nigroaenea. Amplified fragment length polymorphism revealed O. iricolor and O. mesaritica to be genetically intermixed on the whole, although populations of O. iricolor and O. mesaritica in geographical proximity are strongly differentiated, suggesting that specific pollinators locally differentiate these taxa. Based on the available biological data and the system of pollinator attraction operative in Ophrys, we hypothesize that O. mesaritica may have arisen from O. iricolor by pollinator shift and that this is more probable than scenarios invoking hybridization as a result of mispollination by rare, non-specific flower visitors or specifically attracted insects. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159, 583,598. [source] | ||||||||||||||||