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Regional Diversity (regional + diversity)
Selected AbstractsDesign differentiation for global companies: Value exporters and value collectorsDESIGN MANAGEMENT REVIEW, Issue 4 2001Clive Grinyer In the global marketplace, should companies maintain uniform product profiles,some with strong national characteristics,or adapt regionally? Most companies tend toward one end or the other, concludes Clive Grinyer. Clearly distinguishing between "value exporters" and "value collectors," he articulates the advantages and disadvantages of each. Companies must strike their own strategic balance, hopefully without diluting the regional diversity that makes life and consumer choices so interesting. [source] Diversity, distinctiveness and conservation status of the Mediterranean coastal dung beetle assemblage in the Regional Natural Park of the Camargue (France)DIVERSITY AND DISTRIBUTIONS, Issue 6 2001Jorge Miguel Lobo Abstract. The Mediterranean region as a whole has the highest dung beetle species richness within Europe. Natural coastal habitats in this region are among those which have suffered severe human disturbance. We studied dung beetle diversity and distinctiveness within one of the most important coastal protected areas in the west Euro-Mediterranean region (the regional Park of Camargue, southern France) and made comparisons of dung beetle assemblages with other nearby Mediterranean localities, as well as with other coastal protected area (Doñana National Park, Spain). Our finding showed that: (1) The species richness of coastal habitats in the Camargue is low and only grasslands showed a similar level of species richness and abundance to inland habitats of other Mediterranean localities. The unique habitats of the coastal area (beaches, dunes and marshes) are largely colonized by species widely distributed in the hinterland. (2) In spite of their low general distinctiveness, dune and marsh edges are characterized by the occurrence of two rare, vulnerable, specialized and large roller dung beetle species of the genus Scarabaeus. As with other Mediterranean localities, current findings suggest a recent decline of Scarabaeus populations and the general loss of coastal dung beetle communities in Camargue. (3) The comparison of dung beetle assemblages between the Camargue and Doñana shows that, in spite of the low local dung beetle species richness in the Camargue, the regional dung beetle diversity is similar between both protected areas. Unique historical and geographical factors can explain the convergence in regional diversity as well as the striking divergence in the composition of dung beetle assemblages between both territories. [source] Local Diversity, Human Creativity, and Technological InnovationGROWTH AND CHANGE, Issue 3 2001Pierre Desrochers The purpose of this paper is to point out some shortcomings of traditional approaches to the study of "knowledge spillovers" and to suggest an alternative based on how knowledge is actually created and exchanged by individuals. Which regional setting is the best incubator of technological change and economic growth? Is this promoted by regional diversity or specialization of economi activity? This study will include economic analyses of geographically localized "dynamic knowledge externalities, Jacob's externalities, or adding new work to old, industrial classification and technology combination, human creativity, and technology combination through human action and imaginative use of resources. Employees add to, or switch their product line; individuals move from one type of production to another; individuals observe a product/process in another setting and incorporate it; individuals possessing different skills and working for different firms collaborate; and urban diversity and resource collaboration are utilized. It is concluded that problems are solved through the combination of previously unrelated things and that promoting regional specialization at the expense of spontaneously evolved local diversity might be a counter-productive policy. [source] The extent of marketability and consumer preferences for traditional leafy vegetables , a case study at selected markets in GhanaINTERNATIONAL JOURNAL OF CONSUMER STUDIES, Issue 3 2009Wilhemina Quaye Abstract This paper reports on a survey conducted at two major marketing centres in Ghana; Tamale in the dry savannah zone and Kumasi in the forest zone. One hundred traders were interviewed using a semi-structured questionnaire and focus groups discussions held on traders' perceptions and consumer preferences, relative importance and indigenous nutritional knowledge of traditional leafy vegetables (TLVs). The survey established that, with the exception of Xanthosoma mafafa (cocoyam leaves), inter-market distribution of TLVs is limited because of their perishable nature, narrow utilization base and lack of storage techniques. Socio-culturally related factors limiting the distribution of TLVs include regional diversity and ethnic differences in the dietary patterns of the Ghanaian populace, inadequate knowledge about the methods of preparations as well as nutritional and medicinal values of TLVs. The most preferred TLVs as reflected in the consumers' buying behaviour and traders' perceptions are Xanthosoma mafafa (cocoyam leaves), Corchorus spp.(Ayoyo), Amaranthus spp (Alefu) and Hibicus sabdariffa (Bra). The order of preference in the forest zone is Xanthosoma mafafa (cocoyam leaves) > Corchorus spp.(Ayoyo) > Amaranthus spp (Alefu) > Hibicus sabdariffa (Bra), while the reverse order pertains in the savannah zone. [source] Health care insurance in Japan: Beyond a binary vision of State and familyINTERNATIONAL SOCIAL SECURITY REVIEW, Issue 3 2009Kusuto Naïto Abstract Despite significant regional diversity in household structures and the existence of community solidarity in Japan, caring for elderly dependent persons has traditionally been considered an exclusively family, and female, responsibility. However, as a result of socio-demographic changes during the second half of the twentieth century, a public system of health care insurance was introduced in 2000. The objective of this development was to "socialize" family and female care activities. This article presents a critical analysis of Japan's health care insurance system and the context that gave rise to its introduction. An important issue is whether the system meets the needs of the elderly and their carers (family and non-family). A further issue is whether the system can take account of regional diversity, diversity in household situations (above and beyond financial concerns), and societal values and beliefs. The article concludes by arguing that demographic ageing presents a societal requirement for the ongoing adjustment of behaviour patterns and living arrangements. [source] Marine biogeography and ecology: invasions and introductionsJOURNAL OF BIOGEOGRAPHY, Issue 2 2007John C. Briggs Abstract Although biogeography and ecology had previously been considered distinct disciplines, this outlook began to change in the early 1990s. Several people expressed interest in creating a link that would help ecologists become more aware of external influences on communities and help biogeographers realize that distribution patterns had their genesis at the community level. They proposed an interdisciplinary approach called macroecology. This concept has been aided by the advent of phylogeography, for a better knowledge of genetic relationships has had great interdisciplinary value. Two areas of research that should obviously benefit from a macroecological approach are: (1) the question of local vs. regional diversity and (2) the question of whether invader species pose a threat to biodiversity. The two questions are related, because both deal with the vulnerability of ecosystems to penetration by invading species. Biogeographers, who have studied the broad oceanic patterns of dispersal and colonization, tend to regard isolated communities as being open to invasion from areas with greater biodiversity. It became evident that many wide-ranging species were produced in centres of origin, and that the location of communities with respect to such centres had a direct effect on the level of species diversity. Ecologists, in earlier years, thought that a community could become saturated with species and would thereafter be self-sustaining. But recent research has shown that saturation is probably never achieved and that the assembly of communities and their maintenance is more or less dependent on the invasion of species from elsewhere. The study of invasions that take place in coastal areas, usually the result of ship traffic and/or aquaculture imports, has special importance due to numerous opinions expressed by scientists and policy-makers that such invasions are a major threat to biodiversity. However, none of the studies so far conducted has identified the extinction of a single, native marine species due to the influence of an exotic invader. Furthermore, fossil evidence of historical invasions does not indicate that invasive species have caused native extinctions or reductions in biodiversity. [source] Marine nematode deep-sea biodiversity , hyperdiverse or hype?JOURNAL OF BIOGEOGRAPHY, Issue 4 2003P. John D. Lambshead Abstract Nematodes have been identified as a potentially hyperdiverse group and the deep sea as a potentially hyperdiverse environment (i.e. > 1 million species). A large-scale data set from the equatorial central Pacific is used to estimate regional diversity with results that challenge this view; regional diversity is higher in some coastal waters despite lower sample diversity in coastal waters than in the deep sea. The data suggests a paradigm where the deep sea has modest regional diversity, despite high local diversity through patch dynamics, because similar patches in a similar habitat are repeated for considerable distances. Disturbance in shallow water dominates over patch-dynamic mechanisms reducing local diversity but regional diversity is high because of the close packing of multiple habitats within a single region. The Pacific data are also used to demonstrate the pitfalls of extrapolating from local to global diversity. There is no reason to conclude that nematodes are less diverse than other benthic groups, indeed where direct comparison is possible the Nematoda appear to be as diverse as the Polychaeta, the most diverse macrofaunal taxon. This analysis is not consistent with the hypothesis that either marine nematodes or the deep-sea benthos are hyperdiverse raising the question whether any environment or metazoan taxon has more than a million species. [source] Habitat heterogeneity and its influence on benthic biodiversity in oxygen minimum zonesMARINE ECOLOGY, Issue 1 2010Andrew J. Gooday Abstract Oxygen minimum zones (OMZs; midwater regions with O2 concentrations <0.5 ml l,1) are mid-water features that intercept continental margins at bathyal depths (100,1000 m). They are particularly well developed in the Eastern Pacific Ocean, the Arabian Sea and the Bay of Bengal. Based on analyses of data from these regions, we consider (i) how benthic habitat heterogeneity is manifested within OMZs, (ii) which aspects of this heterogeneity exert the greatest influence on alpha and beta diversity within particular OMZs and (iii) how heterogeneity associated with OMZs influences regional (gamma) diversity on continental margins. Sources of sea-floor habitat heterogeneity within OMZs include bottom-water oxygen and sulphide gradients, substratum characteristics, bacterial mats, and variations in the organic matter content of the sediment and pH. On some margins, hard grounds, formed of phosphorites, carbonates or biotic substrata, represent distinct subhabitats colonized by encrusting faunas. Most of the heterogeneity associated with OMZs, however, is created by strong sea-floor oxygen gradients, reinforced by changes in sediment characteristics and organic matter content. For the Pakistan margin, combining these parameters revealed clear environmental and faunal differences between the OMZ core and the upper and lower boundary regions. In all Pacific and Arabian Sea OMZs examined, oxygen appears to be the master driver of alpha and beta diversity in all benthic faunal groups for which data exist, as well as macrofaunal assemblage composition, particularly in the OMZ core. However, other factors, notably organic matter quantity and quality and sediment characteristics, come into play as oxygen concentrations begin to rise. The influence of OMZs on meiofaunal, macrofaunal and megafaunal regional (gamma) diversity is difficult to assess. Hypoxia is associated with a reduction in species richness in all benthic faunal groups, but there is also evidence for endemism in OMZ settings. We conclude that, on balance, OMZs probably enhance regional diversity, particularly in taxa such as Foraminifera, which are more tolerant of hypoxia than others. Over evolutionary timescales, they may promote speciation by creating strong gradients in selective pressures and barriers to gene flow. [source] Patterns of recurrent evolution and geographic parthenogenesis within apomictic polyploid Easter daises (Townsendia hookeri)MOLECULAR ECOLOGY, Issue 11 2006STACEY LEE THOMPSON Abstract Geographic patterns of parthenogenesis and the number of transitions from sexual diploidy to asexual (apomictic) autopolyploidy were examined for 40 populations of the Easter daisy, Townsendia hookeri. Analyses of pollen diameter and stainability characterized 15 sexual diploid and 25 apomictic polyploid populations from throughout the plant's western North American range. Sexual diploids were restricted to two Wisconsin refugia: Colorado/Wyoming, south of the ice sheets, and northern Yukon/Beringia. Chloroplast DNA sequencing uncovered 17 polymorphisms within the ndhF gene and trnK intron, yielding 10 haplotypes. Phylogenetic analyses indicated that five exclusively polyploid haplotypes were derived from four haplotypes that are shared among ploidies, conservatively inferring a minimum of four origins of apomictic polyploidy. Three of these apomictic polyploid origins were derived from southern sexual diploids, while the fourth origin was derived from northern sexual diploids. Analyses of regional diversity were suggestive of a formerly broad distribution for sexual diploids that has become subsequently fragmented, possibly due to the last round of glaciation. As sexual diploids were exclusively found north and south of the glacial maximum, while formerly glaciated areas were exclusively inhabited by asexual polyploids derived from both northern and southern sexual lineages, it is more likely that patterns of glaciation, as opposed to a particular latitudinal trend, played a causal role in the establishment of the observed pattern of geographic parthenogenesis in Easter daisies. [source] A unified mathematical framework for the measurement of richness and evenness within and among multiple communitiesOIKOS, Issue 2 2004Thomas D. Olszewski Biodiversity can be divided into two aspects: richness (the number of species or other taxa in a community or sample) and evenness (a measure of the distribution of relative abundances of different taxa in a community or sample). Sample richness is typically evaluated using rarefaction, which normalizes for sample size. Evenness is typically summarized in a single value. It is shown here that Hurlbert's probability of interspecific encounter (,1), a commonly used sample-size independent measure of evenness, equals the slope of the steepest part of the rising limb of a rarefaction curve. This means that rarefaction curves provide information on both aspects of diversity. In addition, regional diversity (gamma) can be broken down into the diversity within local communities (alpha) and differences in taxonomic composition among local communities (beta). Beta richness is expressed by the difference between the composite rarefaction curve of all samples in a region with the collector's curve for the same samples. The differences of the initial slopes of these two curves reflect the beta evenness thanks to the relationship between rarefaction and ,1. This relationship can be further extended to help interpret species-area curves (SAC's). As previous authors have described, rarefaction provides the null hypothesis of passive sampling for SAC's, which can be interpreted as regional collector's curves. This allows evaluation of richness and evenness at local and regional scales using a single family of well-established, mathematically related techniques. [source] Contexts of Monumentalism: regional diversity at the Neolithic transition in north-west FranceOXFORD JOURNAL OF ARCHAEOLOGY, Issue 1 2002Chris Scarre The origins of funerary monumentalism in north-west France remain inextricably linked to questions surrounding the Neolithic transition in that region. Debate continues over the relative importance of influences from earlier Neolithic communities in north-east or southern France on the Mesolithic communities of western France. An alternative interpretation places these influences within the context of broad processes of change affecting indigenous communities throughout northern and western France during the fifth millennium BC. The evidence from several regions of northern and western France is reviewed in this perspective, with emphasis on the regional character of monument traditions. Though at one level these regional narratives must have been interrelated, the regional diversity of the process must also be underlined. The argument moves us away from simplistic notions of extraneous influences to a more nuanced understanding of change within the context of individual communities at the Mesolithic/Neolithic transition. [source] Regional differences in craniofacial diversity and the population history of Jomon JapanAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 3 2009Tsunehiko Hanihara Abstract The people associated with the Jomon culture, the Neolithic inhabitants of Japan, are one of the key groups in the population history of East Asia, because they retain many archaic characters that may be traced back to Eurasian Upper Palaeolithic hunter,gatherers. In this study, the regional diversity of the Jomon skeletal series was estimated by applying the R-matrix method to 34 craniofacial measurements. The patterns of intraregional variation indicate little effect on the genetic structure of the Jomon from long-term gene flow stemming from an outside source. The regional diversities were further estimated by pooling all individuals into regional aggregates, and by computing the mean variance within local groups in each region. Although the pattern of phenotypic variation differs depending on the unit of analysis, the gradient of the diversity retains its identity. The Hokkaido region, the northernmost part of the Japanese archipelago, has the highest variance, followed by the regions of eastern Japan, while the southwestern regions have the lowest variance. These findings suggest that the Jomon ancestors of the northern part of Japan might have expanded southward to Honshu Island. Global analyses including samples from Eurasia, Africa, and Australia dating roughly to the same chronological periods as those of the Jomon samples, indicate that the Jomon cranial series share part of their ancestral gene pool with early northeastern Asians. The present findings support the archeologically suggested population growth and expansion in the northern half of the Eurasian continent during the late Pleistocene and early Holocene periods. Am J Phys Anthropol, 2009. © 2008 Wiley-Liss, Inc. [source] Innovation and evolution at the edge: origins and fates of gastropods with a labral toothBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 4 2001GÉERAT J. VERMEIJ I combined data from the taxonomy, phytogeny, functional morphology, biogeography, and fossil record of gastropods to probe the origins, distribution, and fates of predatory gastropod clades characterized by the presence of a labral tooth, a downwardly projecting tooth or spine formed at the edge of the outer lip of the shell. A labral tooth occurs in at least 608 species, of which 251 are Recent. Studies of the type and position of the labral tooth, along with other characters, indicate that the labral tooth has evolved independently at least 58 times, beginning in the Campanian epoch of the late Cretaceous. The labral tooth plays a more or less active part in predation on relatively large prey animals that are protected by a hard skeleton. In the Recent fauna, tooth-bearing species are overwhelmingly warm-temperate to tropical in distribution (240 of 251 species; 96%). Within Muricidae (excluding Coralliophilinae), however, there is no discernible latitudinal gradient in the number of tooth-bearing species relative to total regional diversity. First appearances of clades with a labral tooth are overwhelmingly concentrated in the late Oligocene to Pleistocene interval, with the largest number appearing during the early Miocene (12 clades). The temporal pattern differs significantly from that expected on the basis of the number of faunas available per time interval, and is therefore not an artifact of sampling or fossil preservation. The most consistent factor associated with, and permitting the repeated evolution of, the labral tooth is high planktonic primary productivity. Two factors may account for the link between primary productivity and the evolution of labral téeth: (1) the general economic opportunity afforded by ready availability of an access to nutrients, and (2) the greater abundance and sizes range of available suspension-féeding prey animals. Incumbency,the presence of already well-adapted species,often controls evolutionary opportunity. The complementary distributions of major tooth-bearing clades in many parts of the world point to the role of well-adapted incumbents in limiting the adaptive exploration by other clades that could in principle evolve a labral tooth. The elimination of incumbents by extinction, however, does not provide opportunities for other clades to fill the adaptive void. [source] | ||||||||||||||||