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1.
Biogeographers, ecologists, palaeontologists, and conservation managers often deal with checklists in which not all individuals have been identified to a species level, or the accuracy of species identification is questionable. Is it possible and credible to investigate species richness based on such checklists? Studies on macrofauna in the Far Eastern seas, eastern Arctic seas, and adjacent waters of the Pacific and Arctic Oceans suggest that in different habitats and for diverse taxa, species, and higher taxa richness strongly correlate with each other and increase with an expansion in the study area and sample size according to the species–area law. Such an increase is higher in the bottom zone than in the pelagic. Species and higher taxa richness also show a decrease from lower to higher latitudes, which is in line with the Humboldt–Wallace’s law. According to Willis’ law and self-similarity in the organisation of taxonomic levels, species richness can be assessed based on the genus, family, and order richness. In other words, supraspecies richness itself can tell us the same as species richness and therefore certain global patterns revealed at the species level may also be revealed at the supraspecies level. Such a concordance in general trends among richness parameters at different taxonomic levels in practice implies that species richness can be studied based on lists that lack species identifications or lists with doubtful species identification. We suggest bolder use of supraspecies richness in science and practice, discussing the disadvantages and advantages of this approach.  相似文献   
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Abstract. This paper examines the initial location choice of legal employment‐based immigrants to the United States using Immigration and Naturalization Service data on individual immigrants, as well as economic, demographic, and social data to characterize the 298 metropolitan areas we define as the universal choice set. Focusing on interactions between place characteristics and immigrant characteristics, we provide multinomial logit model estimates for the location choices of about 38,000 employment‐based immigrants to the United States in 1995, focusing on the top 10 source countries. We find that, as groups, immigrants from nearly all countries are attracted to large cities with superior climates, and to cities with relatively well‐educated adults and high wages. We also find evidence that employment‐based immigrants tend to choose cities where there are relatively few immigrants of nationalities other than their own. However, when we introduce interaction terms to account for the sociodemographic characteristics of the individual immigrants, we find that the estimated effects of location destination factors can reverse as one takes account of the age, gender, marital status, and previous occupation of the immigrants.  相似文献   
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This article deals with the early colonization of the Russian Barents Sea Coast (the so-called Murman Coast) in the middle of the 19th and early 20th century. It focuses mainly on the household economy and economic adaptation in the area by groups of Finnish, Russian, Karelian, Norwegian and Sami colonists. The opening up of the new territory by the colonists resulted partly in the employment of traditional methods of using natural resources and partly in the culture of these groups being transformed. Based on this, two different patterns of using natural resources were singled out within the ethnic groups that settled on the Murman Coast (western and eastern). These patterns were more suited to the new living conditions in each of the respective areas, and became the basis for different trends in the economic development of the Murman Coast.  相似文献   
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Cao, Y., Shih, C., Bashkuev, A. & Ren, D., September 2015. Revision and two new species of Itaphlebia (Nannochoristidae: Mecoptera) from the Middle Jurassic of Inner Mongolia, China. Alcheringa 40, XX–XX. ISSN 0311-5518.

Two new species of Itaphlebia Sukatsheva, 1985, Itaphlebia longiovata and I. amoena (Nannochoristidae Tillyard, 1917), are described and illustrated from the Middle Jurassic Jiulongshan Formation of Daohugou, Inner Mongolia, China. Previously described Middle Jurassic nannochoristid genera, Chrysopanorpa Ren in Ren et al., 1995 and Protochoristella Sun, Ren & Shih, 2007b, together with Stylopanorpodes and Netropanorpodes Sun, Ren & Shih, 2007a (originally assigned to Mesopanorpodidae) are revised and considered to be synonyms of Itaphlebia. The following tentative species synonymies are proposed: Protochoristella formosa and Stylopanorpodes eurypterus = Itaphlebia ruderalis (Ren in Ren et al., 1995), comb. nov.; Netropanorpodes sentosus = I. jeniseica Novokshonov, 1997a, syn. nov.; and Protochoristella polyneura = I. multa Novokshonov, 1997a, syn. nov. Netropanorpodes decorosus is transferred to Itaphlebia. These new species, new material and the new combinations broaden the diversity of the Itaphlebia in mid-Mesozoic ecosystems and provide new characters enabling amendment of the generic diagnosis.

YiZi Cao [], ChungKun Shih [] and Dong Ren [], College of Life Sciences, Capital Normal University, Xisanhuanbeilu 105, Haidian District, Beijing, PR China 100048; Alexei Bashkuev [], Borissiak Paleontological Institute, Russian Academy of Sciences, Profsoyuznaya st. 123, Moscow 117997, Russia.  相似文献   

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Current research themes relating to prehistoric Central Asian pastoralism are discussed, and the Neolithic to Bronze archaeological sequence in Kazakhstan is briefly outlined. The results of new faunal analyses of six later Bronze Age sites in Central and Northern Kazakhstan are presented. These studies are based upon the analysis of 63,529 bone fragments, of which 27,023 were identifiable to species and element. These assemblages are compared with 16 other sites in Central and Northern Kazakhstan, and the Trans-Ural region. The herd structures at the final Bronze Age site of Kent are discussed in detail. Analyses of absorbed lipid residues from four sites are also presented. In total, 140 pottery sherds were analysed, of which 73 provided sufficient residues for stable isotope ratio determinations. It is concluded that species proportions are highly variable regionally. Cattle are most prevalent in the forest steppe zone, whilst caprines become more common in semi-arid steppe regions. Proportions of horse are particularly variable, even within environmentally similar areas. Lipid residue results indicate the high prevalence of ruminant dairy products in pottery vessels, whilst faunal data from Kent suggests that cattle husbandry might have been particularly focussed on milk, in comparison with sheep and goats. The significance of horses within prehistoric pastoralism is discussed.  相似文献   
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The Trailer Park Boys series has received academic attention, much of which has been overtly critical. This study utilizes Gibson-Graham’s diverse economies framework to evaluate the show and its film adaptations. It argues that the show exemplifies alternative and informal economic practices which include alternative (non-capitalistic) businesses; substitute employee payment modes; alternative currencies; unpaid labor; and varying non-market practices, the most common being theft. These resident-led practices aid characters with multiple identities and worker roles in surviving a life bound by limited opportunity of formal work. In chorus with illegal and legal economic schemes, the community economy of Sunnyvale Trailer Park stimulates ethical decision-making in character interactions and in decision-making around topics such as surplus labor and profit management. Ecologically, various characters have reconstituted their relationship with their waste-filled area of residence, and some have gone as far as to provide provisional public goods to other park residents.  相似文献   
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At the height of the Cold War, in the 1950s, the process of parallel invention of masers and lasers took place on the opposing sides of the Iron Curtain. While the American part of the story has been investigated by historians in much penetrating detail, comparable Soviet developments were described more superficially. This study aims at, to some extent, repairing this discrepancy by analyzing the Soviet path towards the maser from a comparative angle. It identifies, on the one hand, significant differences between the two projects regarding their heuristics, the relationship between theory and experiment, grounding in different academic cultures, and the resulting conceptualization of the maser principle. At the same time, the case also illustrates more fundamental transformations in the practices of postwar research that can be characterized as a convergence between the Soviet and the American science of the period.  相似文献   
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