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Franz Unger     
Ohne Zusammenfassung  相似文献   

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《Brittonia》1961,13(3):252-252
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《Cell》2011,147(3):481-483
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The reputation of Franz Boas as a scientist declined in the decades after his death in 1942, but his reputation as a champion of human rights and an opponent of racism remained intact. More recently, however, some writers have questioned the sincerity, the results, and the political implications of his anthropology and his work against racism and ethnocentrism. Others have been critical of his relations with colleagues and students such as Ella Deloria and Zora Neale Hurston. In this essay I discuss some of these claims and present a more positive view. Franz Boas was passionately and consistently concerned about human rights and individual liberty, freedom of inquiry and speech, equality of opportunity, and the defeat of prejudice and chauvinism. He struggled for a lifetime to advance a science that would serve humanity, and he was as much of a humanitarian in private as he was in public. [Boas, political struggles, human relations]  相似文献   

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Franz Boas was responsible for obtaining anthropometric data from approximately 27,000 subjects living around the turn-of-the-century. The subjects are of Native American, Siberian and European ancestry. These data have been entered into databases and are available for research. This paper describes the circumstances under which these data were collected and discusses their research potential.  相似文献   

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Since population-level variation in female mating preferences can shape intraspecific communication systems within the context of sexual selection it is essential to quantify these preferences and their sources of variation. We calculated individual female response functions for four male calling song traits in the field cricket Gryllus bimaculatus, by performing untethered phonotaxis measurements on a spherical locomotor compensator (Kramer treadmill). Firstly, we quantify the population-level sources of phonotactic variation and correct for factors that adversely affect this measurement. Secondly, we develop methodology for the characterisation of individual female phonotactic response functions suitable for population-level analyses and demonstrate the applicability of our method with respect to recent literature on Orthopteran acoustic communication. Phonotaxis towards a preferred stimulus on different occasions is highly repeatable, with lower repeatabilities away from the most preferred signal traits. For certain male signal traits, female preference and selectivity are highly repeatable. Although phonotactic response magnitude deteriorated with age, preference functions of females remained the same during their lifetimes. Finally, the limitations of measuring phonotaxis using a spherical locomotor compensator are described and discussed with respect to the estimation of the selectivity of female response.  相似文献   

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We introduce a method to transform wing venation data to a numerical form so that the venation pattern can be analysed and compared regardless of wing size and displacement of the pattern. We use the method for assessing the intraspecific variation and asymmetry within the individual of relative positions of forewing veins in ten species of elachistid moths. Both the intraspecific variation and intra-individual asymmetry were found to be greater than the differences frequently used as systematic characters on various levels within Elachistidae, and to some extent in other Lepidoptera. At least in Elachistidae, major alterations to the current classification will have to be made. Wing characters subject to intraspecific variation should not be used to delimit groups unless they are based on examination of population samples and supported by other characters.  相似文献   

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Benthic fauna of the deeper waters (50–320 m) of the Franz Josef Land archipelago sampled in August 1992 using standard western techniques is described and compared with earlier Russian studies of the archipelago. Three faunal assemblages are recognised at depth ranges between 50–150, 150–300, and >300 m depth. Their distributions are related to depth and to different water masses derived from a mixture of Barents Sea water entering from the south at intermediate depths (20–150 m), and Atlantic water from the north below 300 m. The recorded faunal diversity and biomass is as high as or higher than that from comparable Arctic and northern boreal areas. Comparisons are also made with a complimentary Russian survey in the same area using different techniques. The Russian work collected larger organisms most effectively, whereas the present work recorded the smaller taxa more efficiently. Russian surveys provide complementary data to western studies, but care must be taken when comparing studies as they reflect biases in sampling gear and scientific emphasis. These data intercalibrations are important as Russian archives contain a wealth of information that, if used correctly in association with western data sources, will be useful in environmental monitoring studies as human activities increase in the Eurasian Arctic. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

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