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51.
Cloning is widely considered only to be a biological discourse. Few, however, have paid attention to the cultural contexts that have made cloning conceivable. The relation between the biological and cultural considerations of cloning are revealed by the anxieties conjured up by the prospects of cloning human beings. By cloning we understand the reproduction of sameness which is deeply ingrained in the organization and reproduction of culture. The ease with which cloning has been taken up in contemporary thinking has been made possible by the widespread saturation of the normative assumption of socio-cultural sameness underpinning much of mainstream modern thinking around politics, law, education, management, aesthetics, the military and processes of production. We consider the cultural considerations regarding the reproduction of sameness and the implications of cloning for issues of social injustice. 相似文献
52.
The economic returns of bonding and bridging social capital for immigrant men in Germany 总被引:1,自引:0,他引:1
Bram Lancee 《Ethnic and racial studies》2013,36(4):664-683
Using longitudinal data, this paper analyses the effect of different forms of social capital on the likelihood of employment and the occupational status of first generation immigrant men in Germany. This allows me to examine to what extent social capital of the bonding and the bridging types yield different returns. The study considers how contacts with natives, co-ethnic ties and family-based social capital are beneficial to the economic position of immigrant men. Random effects and fixed effects models show that strong inter-ethnic ties are beneficial both for employment and occupational status. There is no effect of co-ethnic ties and family-based social capital. It is concluded that, when using panel data, bridging social capital contributes to a better economic position and bonding social capital does not. 相似文献
53.
54.
David Kyle 《Ethnic and racial studies》2013,36(2):422-446
This article examines the role of historical social resources in the development of a transnational trade diaspora of Ecuador's indigenous Otavalan merchants. The Otavalans are well known for their production of handicrafts, using pre-industrial and industrial technologies, and for their far-flung trips in search of foreign buyers. In this account, the role of 'social capital', typically defined as a 'public good', is highlighted to better gauge its usefulness to other migrant and indigenous groups. I conclude that the Otavalo case suggests that in-group 'social capital' is: (a) not sufficient or necessary for 'grass-roots' transnational entrepreneurship; (b) the political origins of an ethnic group's 'trust-worthiness' reveal a more diverse set of symbolic and cultural 'capitals', which may then be used by an emergent merchant class to gain financial capital for a business venture; and (c) 'globalization' notwithstanding, contemporary trade diasporas may rise and fall due to similar causal dynamics found among much older and ubiquitous 'cross-cultural trade diasporas'. 相似文献
55.
Etya Amsalem Hagai Shpigler Guy Bloch Abraham Hefetz 《Journal of insect physiology》2013,59(12):1250-1255
Bombus terrestris colonies go through two major phases: the “pre-competition phase” in which the queen is the sole reproducer and aggression is rare, and the “competition phase” in which workers aggressively compete over reproduction. Conflicts over reproduction are partially regulated by a group of octyl esters that are produced in Dufour’s gland of reproductively subordinate workers and protect them from being aggressed. However, workers possess octyl esters even before overt aggression occurs, raising the question of why produce the ester-signal before it is functionally necessary?In most insect societies, foragers show reduced aggression and low dominance rank. We hypothesize that ester production in B. terrestris is not only correlated with sterility but also with foraging, signaling cooperative behavior by subordinate workers. Such a signal helps to maintain social organization, reduce the cost of fights between reproductives and helpers, and increase colony productivity, enabling subordinates to gain greater inclusive fitness. We demonstrate that foragers produce larger amounts of esters compared to non-foragers, and that their amounts positively correlate with foraging efforts. We further suggest that task performance, potential fecundity, and aggression are interlinked, and that worker–worker interactions are involved in regulating foraging behavior.B. terrestris, being an intermediate phase between primitive and derived eusocial insects, provides an excellent model for understanding the evolution of early phases of eusociality. Our results, combined with those in primitively eusocial wasps, suggest that at early stages of social evolution, reproduction was regulated by a “primordial division of labor”, that comprised foragers and reproducers, which further evolved to a more complex division of labor, a hallmark of eusociality. 相似文献
56.
Recent research suggests that testosterone and cortisol jointly regulate dominance motivation and, perhaps, the status relationships that are affected by it. For this article, the results of six different studies of women's intercollegiate athletic competition were combined to give a sample size of almost ninety women for whom we had before- and after-competition values for salivary cortisol and testosterone for at least one and sometimes two competitions. For many of these women, we had surveys that allowed us to assess their status with teammates. In no matter what sport (soccer, softball, volleyball, and tennis) levels of salivary cortisol and testosterone increased when women participated in athletic competition. Salivary levels of C and T appear to rise in parallel during competition and increases in levels of one hormone are significantly related to increases in the other. Salivary levels of these hormones typically decreased for teammates who did not play but watched the competition from the sidelines. For women who played in two competitions, individual differences in the positive effect of competition on cortisol and testosterone were conserved from one competition to the next, affirming the personal consistency of endocrine responses to competition. Status with teammates was positively related to before-competition levels of testosterone, but only for women with relatively low before-competition levels of cortisol. This result provides novel support for the “dual-hormone hypothesis” as it relates to predicting social status in women's athletic teams — natural social groups of individuals who know each other and whose social hierarchy has evolved over the course of practice and play for at least one and, in some cases, several years of intercollegiate athletic competition. 相似文献
57.
Eduard T. Klapwijk Anne-Lise Goddings Stephanie Burnett Heyes Geoffrey Bird Russell M. Viner Sarah-Jayne Blakemore 《Hormones and behavior》2013
This article is part of a Special Issue “Puberty and Adolescence”. 相似文献
58.
An individual's position in a social hierarchy profoundly affects behavior and physiology through interactions with community members, yet little is known about how the brain contributes to status differences between and within the social states or sexes. We aimed to determine sex-specific attributes of social status by comparing circulating sex steroid hormones and neural gene expression of sex steroid receptors in dominant and subordinate male and female Astatotilapia burtoni, a highly social African cichlid fish. We found that testosterone and 17β-estradiol levels are higher in males regardless of status and dominant individuals regardless of sex. Progesterone was found to be higher in dominant individuals regardless of sex. Based on pharmacological manipulations in males and females, progesterone appears to be a common mechanism for promoting courtship in dominant individuals. We also examined expression of androgen receptors, estrogen receptor α, and the progesterone receptor in five brain regions that are important for social behavior. Most of the differences in brain sex steroid receptor expression were due to sex rather than status. Our results suggest that the parvocellular preoptic area is a core region for mediating sex differences through androgen and estrogen receptor expression, whereas the progesterone receptor may mediate sex and status behaviors in the putative homologs of the nucleus accumbens and ventromedial hypothalamus. Overall our results suggest sex differences and similarities in the regulation of social dominance by gonadal hormones and their receptors in the brain. 相似文献
59.
为探究不同地位的克氏原螯虾(Procambarus clakii)胜利者-失败者效应的稳定性。通过视频拍摄优势者和从属者在新的领域中各自与等重量级雄性螯虾连续遭遇战,统计胜负场数、格斗次数、时间、优势指数等多个参数。在与陌生对手的首次交战中,40个优势者中有23只螯虾取得了胜利,17只失败,胜负比例之间差异不显著;而从属者中获胜比例为18/40,与失败者的比例之间也没有差异,说明优势者和从属者之间原有的等级地位并不被陌生对手识别。在与陌生对手的第二次交战中,获胜的优势者中18/23的螯虾再次胜利,极显著高于失败的螯虾比例;获胜的从属者中,仅11/18的螯虾再次胜利,与失败者的比例之间不显著;而失败的优势者中,13/17的螯虾持续失败,失败的从属者中,17/22的螯虾持续失败,均显著高于获胜的比例,说明不同地位的螯虾胜利者-失败者效应稳定性不同,优势者的胜利者-失败者效应均比较稳定,而从属者的失败者效应稳定,胜利者效应并不稳定,一胜之后不能获得稳定、完全的二胜。对格斗次数、时间、优势指数等参数统计分析发现,胜利或失败的优势者以及从属者在格斗策略上有较大的差异。 相似文献
60.
Takashi Kuriwada 《Population Ecology》2016,58(1):147-153
Social isolation has often been reported to facilitate male aggressiveness in various animal species. If social isolation also escalates male aggressive behavior towards females, the mating success of the aggressive males will be low. This study evaluated the effect of social isolation on mating behavior in the field cricket Gryllus bimaculatus, which has traditionally been considered to be an asocial species. The results showed that social isolation from same-sex individuals enhanced male aggressiveness to females, and the mating success of aggressive males was reduced under the experimental conditions. More aggressive males exhibited a longer latency to court than less aggressive males. These results suggest that because male aggressiveness causes a delay in courtship, aggressive males may have reduced mating success. This demonstrated that social relationships are a critical factor affecting male mating success, even if the species is normally considered solitary. 相似文献