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1.
Understanding the social organization of group‐living organisms is crucial for the comprehension of the underlying selective mechanisms involved in the evolution of cooperation. Division of labour and caste formation is restricted to eusocial organisms, but behavioural asymmetries and reproductive skew is common in other group‐living animals. Permanently, social spiders form highly related groups with reproductive skew and communal brood care. We investigated task differentiation in nonreproductive tasks in two permanently and independently derived social spider species asking the following questions: Do individual spiders vary consistently in their propensity to engage in prey attack? Are individual spiders' propensities to engage in web maintenance behaviour influenced by their previous engagement in prey attack? Interestingly, we found that both species showed some degree of task specialization, but in distinctly different ways: Stegodyphus sarasinorum showed behavioural asymmetries at the individual level, that is, individual spiders that had attacked prey once were more likely to attack prey again, independent of their body size or hunger level. In contrast, Anelosimus eximius showed no individual specialization, but showed differentiation according to instar, where adult and subadult females were more likely to engage in prey attack than were juveniles. We found no evidence for division of labour between prey attack and web maintenance. Different solutions to achieve task differentiation in prey attack for the two species studied here suggest an adaptive value of task specialization in foraging for social spiders.  相似文献   
2.
While unauthorized immigration has existed in the USA since the inception of immigration laws in the early twentieth century, ‘illegality’ did not become a central concern in mainstream debate until the late 1970s. Existing scholarship has developed two lines of argument to explain the salience of illegality: a state-centred approach that sees bureaucrats pushing forth the category, and a ‘bottom-up’ approach that emphasizes the grass-roots activism of restrictionist organizations effectively disguising their nativism by appealing to law and order. The data collected here builds on but complicates the state-centred explanation, and points away from the ‘bottom-up’ approach. I locate a critical juncture in the immigration debate during the early 1970s and argue that the shift towards the focus on illegality as a point of concern was due to an alignment of interests that brought an array of civil society organizations commonly understood as progressive to coincide with sectors of the bureaucracy.  相似文献   
3.
States often ethnicize ethnic groups for their own purposes. In doing so, however, they unleash contradictory processes. While the state facilitates the integration of individuals into modern state structures on the basis of personal achievement, it will also traditionalize collective identity by promoting a recognized leader or headman. Over time ethnic reformers will challenge such state ethnicization and attempt to organize the community to achieve more autonomy, using state legislation to achieve these reforms. Paradoxically, this attempt, if successful, will not only encroach upon state power but also curtail the choice of the individual in the ethnic group to define his or her own ethnicity. The following article analyses the Israeli Druze's relationship to the State of Israel and the controversy among the Druze over the group's international organization. It analyses at what point state ethnicization gives way to ethnic autonomy at the expense of state power, and explores its implications on the development of civil society within the ethnic community. The diminution of state ethnicization in a democracy need not necessarily entail the empowerment of the ethnic group but rather the individual who belongs to it.  相似文献   
4.
This article identifies the phenomenon of ethnic civil society activism as mobilization that seeks to empower an ethnic community and challenges the institutional order. The case of the Palestinian Arab minority in Israel is discussed and is used to reveal the conditions under which disaffected minorities pursue the path of ethnic civil society. The study finds that an analytical framework that stresses the mutability of state structures and changes in broader state-society relations provides a better explanation than existing theories of ethnic conflict. State-society characteristics conducive to this type of mobilization are a well-institutionalized state that can prevent deviation from the state's foundational rules and a counterbalanced dispersion of authority that limits regime capacity to control society.  相似文献   
5.
This symposium on my book, The Specter of Race: How Discrimination Haunts Western Democracy (Princeton, 2018) provides an opportunity to engage specialists in classical and modern political theory and philosophy, comparative racial and ethnic politics, and political sociology who have provided commentary on different aspects of the two overarching arguments intertwined in The Specter of Race; how students of democracy have largely ignored how racial and ethno-national hierarchy has been historically tethered to its practice , and how students of comparative politics have, for the most part, ignored how these hierarchies have informed the very development of modern democracies.  相似文献   
6.
The field of reproductive medicine witnessed a breakthrough in September 2014 with the first successful live birth post uterine transplantation. This success represents the culmination of decades' worth of research on infertility and reproductive medicine. This subject of infertility gathers special attention in the Middle East, as childbearing is given paramount importance in the family unit. And as with any new medical advancement, Middle Eastern people look to their religious authorities for guidance. This paper describes the various ethical quandaries related to uterine transplantation, from a perspective of the religious and societal factors that are unique to the Middle East, and embeds them within the conversation of its alternative solutions.  相似文献   
7.
IntroductionColorectal cancer (CRC) screening generally starts screening by the age of 50 based on guidelines. Lately however, a U.S. guideline recommended to start CRC screening from age 45 and, very recently, two studies were published that addressed young-onset in Europe (in part) (Vuik et al., 2019; Araghi et al., 2019).Materials and MethodsFlemish CRC incidence and mortality data contextualise trend results for age groups under 50 and what the implications could be for practice.ResultsCRC incidence rates showed considerable variability over a 12-year period without a clear increase in disease burden for the age group 45–49 in Flanders. In several age groups under 39 an increasing incidence trend was visible for both genders. Data was analysed in a period where no CRC screening was present in Flanders.DiscussionDecreasing the target age for the Flemish CRC screening does not seem to be straightforward and primary prevention should be considered more prominently.  相似文献   
8.
In this article we present the activities of the Ontology Working Group (OWG) under the Metabolomics Standards Initiative (MSI) umbrella. Our endeavour aims to synergise the work of several communities, where independent activities are underway to develop terminologies and databases for metabolomics investigations. We have joined forces to rise to the challenges associated with interpreting and integrating experimental process and data across disparate sources (software and databases, private and public). Our focus is to support the activities of the other MSI working groups by developing a common semantic framework to enable metabolomics-user communities to consistently annotate the experimental process and to enable meaningful exchange of datasets. Our work is accessible via a public webpage and a draft ontology has been posted under the Open Biological Ontology umbrella. At the very outset, we have agreed to minimize duplications across omics domains through extensive liaisons with other communities under the OBO Foundry. This is work in progress and we welcome new participants willing to volunteer their time and expertise to this open effort. See the MSI Ontology Working Group website for a complete list of members and contributors. Web URL:  相似文献   
9.
If a social‐living animal has a long life span, permitting different generations to co‐exist within a social group, as is the case in many primate species, it can be beneficial for a parent to continue to support its weaned offspring to increase the latter's survival and/or reproductive success. Chimpanzees have an even longer period of dependence on their mothers' milk than do humans, and consequently, offspring younger than 4.5–5 years old cannot survive if the mother dies. Most direct maternal investments, such as maternal transportation of infants and sharing of night shelters (beds or nests), end with nutritional weaning. Thus, it had been assumed that a mother's death was no longer critical to the survival of weaned offspring, in contrast to human children, who continue to depend on parental care long after weaning. However, in theory at least, maternal investment in a chimpanzee son after weaning could be beneficial because in chimpanzees' male‐philopatric society, mother and son co‐exist for a long time after the offspring's weaning. Using long‐term demographic data for a wild chimpanzee population in the Mahale Mountains, Tanzania, we show the first empirical evidence that orphaned chimpanzee sons die younger than expected even if they lose their mothers after weaning. This suggests that long‐lasting, but indirect, maternal investment in sons continues several years after weaning and is vital to the survival of the sons. The maternal influence on males in the male‐philopatric societies of hominids may be greater than previously believed. Am J Phys Anthropol, 153:139–143, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
10.
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