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201.
Within-nest temporal polyethism in the honey bee 总被引:1,自引:1,他引:0
Brian R. Johnson 《Behavioral ecology and sociobiology》2008,62(5):777-784
A well-regulated division of labor has been one of the core adaptations leading to the success of the social insects. Honeybee
division of labor has been classically viewed as a sequence of age-related changes in task performance. Kolmes questioned
this view arguing that his studies did not support the existence of any age-related within-nest specialization. To resolve
this controversy, Kolmes and Seeley conducted a joint study with mixed results. They found support for a cell cleaning caste,
but diverged on whether their results supported distinct nursing and middle age castes. In this paper, I follow up on their
work to resolve the question of caste number in within-nest honey bees. To determine whether nurses (typically aged 4–12 days)
and middle-aged bees (aged 12–20 days) have distinct task repertoires, I conducted focal animal observations on a large number
of workers in both age groups working within the same nests at the same time. The results support their being two castes of
within-nest bees. Young bees specialized on brood care tasks, while middle-aged bees specialized on nectar processing and
nest maintenance. Middle-aged bees were observed caring for brood in less than 1% of the observations. Moreover, both castes
exhibited movement patterns that correspond to the traditional view that nurses stay within the broodnest, while middle-aged
bees move around a great deal in search of work throughout the nest. A review of studies conducted since the debate of Seeley
and Kolmes supports the reliability of these results. This work has relevance for proximate models of temporal polyethism,
as it is often assumed by such models that there is only one within-nest caste in the honeybee. 相似文献
202.
Facultative joint colony founding by social insects provides opportunities to analyze the roles of genetic and ecological
factors in the evolution of cooperation. Although cooperative nesting is observed in range of social insect taxa, the most
detailed studies of this behavior have been conducted with Hymenoptera (ants, bees, and wasps). Here, we show that foundress
associations in the haplodiploid social thrips Dunatothrips aneurae (Insecta: Thysanoptera) are most often comprised of close relatives (sisters), though groups with unrelated foundresses are
also found. Associations among relatives appear to be facilitated by limited female dispersal, which results in viscous population
structure. In addition, we found that per capita productivity declined with increasing group size, sex ratios were female-biased,
and some female offspring apparently remained in their natal domicile for some time following eclosion. D. aneurae thus exhibits a suite of similarities with eusocial Hymenoptera, providing evidence for the convergent evolution of associated
social and life-history traits in Hymenoptera and Thysanoptera. 相似文献
203.
Anna Dornhaus Jo-Anne Holley Victoria G. Pook Gemma Worswick Nigel R. Franks 《Behavioral ecology and sociobiology》2008,63(1):43-51
Here, we study distribution of workload and its relationship to colony size among worker ants of Temnothorax albipennis, in the context of colony emigrations. We find that one major aspect of workload, number of items transported by each worker,
was more evenly distributed in larger colonies. By contrast, in small colonies, a small number of individuals perform most
of the work in this task (in one colony, a single ant transported 57% of all items moved in the emigration). Transporters
in small colonies carried more items to the new nest per individual and achieved a higher overall efficiency in transport
(more items moved per transporter and unit time). Our results suggest that small colonies may be extremely dependent on a
few key individuals. In studying colony organisation and division of labour, the amount of work performed by each individual,
not just task repertoire (which tasks are performed at all), should be taken into account. 相似文献
204.
Assessing carrying capacities of coastal areas in France 总被引:1,自引:0,他引:1
This paper provides the methodological framework for carrying capacity assessment through a set of indicators, as implemented
in a French case study. The approach aims to help the State and local governments of coastal areas facing population growth
and important touristic flows to undergo a local development strategy that does not imperil their territorial strategic resources.
This work shows how situations of dysfunction or saturation points have interlinked consequences on environmental, social
and economic resources, justifying a crosswise assessment. 相似文献
205.
Efficient and equitable design of marine protected areas in Fiji through inclusion of stakeholder‐specific objectives in conservation planning 下载免费PDF全文
Robert L. Pressey Natalie C. Ban Jorge G. Álvarez‐Romero Stacy Jupiter Vanessa M. Adams 《Conservation biology》2015,29(5):1378-1389
The efficacy of protected areas varies, partly because socioeconomic factors are not sufficiently considered in planning and management. Although integrating socioeconomic factors into systematic conservation planning is increasingly advocated, research is needed to progress from recognition of these factors to incorporating them effectively in spatial prioritization of protected areas. We evaluated 2 key aspects of incorporating socioeconomic factors into spatial prioritization: treatment of socioeconomic factors as costs or objectives and treatment of stakeholders as a single group or multiple groups. Using as a case study the design of a system of no‐take marine protected areas (MPAs) in Kubulau, Fiji, we assessed how these aspects affected the configuration of no‐take MPAs in terms of trade‐offs between biodiversity objectives, fisheries objectives, and equity in catch losses among fisher stakeholder groups. The achievement of fisheries objectives and equity tended to trade‐off concavely with increasing biodiversity objectives, indicating that it is possible to achieve low to mid‐range biodiversity objectives with relatively small losses to fisheries and equity. Importantly, the extent of trade‐offs depended on the method used to incorporate socioeconomic data and was least severe when objectives were set for each fisher stakeholder group explicitly. We found that using different methods to incorporate socioeconomic factors that require similar data and expertise can result in plans with very different impacts on local stakeholders. 相似文献
206.
Mark A. Ferguson Nyla R. Branscombe Katherine J. Reynolds 《Journal of environmental psychology》2011,31(4):275-281
The present research examines the effects of intergroup comparison on willingness to perform sustainable behavior. In Experiment 1, university students compared current students with past or future students, and then completed measures of willingness to perform sustainable behavior. Participants who compared to past students reported more willingness to perform sustainable behavior than those who compared to future students. In Experiment 2, university students again compared current students with past or future students and completed measures of sustainable beliefs and willingness to perform sustainable behavior. Participants who compared to past students reported more willingness to perform sustainable behavior than those who compared to future students. This effect was mediated by strengthened sustainable beliefs. The results show that intergroup comparison can be strategically employed to promote motivation to perform sustainable behavior. 相似文献
207.
This paper presents the results from a survey on experts’ attitudes towards the development of CCS technologies in Spain. This is the first study carried out in Spain intending to report an empirical analysis of stakeholder perceptions on the risks, challenges and barriers facing CCS deployment. Results show a positive attitude towards CCS implementation in Spain. Experts are concerned about the suitability of storage sites, safety and capture costs. They tend to support CCS as a bridging solution to climate change, and have a general low level of perceived risk from CCS. Experts’ risk perception is influenced, to some extent, by general values and beliefs as well as by sociodemographics and, to a lesser extent, by group membership. 相似文献
208.
综述了影响肾移植患者心理健康的原因以及社会支持与心理健康的相关性,并探讨通过社会支持提高肾移植患者心理健康水平的途径.从而提示护理工作者在工作中应尽可能调动肾移植患者本人、家庭成员及社会的主观能动性,以提高肾移植患者的心理健康水平. 相似文献
209.
Many cities' municipal governments have made some version of “sustainability” an explicit policy goal over the past two decades. Previous research has documented how the operationalisation and conceptualisation of sustainability in urban sustainability plans vary greatly among cities, particularly with respect to environmental justice. This article reports on whether and how large American cities incorporate environmental justice into their urban sustainability indicator projects. Our findings suggest that while there has been an increase in the number of cities incorporating environmental justice elements into sustainability plans since the early 2000s, their conceptualizations and implementations of sustainability remain highly constrained. The paucity of evaluative tools suggests that environmental justice efforts are potentially losing traction in public debate over macro-scale sustainability concerns (e.g. climate change) or the need for regionally competitive environmental amenities (e.g. parks). This paper concludes with suggestions for revising existing sustainability plans to better reflect environmental justice concerns. 相似文献
210.
ABSTRACTThis paper employs qualitative content analysis to assess 28 brownfield redevelopment plans produced as part of a US Environmental Protection Agency programme. The analysis framework followed the economic, ecological, and social equity dimensions of sustainable development. The findings illustrate that, in terms of economic dimensions, most plans discussed financing the overall project, but few mentioned site values or the pivotal cost of remediating brownfield sites or addressed questions related to liability, the transfer of ownership of sites, or the end use of remediated sites. In terms of ecological dimensions, while many plans suggested “green” uses of existing brownfields, few discussed the impacts of the plans on urban ecological issues or offered technical feasibility of remediating the sites. In terms of social equity dimensions, half of the plans described potential local jobs stemming from the proposed redevelopment, but many did not discuss the human impacts of remediating contaminated sites or the costs of doing nothing. Most plans mentioned community engagement methods but not their outcomes, making the degree to which the lessons gleaned from such engagement influenced the plans totally unclear. Despite the programme’s explicit focus on the nexus of environmental justice and local environments, many plans struggled to address the topic in favour of tackling broader economic, environmental, and equity issues. Overall, this paper contributes to the understanding of brownfield redevelopment planning by not only summarising and synthesising the tendencies of existing plans but also suggesting strategies to address areas in which current planning efforts fall short. 相似文献