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281.
Perttu Seppä Ignacio Fernández-Escudero Niclas Gyllenstrand Pekka Pamilo 《Behavioral ecology and sociobiology》2008,62(4):589-597
Establishment of new groups is an important step in the life history of a social species. Fissioning is a common mode not
only in group proliferation, for instance, as a regular part of the life cycle in the honey bee, but also when multiple females
reproduce in the same group, as in multiple-queen ant societies. We studied the genetic consequences of fissioning in the
ant Proformica longiseta, based on DNA microsatellites. In P. longiseta, new nests arise by fissioning from the old ones when they grow large, and the daughter nests consist of workers and queens
or queen pupae but never both. Our results show that fissioning is not entirely random with respect to kinship. Workers tend
to segregate along kin lines, but only when the initial relatedness in the parental nests is low. Workers in a daughter nest
also tend to be associated with closely related adult queens, whereas such an association is not detected between workers
and queen pupae. Most queens and workers are carried to the daughter nest by a specialized group of transporting workers,
suggesting active kin discrimination by them. Fissioning pattern in P. longiseta is different from that found in other social insects with regular fission (e.g., the honey bee, swarm-founding wasps), where
no fissioning along kin lines has been found. It does, however, resemble fissioning in another group of social animals: primates. 相似文献
282.
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
283.
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
284.
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
285.
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
286.
光助氧化技术在水处理中应用 总被引:5,自引:0,他引:5
对UV/H2O2技术、UV/O3技术、UV/O3/H2O2技术、photo—Fenton技术以及UV/TiO2技术进行了总结,对不同技术的原理、研究进展及应用进行了评述,并对今后光助氧化技术的研究方向提出了一些建议。 相似文献
287.
基于大数据的视角对1993—2013年我国国家社科基金旅游项目进行了全样本统计和研究,并采用SPSS17.0软件对项目负责人、负责人所在单位、单位所在省市进行了描述性分析和聚类分析,同时借助ROSTCM6软件对项目主题进行了语义网络分析,全面展示了国家社科基金旅游项目反映的我国旅游发展格局,系统认识和评价国家社科基金旅游项目对我国旅游研究的贡献有一定的指导作用。 相似文献
288.
Marco Caniato Mentore Vaccari Chettiyappan Visvanathan Christian Zurbrügg 《Waste management (New York, N.Y.)》2014,34(5):938-951
Assessing the strengths and weaknesses of a solid waste management scheme requires an accurate analysis and integration of several determining features. In addition to the technical aspects, any such system shows a complex interaction of actors with varying stakes, decision-making power and influence, as well as a favourable or disabling environment. When capitalizing on the knowledge and experience from a specific case, it is also crucial that experts do not “forget” or underestimate the importance of such social determinants and that they are familiar with the methods and tools to assess them. Social network analysis (SNA) and stakeholder analysis (SA) methods can be successfully applied to better understand actors’ role and actions, analyse driving forces and existing coordination among stakeholders, as well as identify bottlenecks in communication which affect daily operations or strategic planning for the future way forward. SNA and SA, appropriately adjusted for a certain system, can provide a useful integration to methods by assessing other aspects to ensure a comprehensive picture of the situation. This paper describes how to integrate SNA and SA in order to survey a solid waste management system. This paper presents the results of an analysis of On-Nuch infectious waste incinerator in Bangkok, Thailand. Stakeholders were interviewed and asked to prioritize characteristics and relationships which they consider particularly important for system development and success of the scheme. In such a way, a large quantity of information about organization, communication between stakeholders and their perception about operation, environmental and health impact, and potential alternatives for the system was collected in a systematic way. The survey results suggest that stakeholders are generally satisfied with the system operation, though communication should be improved. Moreover, stakeholders should be strategically more involved in system development planning, according to their characteristics, to prevent negative reactions. 相似文献
289.
Linley Chiwona-Karltun Franklin Amuakwa-Mensah Caroline Wamala-Larsson Salome Amuakwa-Mensah Assem Abu Hatab Nolwandle Made Nathan Kanuma Taremwa Lemayon Melyoki Lettice Kinunda Rutashobya Thulisile Madonsela Marna Lourens Wendy Stone Alfred R. Bizoza 《Ambio》2021,50(4):794
Like the rest of the world, African countries are reeling from the health, economic and social effects of COVID-19. The continent’s governments have responded by imposing rigorous lockdowns to limit the spread of the virus. The various lockdown measures are undermining food security, because stay at home orders have among others, threatened food production for a continent that relies heavily on agriculture as the bedrock of the economy. This article draws on quantitative data collected by the GeoPoll, and, from these data, assesses the effect of concern about the local spread and economic impact of COVID-19 on food worries. Qualitative data comprising 12 countries south of the Sahara reveal that lockdowns have created anxiety over food security as a health, economic and human rights/well-being issue. By applying a probit model, we find that concern about the local spread of COVID-19 and economic impact of the virus increases the probability of food worries. Governments have responded with various efforts to support the neediest. By evaluating the various policies rolled out we advocate for a feminist economics approach that necessitates greater use of data analytics to predict the likely impacts of intended regulatory relief responses during the recovery process and post-COVID-19. 相似文献
290.
Small hydropower (SHP) is promoted as a pro-poor renewable energy source that does not have the negative social impacts of large dams. This article challenges these claims, using data from a household survey in China’s upper Red River Basin. We find that SHP can fragment river systems in ways that reduce irrigation water availability, provoke changes to agricultural practices, and negatively impact river health. These social impacts of river fragmentation mainly occur in villages situated between a plant’s intake and outflow. The frequency of plant water diversions due to continued generation in the dry season significantly predicts all social impacts; installed capacity of the plant and the quality of the village’s irrigation infrastructure predict some impacts. Villages with strong local governance can negotiate with the plant to temporarily halt generation when irrigation water is needed, lessening social impacts. Our findings reveal that SHP plants are not as benign as they are made out to be; they must be built and managed according to community needs. 相似文献