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421.
Timekeeping in the honey bee colony: integration of circadian rhythms and division of labor 总被引:1,自引:0,他引:1
Darrell Moore Jennifer E. Angel Iain M. Cheeseman Susan E. Fahrbach Gene E. Robinson 《Behavioral ecology and sociobiology》1998,43(3):147-160
The daily patterns of task performance in honey bee colonies during behavioral development were studied to determine the
role of circadian rhythmicity in age-related division of labor. Although it is well known that foragers exhibit robust circadian
patterns of activity in both field and laboratory settings, we report that many in-hive tasks are not allocated according
to a daily rhythm but rather are performed 24 h per day. Around-the-clock activity at the colony level is accomplished through
the performance of some tasks by individual workers randomly with respect to time of day. Bees are initially arrhythmic with
respect to task performance but develop diel rhythmicity, by increasing the occurrence of inactivity at night, prior to becoming
foragers. There are genotypic differences for age at onset of rhythmicity and our results suggest that these differences are
correlated with genotypic variation in rate of behavioral development: genotypes of bees that progressed through the age polyethism
schedule faster also acquired behavioral rhythmicity at an earlier age. The ontogeny of circadian rhythmicity in honey bee
workers ensures that essential in-hive behaviors are performed around the clock but also allows the circadian clock to be
engaged before the onset of foraging.
Received: 6 October 1997 / Accepted after revision: 28 March 1998 相似文献
422.
High relatedness and inbreeding in two species of haplodiploid eusocial thrips (Insecta: Thysanoptera) revealed by microsatellite analysis 总被引:1,自引:0,他引:1
Relatedness and inbreeding coefficients were estimated for Oncothrips tepperi and O. habrus, two species of eusocial gall-forming thrips, using data from two microsatellite loci. Relatedness between sets of individuals
(sexes and castes) for O. tepperi ranged from 0.5 to 0.85 and for O. habrus estimates were centered around 0.5. Multiple mating in O. habrus was implicated in lowering relatedness within a gall. We estimated the inbreeding coefficient to be 0.38 for both species,
the highest estimates known for eusocial insects. Our findings imply that high relatedness and inbreeding are important for
the evolution and form of social behavior in Australian gall-forming Thysanoptera.
Received: 14 November 1997 / Accepted after revision: 14 March 1998 相似文献
423.
The relation of age to division of labor was assessed in a primitively eusocial wasp, Ropalidia marginata. The performance of four functionally significant tasks was analyzed. It was found that age has a definite correlation with
division of labor, since wasps performed tasks in a distinct sequence in their life with successive tasks being initiated
at significantly older ages. Age of a wasp was measured in absolute terms and also relative to other individuals in the colony.
Probability of performance of a given task relative to other tasks (PTP) and absolute rates at which tasks were performed
per unit time (FTP) both showed clear age-dependent patterns, confirming the association of age with division of labor. The
proportion of variance explained for both PTP and FTP was significantly higher with relative age than with absolute age. Interindividual
interactions were found to be a potential mechanism through which wasps can determine their relative age. The advantages of
work organization depending on relative age and the constraints imposed by absolute age are discussed.
Received: 2 April 1997 / Accepted after revision: 20 July 1997 相似文献
424.
F. Stuart Chapin III Elke U. Weber Elena M. Bennett Reinette Biggs Jeroen van den Bergh W. Neil Adger Anne-Sophie Crpin Stephen Polasky Carl Folke Marten Scheffer Kathleen Segerson John M. Anderies Scott Barrett Juan-Camilo Cardenas Stephen R. Carpenter Joern Fischer Nils Kautsky Simon A. Levin Jason F. Shogren Brian Walker James Wilen Aart de Zeeuw 《Ambio》2022,51(9):1907
Transformation toward a sustainable future requires an earth stewardship approach to shift society from its current goal of increasing material wealth to a vision of sustaining built, natural, human, and social capital—equitably distributed across society, within and among nations. Widespread concern about earth’s current trajectory and support for actions that would foster more sustainable pathways suggests potential social tipping points in public demand for an earth stewardship vision. Here, we draw on empirical studies and theory to show that movement toward a stewardship vision can be facilitated by changes in either policy incentives or social norms. Our novel contribution is to point out that both norms and incentives must change and can do so interactively. This can be facilitated through leverage points and complementarities across policy areas, based on values, system design, and agency. Potential catalysts include novel democratic institutions and engagement of non-governmental actors, such as businesses, civic leaders, and social movements as agents for redistribution of power. Because no single intervention will transform the world, a key challenge is to align actions to be synergistic, persistent, and scalable. 相似文献
425.
Coal mining and the resource community cycle: A longitudinal assessment of the social impacts of the Coppabella coal mine 总被引:3,自引:0,他引:3
Two social impact assessment (SIA) studies of Central Queensland's Coppabella coal mine were undertaken in 2002–2003 and 2006–2007. As ex post studies of actual change, these provide a reference point for predictive assessments of proposed resource extraction projects at other sites, while the longitudinal element added by the second study illustrates how impacts associated with one mine may vary over time due to changing economic and social conditions. It was found that the traditional coupling of local economic vitality and community development to the life cycle of resource projects—the resource community cycle—was mediated by labour recruitment and social infrastructure policies that reduced the emphasis on localised employment and investment strategies, and by the cumulative impacts of multiple mining projects within relative proximity to each other. The resource community cycle was accelerated and local communities forced to consider ways of attracting secondary investment and/or alternative industries early in the operational life of the Coppabella mine in order to secure significant economic benefits and to guard against the erosion of social capital and the ability to cope with future downturns in the mining sector. 相似文献
426.
Testing the limits of social resilience in ant colonies 总被引:4,自引:0,他引:4
Sarah J. Backen A. B. Sendova-Franks Nigel R. Franks 《Behavioral ecology and sociobiology》2000,48(2):125-131
Social resilience is the ability of Leptothorax ant colonies to re-assemble after dissociation, as caused, for example, by an emigration to a new nest site. Through social
resilience individual workers re-adopt their spatial positions relative to one another and resume their tasks without any
time being wasted in worker respecialisation. Social resilience can explain how an efficient division of labour can be maintained
throughout the trials and tribulations of colony ontogeny including the, often substantial, period after the queen dies when
the ability to conserve worker social relationships may be essential for efficiency to be maintained. The mechanism underlying
social resilience is, therefore, expected to be robust even in the absence of many of the colony’s components, such as the
queen, the brood and even a large proportion of the workers. Such losses are likely, given the ecology of this genus. Using
sociotomy experiments, we found that social resilience can occur in the absence of the queen. Furthermore, the spatial component
of social resilience can occur even when the queen, the brood, as well as a large proportion of the workers, are all absent
simultaneously and hence many of the tasks are missing. We conclude, therefore, that social resilience is indeed robust. This
does not, however, preclude worker flexibility in response to changes in task supply and demand. We propose a possible sorting
mechanism based on worker mobility levels which might explain the robustness underlying this phenomenon.
Received: 25 October 1999 / Accepted: 1 April 2000 相似文献
427.
We used interdemic variation in the tendency to form mixed-species groups to examine the costs and benefits of association
among the primates of Kibale National Park, Uganda. A year-long survey of six sites revealed that the amount of time that
the five common diurnal primates [red colobus (Procolobus
tephrosceles), black-and-white colobus (Colobus
guereza), redtail monkeys (Cercopithecus
ascanius), blue monkeys (Cercopithecus
mitis), and grey-cheeked mangabeys (Lophocebus
albigena)] spent in mixed-species groups varied dramatically among sites. In many cases, the proportion of time that species associated
was positively related to their densities. By using detailed behavioral observations of redtail monkeys and red colobus made
over 4 years (2660 h) at four sites, we were able to reject the null hypothesis that associations occur by chance for only
one of four sites. However, a correlative approach exploring the costs and benefits of association suggests that ecological
variables do influence association patterns. We found that redtail monkeys and red colobus overlapped in diet (19.2% of their
foraging effort) and traveled further when in mixed-species groups than when alone. Having demonstrated this, we examined
the applicability of the ecological constraints model for predicting the proportion of the time spent in mixed-species groups
based on food availability. For this analysis we concentrated on red colobus from the site with 35 months of observation and
demonstrated that their tendency to be in mixed- species groups was related to food availability. We used two methods to examine
if mixed-species associations function to decrease predation risk. First, chimpanzees are known to prey heavily on red colobus,
but rarely kill other primates. The time red colobus spent in mixed-species groups was correlated to chimpanzee density, but
it was not for the other monkey species, suggesting that mixed-species groups serve to decrease predation risk. Second, when
red colobus groups contain more infants and are presumably at the greatest risk of predation, they form mixed-species groups
most often. These results demonstrate that the costs and benefits of mixed-species associations vary dramatically over small
spatial and temporal scales. If such variation is generally the case, then studies conducted at different locations or different
times could easily highlight the importance of difference selective agents in favoring mixed-species associations.
Received: 10 February 1999 / Received in revised form: 16 September 1999 / Accepted: 2 October 1999 相似文献
428.
We investigated the influence of known correlates of parasitism, namely fish density, body size and social behaviour, on three
highly variable aspects of the interactions between cleaning gobies (Elacatinus spp.) and their clients, on a Barbadian coral reef. We specifically considered (1) variability in client visit rate to cleaning
stations, (2) cleaning goby preference for specific clients and (3) variation in the time spent cleaning by cleaners. Using
phylogenetically independent contrasts, we found that client species that were abundant on the reef visited cleaning stations
more often than rarer client species. This could be due to the positive relationship between ectoparasite load and client
density, or alternatively may simply reflect the frequency of contact between cleaners and clients. Cleaning gobies spent
more time cleaning large-bodied clients, which usually have higher ectoparasite loads, although cleaning goby preference for
clients was influenced by none of the correlates of client parasitism. Overall, factors assumed to correlate with ectoparasite
load had a limited influence on the variability observed in the interactions between cleaning gobies and their clients.
Received: 27 October 1999 / Received in revised form: 11 January 2000 / Accepted: 24 January 2000 相似文献
429.
China’s government is now promoting the Nomad Sedentarization Project (NSP) in large areas of grassland as a solution for ecological restoration and poverty alleviation. To examine the effects of this policy, we conducted in-depth interviews at two of the project’s sites and examined the social and ecological systems at village, county, and catchment scales in Jinghe County of Xinjiang. We found that (1) the NSP in one village greatly improved the household standard of living and changed their resource utilization modes; (2) the success in this village can be attributed to resources imported from the social and ecological systems at larger scales, and could not be repeated in a second nearby village with different constraints; and (3) the NSP is poorly adapted to local ecosystem characteristics, and may therefore have negative impacts at larger scales. To avoid these problems, holistic assessments are necessary to judge the NSP’s impacts on social and ecological systems at multiple scales, and the program must be implemented cautiously to account for the potential risks in ecologically vulnerable areas. 相似文献
430.
Hong Wang 《中国人口.资源与环境(英文版)》2016,14(2):96-104
Corporate Environmental Responsibility (CER) is the subsystem of Corporate Social Responsibility (CSR), which continues to increase prominence in the global economy. Nowadays, CER becomes more important in corporate sustainable development. Based on Carroll’s pyramid mode of CSR, this article explores the systematic feature of CER. From a systematic perspective, it sorts out its elements, structure, function, and principles of CER. And the four levels of economic, legal, ethical, and charitable structure are emphasized. With these considerations interpreted into practice, success will be achieved in potential cost savings, technological innovation, increased public acceptance, and better relations with governments. 相似文献