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81.
If a forager bee returns to her hive laden with high-quality nectar but then experiences difficulty finding a receiver bee to unload her, she will begin to produce a conspicuous communication signal called the tremble dance. The context in which this signal is produced suggests that it serves to stimulate more bees to function as nectar receivers, but so far there is no direct evidence of this effect. We now report an experiment which shows that more bees do begin to function as nectar receivers when foragers produce tremble dances. When we stimulated the production of tremble dances in a colony and counted the number of bees engaged in nectar reception before and after the period of intense tremble dancing, we found a dramatic increase. In two trials, the number of nectar receivers rose from 17% of the colony’s population before tremble dancing to 30–50% of the population after the dancing. We also investigated which bees become the additional nectar receivers, by looking at the age composition of the receiver bees before and after the period of intense tremble dancing. We found that none of the bees recruited to the task of nectar reception were old bees, most were middle-aged bees, and some were even young bees. It remains unclear whether these auxiliary nectar receivers were previously inactive (as a reserve supply of labor) or were previously active on other tasks. Overall, this study demonstrates that a honey bee colony is able to rapidly and strongly alter its allocation of labor to adapt to environmental changes, and it further documents one of the communication mechanisms underlying this ability. Received: 31 May 1996/Accepted after revision: 9 August 1996  相似文献   
82.
This essay proposes a heuristic conservation between the emerging field of environmental communication and the “crisis discipline” of conservation biology in order to generate a set of ethical postulates for research, teaching, and professional consultation. To the extent that social/symbolic representations of “environment” embody interested orientations, such discourses potentially constrain and/or enable societal responses to environmental signals, including signs of ecological crises. The essay argues that, implicit in this and other functional premises, lies a principal ethical duty of environmental communication: the obligation to enhance the ability of society to respond appropriately to environmental signals relevant to the well-being of both human communities and natural biological systems.  相似文献   
83.
As corporations seek to appeal to environmentally conscious stakeholders, advertisements containing environmental claims have become increasingly prominent. A corporation's desire for an enhanced corporate reputation, combined with lenient environmental advertising regulation, has created the perfect environment for corporations to use—and misuse—environmental claims, resulting in “greenwashing.” Defined as the act of disseminating disinformation to consumers regarding the environmental practices of a company or the environmental benefits of a product or service, greenwashing occurs around the world. This study is a cross-national content analysis of 247 print ads from 84 issues of mainstream magazines from the United States and United Kingdom. Three-fourths (75%) of the ads analyzed contained one or more aspects of greenwashing. Firms advertising in US magazines were significantly more likely to employ misleading/deceptive environmental claims than UK firms and magazines. These findings suggest that without increased environmental advertisement regulation, greenwashing will persist as a disingenuous means for corporate reputation enhancement.  相似文献   
84.
Effective communication is essential to the success of collaborative ecosystem management projects. In this paper, we investigated the dynamics of the Interior Columbia Basin Ecosystem Management Projects (ICBEMP) cross-disciplinary integration process in the assessment phase. Using a case study research design, we captured the rich trail of experience through conducting in-depth interviews and collecting information from internal and public documents, videos, and meetings related to the ICBEMP. Coding and analysis was facilitated by a qualitative analysis software, NVivo. Results include the range of internal perspectives on barriers and facilitators of cross-disciplinary integration in the Science Integration Team (SIT). These are arrayed in terms of discipline-based differences, organizational structures and activities, individual traits of scientists, and previous working relationships. The ICBEMP organization included a team of communication staffs (CT), and the data described the CT as a mixed group in terms of qualifications and educational backgrounds that played a major role in communication with actors external to the ICBEMP organization but a minor one in terms of internal communication. The data indicated that the CT-SIT communication was influenced by characteristics of actors and structures related to organizations and their cultures. We conclude that the ICBEMP members may not have had a sufficient level of shared understanding of central domains, such as the task at hand and ways and timing of information sharing. The paper concludes by suggesting that future ecosystem management assessment teams use qualified communications specialists to design and monitor the development of shared cognition among organization members in order to improve the effectiveness of communication and cross-disciplinary integration.  相似文献   
85.
Is recycled water use risky? An Urban Australian community’s perspective   总被引:1,自引:0,他引:1  
The emergence of a global water crisis has seen the necessity for a sustainable approach to water management. Policies directed towards water recycling have been implemented in many regions of the world. In Australia, prolonged drought conditions in most major cities during the past decade have led to serious national calls for less drinking water to be used (Prime Minister’s Science Engineering and Innovation Council, 2003), and a strategic policy response from many State Governments, including bold targets for water recycling. A key consideration to the realisation of these policies is greater understanding of community attitudes to recycled water use, without which, a number of recycled water projects have failed (Hurlimann and McKay, 2004). Despite the critical nature of community attitudes, little research has been conducted, especially in relation to perception of risk, which has been found to be critical in the adoption of new technologies (Cvetkovich and Lofstedt, 1999). This paper investigates an urban Australian community’s perception of risk involved with using recycled water. Key findings include: perception of risk increased as the use of recycled water became increasingly personal. Perception of risk was significantly negatively related to trust, perception of fairness and information. Trust in the Water Authority to manage risk was significantly related to perception of trust, communication and integrity of the Authority.  相似文献   
86.
基于交通文化的交通安全策略   总被引:9,自引:4,他引:9  
以往对于交通安全的研究 ,很少有人从交通文化的深度进行分析 ,而对交通文化的研究确实具有现实意义和深远的战略价值。笔者针对这一问题 ,在阐述了交通文化的定义、特征的基础上 ,构建了交通文化系统的结构 ,说明了交通文化与交通安全的关系 ,提出了基于交通文化的驾驶员素质培训和安全教育、培养交通参与者交通安全意识、重视交通安全技术的研究和应用、加强道路交通管理和重视交通道德建设等交通安全策略。  相似文献   
87.
产学研结合是高职教育改革发展的必由之路。本文从通信专业的发展现状着手,详述了通信专业在校企合作方面所做的努力和取得的成果,并探讨了校企合作今后需努力的方向。  相似文献   
88.
We examined factors that determine the outcome of agonistic encounters between male pygmy swordtail fish. Xiphophorus nigrensis and X. multilineatus males formed dominance relationships based on body size in staged laboratory encounters. There was a significant negative correlation between size asymmetry and fight intensity, suggesting that males assessed size in the encounters. However, a significant proportion of the variation in fight intensity in contests that escalated to bites could not be explained by size asymmetry. Aggressive motivation may also influence the outcome of contests and could be assessed in agonistic encounters. Theory suggests that signals of aggressive intention will be evolutionarily stable if individuals can recognize opponents and encounter one another repeatedly. In addition, individual recognition is one way that dominance hierarchies can be maintained. Here we demonstrate that males from both species can recognize individuals. In addition, at least some X. nigrensis males were site-faithful in the field, suggesting males encounter the same opponents repeatedly.Communicated by G.M. Klump  相似文献   
89.
Summary. This article surveys early chemosensory mechanisms regulating behaviour in neonatal and juvenile domestic cats (Felis sylvestris catus). It aims to retrieve material from the available literature which may promote a better understanding of the semiochemical system that supports female-to-kitten exchanges. Studies dealing with the development of olfaction from birth through weaning are presented in three sections. The first aims at locating developmental periods suitable for applying analytical procedures combining behaviour and chemistry. The second section offers a survey of observational and experimental work related to the role of olfaction in the social and feeding behaviour of kittens before weaning. The final section traces the current knowledge on the odour sources and substrates that may be involved in early mother-kitten transactions.  相似文献   
90.
A central question in animal communication research concerns the reliability of animal signals. The question is particularly relevant to aggressive communication, where there often may be advantages to signaling an exaggerated likelihood of attack. We tested whether aggressive signals are indeed reliable signals of attack in song sparrows (Melospiza melodia). We elicited aggressive signaling using a 1-min playback on a male’s territory, recorded the behavior of the male for 5 min, and then gave him the opportunity to attack a taxidermic mount of a song sparrow associated with further playback. Twenty subjects attacked the mount and 75 did not. Distance to the speaker was a significant predictor of attack for both the initial recording period and the 1 min before attack. For the initial recording period, none of the measures of singing behavior that we made was a significant predictor of attack, including song-type matching, type-switching frequency, and song rate. For the 1-min period immediately before attack, only the number of low amplitude “soft songs” was a significant predictor of attack. Although most aggressive signals contained little information on attack likelihood, as some models suggest should be the case, the unreliability of these signals was not caused by convergence of individuals on a single signaling strategy, as those models argue should occur.  相似文献   
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