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331.
Climate change science can trace its origins back to the early 19th Century although interest really took off in the 1980s, when public interest and research activity proliferated as the potential negative effects of global warming became clear. The impacts of climate change on the marine environment was receiving little attention at this time, but in recent years has started to “catch up” both in terms of research activity and public and policy interest. In the UK, the Marine Climate Change Impacts Partnership (MCCIP) has played a key role in transferring the emerging evidence base on marine climate change impacts to decision makers through the development of climate change report cards. Since publishing its first card back in 2006, the MCCIP cards have become established as the principal source of marine climate change impacts evidence for policy makers in the UK, and similar approaches have been adopted elsewhere. Here we broadly describe how the climate change evidence base has evolved over time, with a focus on the marine evidence base, and the approach adopted in the UK by MCCIP to rapidly transfer this evidence to end users. The SIIRMS model developed by MCCIP to ensure integrity and independence in the scientific translation process is explored, along with wider lessons learnt along the way (e.g. about communicating uncertainty) and the impact MCCIP has had on informing decision making. 相似文献
332.
Peter M. Kappeler 《Behavioral ecology and sociobiology》1998,42(6):411-421
The goals of this study were to investigate the transmission and possible functions of chemical signals in intragroup communication
among ring-tailed lemurs, Lemur catta. In particular, I examined the effects of sex on these processes because sexual selection theory predicts specific functions
for chemical signals. I recorded all interactions with 214 scent marks of 11 male and 9 female ring-tailed lemurs during the
first 10 min following their deposition. I found that 62% of these scent marks were investigated with a median latency of
30 s and that 89% of investigated scents were also counter-marked by the receiver. The type of focal scent mark (male or female
anogenital and male antebrachial mark) had a significant effect on both the timing and type of response. Males investigated
and counter-marked female scents more often than vice versa, but significant second-order transitions suggested that the behavior
of an animal was not only influenced by the immediately preceding scent mark and that a scent is not completely masked by
a counter-mark. There was no evidence for an audience effect, and only social rank of female senders had an effect on receivers.
Variation in the response of receivers across reproductive seasons as a function of senders' sex indicated that female scents
may function in mate attraction and competition among females, whereas male scents may be primarily used in intrasexual competition.
Three main conclusions emerged. First, the exchange of olfactory signals within groups was highly structured and surprisingly
efficient. Second, olfactory signals may constitute general mesasages whose transfer is partly controlled by the receiver.
Finally, sexual selection theory provides a useful theoretical framework for functional examinations of mammalian olfactory
communication.
Received: 13 June 1997 / Accepted after revision: 20 March 1998 相似文献
333.
T. D. Seeley Susanne Kühnholz Anja Weidenmüller 《Behavioral ecology and sociobiology》1996,39(6):419-427
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
334.
Abstract: We evaluated the relative contributions of sampling error (randomly chosen standard errors applied as 0–30% of parameter estimates) in initial population size and vital rates (survival and reproduction) to the outcome of a simulated population viability analysis for grizzly bears ( Ursus arctos ). Error in initial population size accounted for the largest source of variation (model II analysis of variance, F 25,5 = 10.8, p = 0.00001) in simulation outcomes, explaining 60.5% of the variance. In contrast, error in vital rates contributed little to simulation outcomes ( F 25,5 = 0.61, p = 0.70), accounting for only 2.4% of model variation. Reduced global variation in vital rates, as a result of independent random sampling of annual deviates for each parameter, likely contributed to the results. Errors in estimates of initial population size, if ignored in PVA, have the potential to leave managers with estimates of population persistence that are of little value for making management decisions. 相似文献
335.
Abstract: The nonuse (or passive) value of nature is important but time‐consuming and costly to quantify with direct surveys. In the absence of estimates of these values, there will likely be less investment in conservation actions that generate substantial nonuse benefits, such as conservation of native species. To help overcome decisions about the allocation of conservation dollars that reflect the lack of estimates of nonuse values, these values can be estimated indirectly by environmental value transfer (EVT). EVT uses existing data or information from a study site such that the estimated monetary value of an environmental good is transferred to another location or policy site. A major challenge in the use of EVT is the uncertainty about the sign and size of the error (i.e., the percentage by which transferred value exceeds the actual value) that results from transferring direct estimates of nonuse values from a study to a policy site, the site where the value is transferred. An EVT is most useful if the decision‐making framework does not require highly accurate information and when the conservation decision is constrained by time and financial resources. To account for uncertainty in the decision‐making process, a decision heuristic that guides the decision process and illustrates the possible decision branches, can be followed. To account for the uncertainty associated with the transfer of values from one site to another, we developed a risk and simulation approach that uses Monte Carlo simulations to evaluate the net benefits of conservation investments and takes into account different possible distributions of transfer error. This method does not reduce transfer error, but it provides a way to account for the effect of transfer error in conservation decision making. Our risk and simulation approach and decision‐based framework on when to use EVT offer better‐informed decision making in conservation. 相似文献
336.
337.
The "tuned-error" hypothesis states that natural selection has tuned the divergence angle in the dances of the honey bee to
produce an optimal scatter of recruits across a resource. Weidenmüller and Seeley (Behav Ecol Sociobiol 46:190–199, 1999)
supported this hypothesis by finding smaller divergence angles in dances indicating potential home sites, which are always
point sources, than in dances indicating food sources, which often occur in patches. This study tested for the same effect,
but controlled for variables, e.g., substrate and context, that may have confounded those results. When performed on the same
substrate, divergence angle does not differ between dances for the two resources. Furthermore, dances performed for food within
an observation hive exhibit significantly greater divergence angle when performed on comb (as Weidenmüller and Seeley measured
food dances) than on hardware cloth (as they measured home-site dances on a swarm). These findings suggest that the angular
variance in direction indication in dances is more likely an artifact of physical constraints, rather than an adaptive modification
of a behavior that a bee could perform more precisely. 相似文献
338.
《Environmental Communication: A Journal of Nature and Culture》2013,7(4):423-440
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
339.
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
340.
核电厂主控室进行数字化变革后,操纵员执行状态评估任务的方式发生了巨大变化。为了有效地识别及评估数字化对状态评估的潜在影响,以知觉/循环、资源限制等认知理论为基础,以贝叶斯概率网络为工具,建立状态评估可靠度的影响因素模型。定性分析这些因素对状态评估任务的影响机制,并定量比较它们的影响程度。分析结果表明,界面管理任务和任务负荷变迁,对状态评估的影响最为显著。需采取针对性的措施,优先处理这些人因问题,以最大限度地提高数字化核电厂的安全水平。 相似文献