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41.
The Mediterranean deep-water kelp Laminaria rodriguezii is an endangered species in the Adriatic Sea
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Behaviors that appear to be plastic may well be determined by environmental influences during development. Being able to produce a wide range of variants of one kind of behavior, e.g., a very short and a very long response time to a stimulus under different environmental conditions, can be described as behavioral plasticity. How such behavioral reaction norms develop for individuals is poorly understood, but several factors are likely to play a role. We investigated what factors may affect how the risk-taking behavior of the lesser wax moth, Achroia grisella, is shaped during ontogeny. We manipulated larval density to represent the potential intensity of future competition for females in a lek of males, determined adult moths’ reaction to predator signals, and tested for plasticity in the silence response, i.e., the acoustic evasion behavior of the moths during the experiments. While we found no effect of larval density on either the probability or the duration of the silence response, 11 % of the variance in duration could be explained by differences between families, and 30 % of the variance was the result of differences between individuals. We found evidence for habituation to the predator signal, clearly indicating that the silence response is a plastic-enough trait to be adjustable to the immediate environment. These results suggest that the degree to which individuals take risks in the context of acoustic signaling depends more on the immediate context and, possibly, genetic differentiation than it is a product of adaptive developmental plasticity. 相似文献
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The morphology of the variously coloured scoli (bristle-bearing structures on the integument, producing an exocrine secretion) on caterpillars of Hyalophora cecropia and the secondary chemistry of the discharged secretions have been investigated for the first time and compared. According to our scanning electron microscopic study, the red/orange, yellow and blue coloured groups of these glands differ morphologically. Gas chromatographic-mass spectrometric analyses showed that the patterns of secondary compounds in the respective glandular secretions are also different. Furthermore, the secretion of the penultimate larval instar is chemically distinct from that of the last instar, as are both secretions from the respective haemolymph. The results favour the idea that the differences in scoli colour, morphology and chemistry could affect various predator species differently.Electronic Supplementary Material Supplementary material is available for this article if you access the article at . A link in the frame on the left on that page takes you directly to the supplementary material. 相似文献
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In their seminal model of work–family enrichment, Greenhaus and Powell (2006) theorized five categories of work resources to have an impact on work–family enrichment. Using a matched set of 351 dual‐career spouses, we explored how these unique work resources contribute to work–family enrichment and how they spill over to shape job incumbents' family outcomes and cross over to spouse outcomes. Results support indirect effects for the work resources of developmental experiences, supervisor support, schedule control, and self‐efficacy, but not salary, on marital satisfaction and family functioning through the job incumbent's work–family enrichment. In addition, we found support for the crossover of these indirect effects to the spouse through the spouse's positive crossover transmission, which facilitated the spouse's marital satisfaction and commitment to the job incumbent's organization. Our results suggest that multiple work resources have an impact on work–family enrichment and that the flow of positive work resources through work–family enrichment spills over to impact outcomes for the job incumbent and crosses over to the spouse. 相似文献
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Studying citizen science through adaptive management and learning feedbacks as mechanisms for improving conservation 下载免费PDF全文
Rebecca Jordan Steven Gray Amanda Sorensen Greg Newman David Mellor Greg Newman Cindy Hmelo‐Silver Shannon LaDeau Dawn Biehler Alycia Crall 《Conservation biology》2016,30(3):487-495
Citizen science has generated a growing interest among scientists and community groups, and citizen science programs have been created specifically for conservation. We examined collaborative science, a highly interactive form of citizen science, which we developed within a theoretically informed framework. In this essay, we focused on 2 aspects of our framework: social learning and adaptive management. Social learning, in contrast to individual‐based learning, stresses collaborative and generative insight making and is well‐suited for adaptive management. Adaptive‐management integrates feedback loops that are informed by what is learned and is guided by iterative decision making. Participants engaged in citizen science are able to add to what they are learning through primary data collection, which can result in the real‐time information that is often necessary for conservation. Our work is particularly timely because research publications consistently report a lack of established frameworks and evaluation plans to address the extent of conservation outcomes in citizen science. To illustrate how our framework supports conservation through citizen science, we examined how 2 programs enacted our collaborative science framework. Further, we inspected preliminary conservation outcomes of our case‐study programs. These programs, despite their recent implementation, are demonstrating promise with regard to positive conservation outcomes. To date, they are independently earning funds to support research, earning buy‐in from local partners to engage in experimentation, and, in the absence of leading scientists, are collecting data to test ideas. We argue that this success is due to citizen scientists being organized around local issues and engaging in iterative, collaborative, and adaptive learning. 相似文献
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K. Reinhold 《Behavioral ecology and sociobiology》1996,39(3):189-194
Offspring sex ratio at hatching was examined in the bushcricket Poecilimon veluchianus. Offspring sex ratios varied significantly between females (Fig. 1). Low mortality prior to sex determination established
that this heterogeneity was already present in the primary offspring sex ratio. Sperm age and female age had no influence
on offspring sex ratio (Fig. 2). Male age at copulation, however, correlated significantly with offspring sex ratio (Fig. 3).
There were two types of males: one type produced predominantly daughters when young and an increasing proportion of sons with
age. The other type produced, independent of age, 1:1 offspring sex ratios (Fig. 4). The two types of males seem to occur
in approximately equal numbers. Sex ratio variation (1) may adaptively compensate for local sex ratio biases caused by sex-specific
motility, or (2) it may be adaptive if there is a sex-differential effect of laying date on offspring fitness.
Received: 14 March 1996/Accepted after revision: 24 June 1996 相似文献