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151.
Glucocorticoids affect physiology and behaviour, reproduction and potentially sexual selection as well. Short-term and moderate glucocorticoid elevations are suggested to be adaptive, and prolonged and high elevations may be extremely harmful. This suggests that optimal reproductive strategies, and thus sexual selection, may be dose dependent. Here, we investigate effects of moderate and high elevations of blood corticosterone levels on intra- and intersexual behaviour and mating success of male common lizards Lacerta vivipara. Females showed less interest and more aggressive behaviour towards high corticosterone males and blood corticosterone levels affected male reproductive strategy. Males of moderate and high corticosterone elevations, compared with Control males, showed increased interest (i.e., higher number of chases, tongue extrusions, and approaches) towards females and high corticosterone males initiated more copulation attempts. However, neither increased male interest nor increased copulation attempts resulted in more copulations. This provides evidence for a best-of-a-bad-job strategy, where males with higher corticosterone levels compensated for reduced female interest and increased aggressive female behaviour directed towards them, by showing higher interest and by conducting more copulation attempts. Blood corticosterone levels affected intrasexual selection as well since moderate corticosterone levels positively affected male dominance, but dominance did not affect mating success. These findings underline the importance of female mate choice and are in line with adaptive compensatory behaviours of males. They further show that glucocorticoid effects on behaviour are dose dependent and that they have important implications for sexual selection and social interactions, and might potentially affect Darwinian fitness.  相似文献   
152.
The red-belly toads (Melanophryniscus) of southern South America secrete defensive alkaloids from dermal granular glands. To date, all information on Melanophryniscus alkaloids has been obtained by extraction from either skins or whole organisms; however, in other amphibians, tetrodotoxins, samandarines, and bufadienolides have been detected in both skin and other organs, which raise the possibility that lipophilic alkaloids may occur in non-integumentary tissues in Melanophryniscus as well. To test this hypothesis, we studied the distribution of alkaloids in the skin, skeletal muscle, liver, and mature oocytes of the red-belly toad M. simplex from three localities in southern Brazil. Gas chromatography and mass spectrometry of skin extracts from 11 individuals of M. simplex resulted in the detection of 47 alkaloids (including isomers), 9 unclassified and 38 from 12 known structural classes. Each alkaloid that was present in the skin of an individual was also present in the same relative proportion in that individual??s skeletal muscle, liver, and oocytes. The most abundant and widely distributed alkaloids were the pumiliotoxins 251D, 267C, and 323A, 5,8-disubstituted indolizidines 207A and 223D, 5,6,8-trisubstituted indolizidine 231B, 3,5-disubstituted pyrrolizidines cis-223B and cis- and trans-251K, and izidine 211C. We report the first record of piperidines in Melanophryniscus, bringing the total number of alkaloid classes detected in this genus to 16. Alkaloid composition differed significantly among the three study sites. The functional significance of defensive chemicals in non-integumentary tissues is unknown.  相似文献   
153.
Tourists are particularly vulnerable when natural disasters occur in regions that they are visiting. It is assumed that they lack awareness and understanding of the actions that they need to take in such circumstances. This study examines the responses of tourists in times of disaster, building on empirical data collected through large‐scale surveys conducted in Bali and Yogyakarta, Indonesia, in 2015. Both are important tourist destinations in the country that have suffered major disasters in recent years. The different types of responses to these events are framed using a grid/group analysis stemming from cultural theory. The study resulted in three key findings: (i) current disaster management planning largely follows a single rationale; (ii) tourists are not a homogeneous group, but rather a complex, diverse, and dynamic body of stakeholders; and (iii) the focus of disaster management planning should shift from a single rationale to a polyrational methodology. Disaster managers need to consider, therefore, these different aspects in the context of preparedness.  相似文献   
154.
Social dominance is a fundamental aspect of male evolutionary ecology in polygynous mammals because it determines access to estrous females. As it is rarely possible to monitor marked individuals of known morphology, little is known about the determinants of male dominance. We studied the social structure of Alpine ibex males in Gran Paradiso National Park, Italy in 2003, 2006, and 2007. Dominance interactions produced a linear social hierarchy. In ibex males, body mass and horn length are key traits in male-male combat, and both increase with age. We explored the links between age, body mass, horn length, and social rank. Ibex males showed much age-independent phenotypic heterogeneity and rapidly growing males reached high rank at a younger age than slow-growing males. Because there is no trade-off between horn growth and longevity, fast-growing males may face weak potential costs of rapid growth and high fitness benefit of achieving high rank. Violent interactions were more likely to occur between males similar in both mass and horn length, independently of age. We suggest that only high-quality individuals can afford a strategy of rapid growth for both secondary sexual characters, and likely reap substantial fitness benefits.  相似文献   
155.
The present paper provides a conceptual and empirical examination regarding the relevance of the construct curiosity for work‐related outcomes. On the basis of a review and integration of the literature regarding the construct itself, the construct is conceptually linked with performance in the work context. In line with a confirmatory research strategy, the sample of the present study (N = 320) has requirements which reflect this conceptual link. Results from a concurrent validation study confirmed the hypothesis regarding the significance of curiosity for job performance (r = .34). Furthermore, incremental validity of curiosity above 12 cognitive and non‐cognitive predictors for job performance suggests that curiosity captures variance in the criterion that is not explained by predictors traditionally used in organizational psychology. It is concluded that curiosity is an important variable for the prediction and explanation of work‐related behavior. Furthermore, given the dramatic changes in the world of work, the importance is likely to rise, rather than to decline, which has important implications for organizational theories and applied purposes, such as personnel selection. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
156.
ABSTRACT

Across the Global South, community-based adaptation (CBA) projects are increasingly being implemented in an effort to respond effectively and sustainably to the impacts of climate change, with a particular focus on people’s livelihoods. Despite an increase in the number of CBA projects being implemented, detailed analysis and evaluation of their efficacy and the barriers faced in achieving successful outcomes is lacking. This study draws on an analysis of grey literature (i.e. project and donor reports) to explore the barriers faced in achieving effective CBA. An extensive global search of online project evaluations yielded 25 documents comprising 69 projects from which this analysis is based. This paper first presents an overview of the 69 projects and highlights any trends. Second, this paper describes the barriers to CBA according to three broad themes: socio-political, resource, and physical systems and processes. Following this is a discussion of the most prevalent barriers: cognitive and behavioural, financial, and human resources. Third, this paper discusses the key findings elucidated from this review. This includes the need for greater sharing of project reports and findings so lessons can be learned across spatial and temporal scales, and the disparity between critical academic literature on CBA and what is implemented in practice.  相似文献   
157.
Abstract

This paper examines the role and effectiveness of local institutions in the management of forest biodiversity in New Dabaga-Ulongambi Forest Reserve, Tanzania. Data were obtained through questionnaires, interviews, focus group discussions, participatory rural appraisal and field observations. The study revealed that the most remarkable local institutions connected to forest biodiversity management include: Village Natural Resources Management Committee (92%), tree nursery group (79.4%), beekeeping groups (61.1%), fish farming (43.3%), livestock rearing group (33.9%). Main activities carried out by local institutions which directly contribute to the sustainability of forest reserve include: forest patrols, fire extinguish, preparation of fire breaks, planting of trees along the forest boundaries, creation of awareness, arresting of forest defaulters, participation in income generation activities. For the purpose of realization that local communities are capable of managing forest biodiversity through their traditional institutions, the policy should provide tangible opportunity for local communities to meet their needs as they manage the forests.  相似文献   
158.
Abstract

To determine the climate changes that are due to natural variability and those due to human activities is quite challenging, just like delineating the impacts. Moreover, it is equally difficult to ascertain the adaptive strategies for coping with the climate changes and in particular for developing countries like Kenya. While climate change is a global phenomenon, the impacts are more or less specific to local areas such as observed in Kenyan case. Therefore climate change impacts adaptation strategies are appropriately applicable to a given local perspective. The study investigated the main indicators of climate change and effective adaptive strategies that can be employed in Kenya. Based on online questionnaire survey, the study established unpredictable rainfall patterns as the major indicator of climate change in the country, while water harvesting and change of cropping methods are the best adaptive strategies.  相似文献   
159.
Efforts by many governments to mitigate climate change by increasing deployment of renewable energy technologies have raised the importance of issues of public acceptance. The ‘NIMBY’ (Not In My Backyard) concept, although popular, has been critiqued as an appropriate and valid way to explain local opposition. This study applies an alternative approach, empirically investigating the role of place attachment and place-related symbolic meanings in explaining public responses to a tidal energy converter in Northern Ireland, said to be the first grid-connected device of its kind in the world. 271 residents in two nearby villages completed questionnaire surveys, three months post-installation, following up preliminary qualitative research using focus groups. Although results indicated predominantly positive and supportive responses to the project, manifest by emotional responses and levels of acceptance, significant differences between residents in each village were also observed. Contrasting patterns of association between place attachment and emotional responses suggest that the project enhanced rather than disrupted place attachments only in one of the two villages. In regression analyses, place attachment emerged as a significant, positive predictor of project acceptance in both places, affirming its value in explaining public response. Place-related symbolic meanings also emerged as significant, with contrasting sets of meanings proving significant in each context. Implications of the findings for research on place attachment and responses to land-use changes, as well as for developers seeking to engage with residents affected by energy projects are discussed.  相似文献   
160.
Environmental Management System (EMS) has been one of the important tools for sustainable construction for around two decades. However, many issues concerning sustainable development have not been properly addressed, and there is a need for the introduction of green specifications to advance green performance in construction through contract management. This paper defines green specifications, identifies the reasons for adopting green specifications and highlights the environmental issues that may not be addressed by solely adopting EMS. It also presents the results of a recent survey of practitioners concerning their opinions towards green specifications and possible impacts arising from their adoption. From the results of the survey, a framework for developing green specifications is deemed valuable for the cities striving for sustainability. Interestingly, the level of acceptable changes brought about by green specifications as perceived by different industry stakeholders is found to be unrelated to whether they were from organizations implementing EMS or not.  相似文献   
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