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This introduction article is for the special issue ‘Managing organizations for sustainable development in emerging countries: natural resources, biodiversity, and climate change’ in the International Journal of Sustainable Development & World Ecology and presents an introduction to the topics and summarizes accepted contributions in the special issue. The accepted works may contribute with organizational management in the search for more sustainable organizations. The works focus on the challenges of managing organizations in a context of degradation of natural resources, loss of biodiversity, and climate change. Accepted papers discuss these issues, based on the reality of emerging economies (e.g. Brazil, India, and China).  相似文献   

3.
Complex signal function: developing a framework of testable hypotheses   总被引:1,自引:1,他引:1  
The basic building blocks of communication are signals, assembled in various sequences and combinations, and used in virtually all inter- and intra-specific interactions. While signal evolution has long been a focus of study, there has been a recent resurgence of interest and research in the complexity of animal displays. Much past research on signal evolution has focused on sensory specialists, or on single signals in isolation, but many animal displays involve complex signaling, or the combination of more than one signal or related component, often serially and overlapping, frequently across multiple sensory modalities. Here, we build a framework of functional hypotheses of complex signal evolution based on content-driven (ultimate) and efficacy-driven (proximate) selection pressures (sensu Guilford and Dawkins 1991). We point out key predictions for various hypotheses and discuss different approaches to uncovering complex signal function. We also differentiate a category of hypotheses based on inter-signal interactions. Throughout our review, we hope to make three points: (1) a complex signal is a functional unit upon which selection can act, (2) both content and efficacy-driven selection pressures must be considered when studying the evolution of complex signaling, and (3) individual signals or components do not necessarily contribute to complex signal function independently, but may interact in a functional way.Communicated by A. Cockburn  相似文献   

4.
Noise that masks communication signals can affect the evolution of signal form and decisions about when and where to communicate. For the many invertebrates that communicate using plant-borne vibrations, wind is considered to be the major source of environmental noise. However, the influence of wind-induced vibrations on signaling behavior has not been experimentally tested. We tested the hypothesis that wind-induced noise influences signaling behavior in a plant-feeding insect (the treehopper, Enchenopa binotataPtelea’) in which mating is preceded by a vibrational duet between females and mate-searching males. We first characterized the diel signaling patterns of males in the field to identify the wind conditions under which signaling typically takes place. We then experimentally tested two predictions of the hypothesis: (1) that males use gap detection to initiate signaling during relatively wind-free periods; and (2) that females respond less to signals given in the presence of wind-induced vibrations. Both predictions were met, indicating that wind-induced noise is an important influence on the behavior of insects that use plant-borne vibrations.  相似文献   

5.
Cover Caption     
Cover : Tropical biodiversity faces an array of threats, including habitat destruction, climate change, and overhunting. In this issue, a special section provides new insights into the tropical biodiversity crisis. Fundamental drivers of deforestation are changing, which has important implications for conservation strategies. Emerging threats, such as climate change, overhunting, wildfires, and exotic pathogens, could increasingly operate in synergism with habitat loss and degradation. Photo credits: rainforest possum, Mike Trenerry; smokestacks, © http://www.fotosearch.com ; bulldozer in Indonesia and sunset in India, William Laurance; chameleon in Gabon, Carlton Ward; elephant skeleton in Gabon, Ralph Buij. See pages 1382–1457.  相似文献   

6.
Modeling the carbon cycle of urban systems   总被引:2,自引:0,他引:2  
Although more than 80% of carbon dioxide emissions originate in urban areas, the role of human settlements in the biosphere evolution and in global carbon cycling remains largely neglected. Understanding the relationships between the form and pattern of urban development and the carbon cycle is however crucial for estimating future trajectories of greenhouse gas concentrations in the atmosphere and can facilitate mitigation of climate change. In this paper I review state-of-the-art in modeling of urban carbon cycle. I start with the properties of urban ecosystems from the ecosystem theory point of view. Then I discuss key elements of an urban system and to which degree they are represented in the existing models. In conclusions I highlight necessity of including biophysical as well as human related carbon fluxes in an urban carbon cycle model and necessity of collecting relevant data.  相似文献   

7.
Scientific consensus shows that the changes related to climate change are already occurring and will intensify in the future. This will likely result in significant alterations to coastal ecosystems such as mangroves, increase coastal hazards and affect lifestyles of coastal communities. There is increasing speculation that mangrove, a socio-economically important ecosystem, will become more fragile and sensitive to uncertain climate variability such as sea level rise. As a result, mangrove-dependent societies may find themselves trapped in a downward spiral of ecological degradation in terms of their livelihoods and life security. Strengthening the resilience capacity of coastal communities to help them cope with this additional threat from climate change and to ensure sustainability calls for immediate action. In this context, this paper critically examines the regional implications of expected sea level rise and threats to mangrove-dependent communities through a case study approach. The main objective is to highlight the requirement for climate change communication and education to impart information that will fulfil three expectations: (1) confer understanding; (2) assess local inference on climate change through a participatory approach; and (3) construct a framework for climate change awareness among mangrove-dependent communities through community-based non-formal climate change education. This scale of approach is attracting increasing attention from policymakers to achieve climate change adaptation and derive policies from a social perspective.  相似文献   

8.
In lekking species, the allocation of effort into mate attraction signals is not uniform over time, and signalers may expend the greatest effort when potential mates are nearby. Close-range courtship interactions are critical determinants of male fitness and the study of these interactions can therefore answer important questions in sexual selection. In anurans, attention has largely focused on long-range mate attraction mediated by acoustic signaling. However, many species also engage in courtship behaviors at close range, and the cues that elicit these behaviors are unknown but likely to be non-acoustic. I performed an experiment in which I assessed the role of female visual cues in eliciting courtship calls by males of the nocturnal treefrog Hyla versicolor. Males that could see an approaching female were more likely to give courtship calls than those that could not. These results provide some of the first evidence for an effect of vision on calling behavior in a nocturnal anuran and demonstrate that multiple sensory modalities are involved in the final stages of mate attraction.  相似文献   

9.
Abstract:  Several studies have reported climate-associated changes in phenotypically plastic traits of amphibians, yet it remains unknown whether amphibians can manifest an evolutionary response to global climate change at the rate and magnitude that it is occurring. To assess this issue, we examined temporal change in the morphology of the red-backed salamander ( Plethodon cinereus ), a small, abundant woodland salamander distributed widely in eastern North America with two distinct morphotypes: striped individuals associated with cooler microclimates and unstriped individuals associated with warmer microclimates. We compiled morph frequencies for 50,960 individual salamanders from 558 sites as recorded in the published literature and in unpublished field notes of herpetologists between 1908 and 2004. We observed that striping probability increased with increasing latitude, longitude, and elevation and decreased (from 80% to 74% range wide) with time. The combined forces of regional climate warming and, particularly, forest disturbance have evidently been sufficient to cause morphological evolution in this amphibian over the last century.  相似文献   

10.
Mate choice often takes place in group settings, such as leks or choruses, in which numerous individuals display and compete for mates simultaneously. In addition to well-known preferences for male traits like size and signaling rate, females of group-displaying species often show preferences that are based on the relative timing of male signals, generally preferring the leading signal. Variation in male signal timing behavior may therefore affect male attractiveness and, ultimately, reproductive success. I used acoustic communication in green treefrogs (Hyla cinerea) to assess the amount of signal timing variation found in natural choruses and to test hypotheses about the sources of variation in signal timing behavior. I recorded dyads of vocally interacting males in the field to describe patterns of variation in signal timing behavior. Incorporating information about female signal timing preferences, I also assessed the amount of variation in signal timing that is likely to be selectively neutral, as well as the amount that is likely under selection by female choice because it involves attractive or unattractive signal placement. I show that there is considerable variation in signal timing behavior, particularly involving neutral signal timing placement. I also show that between-male variation in other traits (size, signal period) is partly linked to variation in signal timing behavior and discuss these findings in terms of male attractiveness and sexual selection in group-displaying organisms.  相似文献   

11.
We integrate new challenges to thinking about resource markets and sustainable resource use policies in a general framework. The challenges, emerging from six papers that JEEM publishes in a special issue, are (i) demand uncertainty and stockpiling, (ii) international trade and resource dependence, (iii) deforestation, and (iv) intertemporal effects of climate change policies (“Green Paradox”). We discuss new insights and results on these issues by fitting them into the Hotelling model of non-renewable resource depletion.  相似文献   

12.
Studies increasingly explore whether there is variation between individuals in how they adjust their behavior to different environmental contexts using random regression analysis (RR). RR estimates the between-individual variance in elevation (expected behavior in the mean environment) and variance in plasticity (individual-specific adjustment of behavior to the environment) and the covariance between these properties. These (co)variances allow deriving both environment-specific repeatability estimates and the individual-level correlation in behavior between environmental conditions, both of which are of key interest for understanding consistency in behavior over space and time, a core issue in animal personality research. However, very few studies use the RR estimates to produce this information. In this paper, I outline how to extract this information (including example code in R) and apply the approach to 16 estimates based on nine published RR studies. Despite the fact that the behaviors have a decent repeatability under different environmental conditions, I find that in half the cases, the cross-environmental correlation is low (<0.4). This implies that individuals differ in their behavioral trait values but that the ranking of these individual values tends to change between environmental conditions. This level of inconsistency in animal personality traits appears not to have been fully appreciated, and future studies on plasticity using RR should explicitly include it.  相似文献   

13.
Predation is an important cost of communication in animals and thus a potent selection pressure on the evolution of signaling behavior. Heterospecific eavesdropping by predators may increase the vulnerability of vocalizing prey, particularly during low light, such as at dusk when nocturnal predators are actively hunting. Despite the risk it entails, dawn and dusk chorusing is common in passerines. However, the dusk chorus has not been studied much, neglecting the opportunity for understanding how eavesdropping between predators and prey may shape communication in birds. Here, we report the first demonstration of simulated predation risk (playback of owl vocalizations) altering the dusk chorus of a diurnal passerine, the veery (Catharus fuscescens). Veeries have a pronounced dusk chorus, singing well after sunset and potentially exposing themselves to predation by owls. In response to brief playbacks of owl calls (~30 s of calls presented three times over 25 min), veeries sang fewer songs post-sunset and stopped singing earlier relative to control trials. These changes in singing remained evident 30 min after the last owl stimulus. Although the avian dusk chorus has received relatively little attention to date, our results suggest that the dusk chorus may pose a higher predation risk to singing males that may influence the evolution of singing behavior in diurnal birds.  相似文献   

14.
We integrate new challenges to thinking about resource markets and sustainable resource use policies in a general framework. The challenges, emerging from six papers that JEEM publishes in a special issue, are (i) demand uncertainty and stockpiling, (ii) international trade and resource dependence, (iii) deforestation, and (iv) intertemporal effects of climate change policies (“Green Paradox”). We discuss new insights and results on these issues by fitting them into the Hotelling model of non-renewable resource depletion.  相似文献   

15.
This paper estimates the impact of climate change on the prevalence of criminal activity in the United States. The analysis is based on a 30-year panel of monthly crime and weather data for 2997 US counties. I identify the effect of weather on monthly crime by using a semi-parametric bin estimator and controlling for state-by-month and county-by-year fixed effects. The results show that temperature has a strong positive effect on criminal behavior, with little evidence of lagged impacts. Between 2010 and 2099, climate change will cause an additional 22,000 murders, 180,000 cases of rape, 1.2 million aggravated assaults, 2.3 million simple assaults, 260,000 robberies, 1.3 million burglaries, 2.2 million cases of larceny, and 580,000 cases of vehicle theft in the United States.  相似文献   

16.
Grassland is one of the most widespread vegetation types worldwide and plays a significant role in global carbon cycling. Understanding the sensitivity of grassland to climate change and the effect of climate changes on the grassland ecosystems is a key issue in global carbon cycling. One of the goals of this study was to evaluate the three net primary productivity (NPP)–climate models, i.e. the Miami model, the Schuur model and the classification indices-based model. Results indicated that the classification indices-based model was the most effective model at estimating large-scale grassland NPP. In this research, changes in the spatial pattern of global potential grassland from recent past (1950–2000) to future (2001–2050) A2a scenario were analysed with the integrated orderly classification system of grassland (IOCSG) approach in a Geographic Information System (GIS) environment. NPP was evaluated with the classification indices-based model. Results indicate that under recent past climatic conditions, the main parts of global grassland are the savanna and tundra and alpine grassland and will be converted into the savanna, steppe and semi-desert grassland in A2a scenario. As a whole, areas of grassland will increase by 31.76 million hectares. The classification indices-based model estimated a 12.40% increase of total NPP in grassland from recent past to A2a scenario. It will impose a new issue for future grassland researches to support sustainable development and to provide action relevant knowledge to meet the challenge of climate change.  相似文献   

17.
Begging behavior and food acquisition by brown-headed cowbird nestlings   总被引:5,自引:0,他引:5  
Understanding the selective forces that limit the exaggeration of begging signals is a critical issue in understanding the evolution of begging behavior. I studied the begging behavior of nestlings of the brown-headed cowbird (Molothrus ater), a brood parasite. In the nests of indigo buntings (Passerina cyanea), brown-headed cowbird nestlings received approximately twice as much food per hour than their host nestmates. I tested three hypotheses for the mechanism by which cowbirds acquired more food than their bunting nestmates: the size advantage hypothesis, the signal exaggeration hypothesis, and the novel begging behavior hypothesis. I found support for the hypotheses that cowbirds acquire more food as a result of their larger body size, and due to the exaggeration of begging signals that are not dependent on body size. I did not find support for the role of novel begging behaviors in cowbird food acquisition. These results suggest that food acquisition by host chicks in unparasitized nests could be increased by the exaggeration of begging signals. Recent work suggests that such exaggeration may be limited by the risk of nest predation, but further studies are needed. Received: 12 December 1997 / Accepted after revision: 29 December 1997  相似文献   

18.
Sensory traps are signal mimics that elicit out-of-context behaviors by exploiting the adaptive, neural responses of signal receivers. Sensory traps have long been invoked in studies of mate and prey attraction, but the possible roles of sensory traps in mutualisms (cooperation between species) have yet to be thoroughly examined. Our review identifies four candidate roles for sensory traps in the evolution of mutualistic interactions: reassembly, error reduction, enforcement, and cost reduction. A key consequence of sensory traps is that they limit the applicability of partner choice and biological market models of mutualism. We conclude by suggesting that an important research topic in the evolution of cooperation should be to identify any mechanisms that increase the truthfulness of communication between cooperating species.  相似文献   

19.
There is a general lack of knowledge as regards the effects of climate change on pollutant behavior. This is particularly true of the Asia-Pacific Region (APR). This region has major significance in terms of global pollutant emission and also displays a wide variety of environments. This review presents the authors’ opinions on possible implications of climate change for pollutant behavior in the APR. Although differing responses can be expected across the region, there are clear implications as regards the short- and long-term behavior of pollutants. Effects can be predicted through modeling, but further data are required for model calibration. Nevertheless, it can be predicted that climate change will affect processes including global distillation of persistent organic pollutants, airborne transport of heavy metals, half-life of readily degradable pollutants, and eutrophication in water bodies. Particulates are expected to play a central role in mediating the effects of climate change, and successful predictive models will need to be based on particulate-mediated transport and behavior. Climate change also has the potential to cause an increase in the intensity and frequency of harmful algal blooms in aquatic environments throughout the region, with significant implications for supply of both food and drinking water.  相似文献   

20.
Abstract: The need to adapt to climate change has become increasingly apparent, and many believe the practice of biodiversity conservation will need to alter to face this challenge. Conservation organizations are eager to determine how they should adapt their practices to climate change. This involves asking the fundamental question of what adaptation to climate change means. Most studies on climate change and conservation, if they consider adaptation at all, assume it is equivalent to the ability of species to adapt naturally to climate change as stated in Article 2 of the United Nations Framework Convention on Climate Change. Adaptation, however, can refer to an array of activities that range from natural adaptation, at one end of the spectrum, to sustainability science in coupled human and natural systems at the other. Most conservation organizations deal with complex systems in which adaptation to climate change involves making decisions on priorities for biodiversity conservation in the face of dynamic risks and involving the public in these decisions. Discursive methods such as analytic deliberation are useful for integrating scientific knowledge with public perceptions and values, particularly when large uncertainties and risks are involved. The use of scenarios in conservation planning is a useful way to build shared understanding at the science–policy interface. Similarly, boundary organizations—organizations or institutions that bridge different scales or mediate the relationship between science and policy—could prove useful for managing the transdisciplinary nature of adaptation to climate change, providing communication and brokerage services and helping to build adaptive capacity. The fact that some nongovernmental organizations (NGOs) are active across the areas of science, policy, and practice makes them well placed to fulfill this role in integrated assessments of biodiversity conservation and adaptation to climate change.  相似文献   

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