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831.
The phenomenon of Batesian mimicry, where a palatable animal gains protection against predation by resembling an unpalatable model, has been a core interest of evolutionary biologists for 150 years. An extensive range of studies has focused on revealing mechanistic aspects of mimicry (shared education and generalization of predators) and the evolutionary dynamics of mimicry systems (co‐operation vs. conflict) and revealed that protective mimicry is widespread and is important for individual fitness. However, according to our knowledge, there are no case studies where mimicry theories have been applied to conservation of mimetic species. Theoretically, mimicry affects, for example, frequency dependency of predator avoidance learning and human induced mortality. We examined the case of the protected, endangered, nonvenomous smooth snake (Coronella austriaca) that mimics the nonprotected venomous adder (Vipera berus), both of which occur in the Åland archipelago, Finland. To quantify the added predation risk on smooth snakes caused by the rarity of vipers, we calculated risk estimates from experimental data. Resemblance of vipers enhances survival of smooth snakes against bird predation because many predators avoid touching venomous vipers. Mimetic resemblance is however disadvantageous against human predators, who kill venomous vipers and accidentally kill endangered, protected smooth snakes. We found that the effective population size of the adders in Åland is very low relative to its smooth snake mimic (28.93 and 41.35, respectively).Because Batesian mimicry is advantageous for the mimic only if model species exist in sufficiently high numbers, it is likely that the conservation program for smooth snakes will fail if adders continue to be destroyed. Understanding the population consequences of mimetic species may be crucial to the success of endangered species conservation. We suggest that when a Batesian mimic requires protection, conservation planners should not ignore the model species (or co‐mimic in Mullerian mimicry rings) even if it is not itself endangered. Implications of mimicry for Conservation of the endangered smooth snake  相似文献   
832.
Biogenic volatile organic compounds (BVOCs) play an important role in atmospheric chemistry and the carbon cycle. Isoprene is quantitatively the most important of the non-methane BVOCs (NMBVOCs), with an annual emission of about 400–600 TgC; about 90% of this is emitted by terrestrial plants. Incorporating a mechanistic treatment of isoprene emissions within land-surface schemes has recently become a focus for the modelling community, the aim being to quantify the potential magnitude of associated climate feedbacks. However, these efforts are hampered by major uncertainties about why plants emit isoprene and the relative importance of different environmental controls on isoprene emission. The availability and reliability of observations of isoprene fluxes from different types of vegetation is limited, and this also imposes constraints on model development. Nevertheless, progress is being made towards the development of mechanistic models of isoprene emission which, in conjunction with atmospheric chemistry models, will ultimately allow improved quantification of the feedbacks between the terrestrial biosphere and climate under past and future climate states.  相似文献   
833.
834.
We report data from a yearlong (2006–2007) study of black carbon concentrations ([BC]) measured at 5-min intervals with an Aethalometer in Karachi, Pakistan. Daily mean [BC] varied from about 1 to 15 μg m?3. However, short-term spikes exceeding 40 μg m?3 were common, occurring primarily during the morning and evening rush-hour periods. The [BC] values were highest during November through February, ~10 μg m?3, and lowest during June through September, ~2 μg m?3. Diurnal, seasonal, and day-of-the-week trends are discussed. It is demonstrated that these trends are strongly affected by meteorological patterns. A simple expression is applied to the concentration profiles to separate the effects of meteorological conditions and elucidate the underlying emissions patterns. Daily emissions varied from 14,000 to 22,000 kg of BC per day. When integrated over the year emissions for Karachi Proper were estimated at 6.7 kilometric tons per year and emissions for greater Karachi were 17.5 kilometric tons per year. Folding in the populations of each area yields BC emissions of 0.74 and 1.1 kg per person per year, respectively. Applying the model to previously collected data at Lahore, Pakistan yields emissions during November–January that are around a factor of two higher than those in Karachi, but because the BC measurements in Lahore covered only three months, no estimates of annual emissions were attempted. Given the large populations of these cities the local health impact from PM alone is expected to be severe but because of the high [BC] emissions the impact on the global climate may be equally significant.  相似文献   
835.
Abstract:  The Society for Conservation Biology (SCB) can enhance conservation of biodiversity in North America by increasing its engagement in public policy. Toward this end, the North America Section of SCB is establishing partnerships with other professional organizations in order to speak more powerfully to decision makers and taking other actions—such as increasing interaction with chapters—geared to engage members more substantively in science-policy issues. Additionally, the section is developing a North American Biodiversity Blueprint, which spans the continental United States and Canada and is informed by natural and social science. This blueprint is intended to clarify the policy challenges for protecting continental biodiversity, to foster bilateral collaboration to resolve common problems, and to suggest rational alternative policies and practices that are more likely than current practices to sustain North America's natural heritage. Conservation scientists and practitioners can play a key role by drawing policy makers' attention to ultimate, as well as proximate, causes of biodiversity decline and to the ecological and economic consequences of not addressing these threats.  相似文献   
836.
Environmental Science and Pollution Research - Traditional medicine (TM) also known as folk medicine consists of medical knowledge systems that were developed over generations in various countries...  相似文献   
837.
Environmental Science and Pollution Research - Reliable and accurate prediction model capturing the changes in solar radiation is essential in the power generation and renewable carbon-free energy...  相似文献   
838.
Environmental Science and Pollution Research - Trophic status in surface waters has been mostly monitored by measuring soluble reactive phosphorus (SRP) and total phosphorus (TP). Additional to...  相似文献   
839.
Environmental Science and Pollution Research - Cypermethrin (CYP) is a toxic manmade chemical compound belonging to pyrethroid insecticides contaminating the environment. Plantago major (PM) has...  相似文献   
840.
Environmental Science and Pollution Research - The Belt and Road Initiative (BRI) is closely linked to the ecological sustainability of the infrastructure ventures that intrinsically include the...  相似文献   
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