The attractiveness fragment—AFLP analysis of local adaptation and sexual selection in a caeliferan grasshopper, <Emphasis Type="Italic">Chorthippus biguttulus</Emphasis>

Genetic variability among males is a necessary precondition for the evolution of female choice based on indirect genetic benefits. In addition to mutations and host–parasite cycles, migration of locally adapted individuals offers an explanation for the maintenance of genetic variability. In a previous study, conducting a reciprocal transplant experiment on a grasshopper, Chorthippus biguttulus, we found that environmental conditions significantly influenced not only body condition but also an important trait of male calling song, the amplitude of song. Although not significant, all other analysed physical and courtship song traits and attractiveness were superior in native than in transferred males. Thus, we concluded that local adaptation has a slight but consistent influence on a range of traits in our study populations, including male acoustic attractiveness. In our present study, we scanned male grasshoppers from the same two populations for amplification fragment length polymorphism (AFLP) loci connected with acoustic attractiveness to conspecific females. We found greater differences in allele frequencies between the two populations, for some loci, than are expected from a balance between drift and gene flow. These loci are potentially connected with locally adapted traits. We examined whether these alleles show the proposed genotype environment interaction by having different associations with attractiveness in the two populations. One locus was significantly related to sexual attractiveness; however, this was independent of the males’ population affiliation. Future research on the evolution of female choice will benefit from knowledge of the underlying genetic architecture of male traits under intraspecific sexual selection, and the ‘population genomics’ approach can be a powerful tool for revealing this structure.     

On the defensive behavior of the grass snake <Emphasis Type="Italic">Natrix natrix</Emphasis> (Linnaeus, 1758)

Demonstrative imitations in the defensive behavior of grass snakes (Natrix natrix) captured in the Galich’ya Gora Reserve (70 ind.) and Kulikovskii Forestry (13 ind.), Lipetsk oblast, have been analyzed using statistical methods. The results suggest that grass snakes can play dead and imitate a venomous snake independently of their sex, age, and experience in receiving injuries. At the same time, there is evidence that such an ability is a hereditary trait subject to natural selection.     

煤矿瓦斯爆炸事故的应急救援物资调度模型研究

矿井瓦斯爆炸事故是煤矿安全生产中最严重的事故之一.为确保事故后应急救援的高效开展及减少应急物资调度过程中的经济损失,在以调度时间为第一的前提下,结合煤矿瓦斯爆炸事故实际,引入伤亡性和经济性两个优化目标,构建了一种在多出救点、多物资和多受灾点约束条件下的多目标应急物资调拨模型,并运用加权算法基本思想,确定了决策效用函数,同时结合瓦斯爆炸事故的时间紧迫度,在保证物资连续消耗的条件下,求解最优物资调度方案,并通过实例验证了可行性.     

印染废水反渗透深度处理的预处理工艺选择研究

在某大型印染企业生化出水的反渗透法深度处理中试试验中,分别采用三种预处理工艺:盘式过滤、板框压滤、(Flow-split(R)) SMF浸没式超滤.对反渗透系统的三种预处理工艺的运行情况、出水水质情况进行对比分析.分析结果表明,第一和第二种工艺的稳定性低,出水水质差,(Flow-split(R)) SMF系统能够去除大部分颗粒污染物,产水水质较好,产水流量较大,回收率高,大大减轻了RO膜的污染负荷,而且该工艺流程短、占地面积小、能耗低,作为RO系统的预处理工艺,具有较大优势.     

Predicting tree distributions in an East African biodiversity hotspot: model selection, data bias and envelope uncertainty

The Eastern Arc Mountains (EAMs) of Tanzania and Kenya support some of the most ancient tropical rainforest on Earth. The forests are a global priority for biodiversity conservation and provide vital resources to the Tanzanian population. Here, we make a first attempt to predict the spatial distribution of 40 EAM tree species, using generalised additive models, plot data and environmental predictor maps at sub 1 km resolution. The results of three modelling experiments are presented, investigating predictions obtained by (1) two different procedures for the stepwise selection of predictors, (2) down-weighting absence data, and (3) incorporating an autocovariate term to describe fine-scale spatial aggregation. In response to recent concerns regarding the extrapolation of model predictions beyond the restricted environmental range of training data, we also demonstrate a novel graphical tool for quantifying envelope uncertainty in restricted range niche-based models (envelope uncertainty maps). We find that even for species with very few documented occurrences useful estimates of distribution can be achieved. Initiating selection with a null model is found to be useful for explanatory purposes, while beginning with a full predictor set can over-fit the data. We show that a simple multimodel average of these two best-model predictions yields a superior compromise between generality and precision (parsimony). Down-weighting absences shifts the balance of errors in favour of higher sensitivity, reducing the number of serious mistakes (i.e., falsely predicted absences); however, response functions are more complex, exacerbating uncertainty in larger models. Spatial autocovariates help describe fine-scale patterns of occurrence and significantly improve explained deviance, though if important environmental constraints are omitted then model stability and explanatory power can be compromised. We conclude that the best modelling practice is contingent both on the intentions of the analyst (explanation or prediction) and on the quality of distribution data; generalised additive models have potential to provide valuable information for conservation in the EAMs, but methods must be carefully considered, particularly if occurrence data are scarce. Full results and details of all species models are supplied in an online Appendix.     

Resource defense polygyny shifts to female defense polygyny over the course of the reproductive season of a Neotropical harvestman

Although studies classify the polygynous mating system of a given species into female defense polygyny (FDP) or resource defense polygyny (RDP), the boundary between these two categories is often slight. Males of some species may even shift between these two types of polygyny in response to temporal variation in social and environmental conditions. Here, we examine the mating system of the Neotropical harvestman Acutisoma proximum and, in order to assess if mate acquisition in males corresponds to FDP or RDP, we tested four contrasting predictions derived from the mating system theory. At the beginning of the reproductive season, males fight with other males for the possession of territories on the vegetation where females will later oviposit, as expected in RDP. Females present a marked preference for specific host plant species, and males establish their territories in areas where these host plants are specially abundant, which is also expected in RDP. Later in the reproductive season, males reduce their patrolling activity and focus on defending individual females that are ovipositing inside their territories, as what occurs in FDP. This is the first described case of an arachnid that exhibits a shift in mating system over the reproductive season, revealing that we should be cautious when defining the mating system of a species based on few observations concentrated in a brief period. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Sperm removal and ejaculate size correlate with chelae asymmetry in a freshwater crayfish species

Asymmetry in traits of sexual relevance may impair copulation behaviour and sexual performance of males, ultimately resulting in a fitness cost. Freshwater crayfish males use chelae, a sexually selected trait, to secure and position the female prior to and during mating. Thus, a relatively large chelae asymmetry, resulting from accidental loss and regeneration of one cheliped after autotomy, could have great consequences for male sexual behaviour. We studied copulatory behaviour and sperm expenditure of males paired to a mated female in Austropotamobius italicus, a freshwater crayfish species where both male and female mate multiply and where last-mating males are able to actively remove previously deposited sperm. We aimed at assessing whether male sperm removal and expenditure varied according to sperm allocated by first-mating males, and according to copulation behaviour and phenotypic traits (carapace length, chelae length and relative chelae asymmetry) of second-mating males. Second-mating males did not adjust their ejaculate size in relation to first-mating male ejaculate, nor to the first-mating male’s sperm removed. Moreover, the amount of sperm removed by second-mating males increased with increasing first-mating males ejaculate size, and first-mating male sperm remaining after removal did not correlate with the original first-mating male ejaculate size. Interestingly, the amount of sperm removed by second-mating males decreased with increasing relative chelae asymmetry, while increasing with male body size. However, second-mating (but not first-mating) asymmetric-clawed males produced larger ejaculates than symmetric-clawed ones. Importantly, the proportion of second-mating male sperm remaining after the two matings did not vary with relative chelae asymmetry nor with body size of second-mating males. Thus, small, asymmetric-clawed crayfish males appear to adopt sperm allocation tactics that allow them to fully compensate for their inferior sperm removal ability.     

基于水文地貌分类的湿地干扰评价研究——以挠力河流域为例

基于湿地功能的水文地貌分类是一种评价湿地理化性质、生态功能及人类干扰的分类方法.借助ARCGIS软件的空间分析功能,采用层次分析法和模糊优选评价模型对挠力河流域湿地不同的水文地貌单元进行分类评价.结果显示,挠力河流域平原湿地生态区域可以划分为河岸带、低洼地、倾斜地和微高地4个水文地貌单元,人类干扰强度分别为0.043 2、0.093 0、0.397 6、0.937 4.其中河岸带和低洼地为轻干扰区,占湿地总面积50.09%;倾斜地为中度干扰区,占湿地总面积17.42%;微高地为严重干扰区,占湿地总面积32.49%.目前,湿地功能尚处于较好状态.     

Population differences in predation on Batesian mimics in allopatry with their model: selection against mimics is strongest when they are common

Batesian mimicry evolves when a palatable species, the “mimic,” resembles a dangerous species, the “model,” because both receive protection from predation. Yet, this protection should break down where the model is absent, because predators in such areas would not be under selection to avoid the model. Here, we test this prediction in a coral snake mimicry complex. We exposed plasticine replicas of milk snakes that closely mimic coral snakes to natural predators to determine if good mimetic milk snakes are preferentially attacked in allopatry with their model. Moreover, we evaluated whether attack rates on these replicas varied among three different allopatric regions that differed in the type of mimic found locally (i.e., good mimic, poor mimic, or no mimic). When all three regions were considered together, mimics were not preferentially attacked. When regions were analyzed separately, however, attacks on mimics were significantly greater than randomness only where good mimics were found. These variable levels of predation on good mimics might reflect frequency-dependent (i.e., apostatic) predation. In allopatric regions where good mimics are present, predators might have learned or evolved preferences for conspicuous, palatable prey that they encounter frequently. By contrast, in allopatric regions where good mimics are absent, predators might not have learned or evolved preferences for novel phenotypes. Thus, when predation is frequency-dependent, as long as good mimics are rare, they might not experience elevated levels of predation in allopatry with their model as predicted by the Batesian mimicry hypothesis.     

社会发展与环境资源冲突的典型案例——济南市生活垃圾填埋处置场选址问题研究

用冲突分析理论分析了社会发展与环境资源冲突的典型案例——济南市生活垃圾填埋处置场的选址问题,预测了这一冲突的发展,研究设计了解决这一冲突问题的处理方案．