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1.
Abstract: Management and conservation of large carnivores increasingly includes conflicts with humans. Consequently, a greater understanding of spatiotemporal trends of conflicts is needed to efficiently allocate resources and apply targeted management. Therefore, we examined spatial and temporal distribution of American black bear (Ursus americanus; hereafter, bear)-human conflicts in Colorado, USA, related to 3 conflict types (agriculture operations, human development, and road kills). We used the Getis-Ord Gi* spatial clustering statistic to describe location and assess magnitude of bear-human conflicts in Colorado during 1986–2003 and investigated temporal trends of bear-human conflicts by type. Bear-human conflicts showed distinct spatial clustering by type, and areas of high clustering overlapped conflict types. Clustering for agriculture operations conflicts had the largest overall Gi* value and overlapped counties with high sheep production. Both human development and road-kill conflict clusters were high in areas of high-quality oak (Quercus spp.)—shrub habitat in the central and southern portions of Colorado's Front Range region and near the city of Durango in southwestern Colorado. Bear-human conflicts varied by year and type but overall increased during the 18 years. Summed across years, most conflicts were related to agriculture (32%), followed by road kills (27%) and human development (24%). The greatest proportion of agriculture operations-related conflicts (76%), human development-related conflicts (36%), and road kills (47%) occurred in 1988, 1999, and 2003, respectively. Considering that bear-human conflicts in Colorado increased over time and will likely continue to increase, we suggest wildlife managers improve data collection by obtaining detailed location data, categorizing conflict types uniformly, and applying conflict regulations consistently to strengthen inference of similar analyses. We also suggest that managers target efforts to mitigate damage by focusing on areas with high clustering of conflicts.  相似文献   

2.
Nucleocytoplasmic transport is a broadly conserved process across eukaryotes. Despite its essential function and conserved mechanism, components of the nuclear transport apparatus have been implicated in genetic conflicts in Drosophila, especially in the male germ line. The best understood case is represented by a truncated RanGAP gene duplication that is part of the segregation distorter system in Drosophila melanogaster. Consistent with the hypothesis that the nuclear transport pathway is at the heart of mediating genetic conflicts, both nucleoporins and directionality imposing components of nuclear transport have previously been shown to evolve under positive selection. Here, we present a comprehensive phylogenomic analysis of importins (karyopherins) in Drosophila evolution. Importins are adaptor molecules that physically mediate the transport of cargo molecules and comprise the third component of the nuclear transport apparatus. We find that importins have been repeatedly gained and lost throughout various stages of Drosophila evolution, including two intriguing examples of an apparently coincident loss and gain of nonorthologous and noncanonical importin-α. Although there are a few signatures of episodic positive selection, genetic innovation in importin evolution is more evident in patterns of recurrent gene birth and loss specifically for function in Drosophila testes, which is consistent with their role in supporting host genomes defense against segregation distortion.  相似文献   

3.
The genetic toxicity of atrazine, a member of the s-triazine herbicides, was reviewed with the objective of classifying the chemical. Atrazine has been subjected to a broad range of genetic tests with predominantly negative results. Some publications, specifically those measuring dominant lethality in mice and bone marrow clastogenicity in rodents, reported conflicting results across two or more independent tests. Two approaches were employed to evaluate and interpret the results. The first approach attempts to classify each type of genetic endpoint as positive or negative and resolve test conflicts by critical assessment of the study and detailed data. This is the more traditional “expert judgment” approach to hazard assessment. The second approach employs a computer-assisted weight-of-evidence method of data analysis. This approach does not require resolution of conflicts but uses all data sets to arrive at a classification of hazard. The first approach was able to resolve some conflicts but not all. Use of the “expert judgement” results in an equivocal conclusion and classification. Use of the weight-of-evidence method resulted in a conclusion that atrazine does not pose a mutagenic hazard. The weight-of-evidence scheme is proposed to be a more practical and relevant approach for assessing complex data sets.  相似文献   

4.
Social insect colonies provide model systems for the examination of conflicts among parties with different genetic interests. As such, they have provided the best tests of inclusive fitness theory. However, much remains unknown about in which party's favour such conflicts are resolved, partly as a result of the only recent advent of the molecular tools needed to examine the outcome of these conflicts. Two key conflicts in social insect colonies are over control of the reproductive sex ratio and the production of male offspring. Most studies have examined only one of these conflicts but in reality they occur in tandem and may influence each other. Using microsatellite analyses, the outcome of conflict over sex ratios and male production was examined in the bumble bee, Bombus hypnorum. The genotypes were determined for mother queens, their mates and males for each of 10 colonies. In contrast to other reports of mating frequency in this species, all of the queens were singly mated. The population sex ratio was consistent with queen control, suggesting that queens are winning this conflict. In contrast, workers produced over 20% of all males in queen-right colonies, suggesting that they are more effective in competing over male-production. Combining these results with previous work, it is suggested that worker reproduction is a labile trait that may well impose only small costs on queen fitness.  相似文献   

5.
6.
This study assesses land-use conflicts in the Okavango wetland ecosystem. A survey of the livelihood activities of a sample of four villages has been carried out and a stakeholder approach used to identify and analyse the key actors involved in resource competition and conflicts in the area. Traditional and emerging stakeholders were identified and found to be in conflict not only with each other but within themselves. Institutional policies on land use in the area are not properly harmonized, and there has been a top-down approach to development planning and implementation of development programmes. As a result, land-use conflicts have escalated in the area. The Okavango Delta Management Plan adopted in 2007 should integrate and harmonize all the land-use policies, and land management in the area.  相似文献   

7.
The Histone Sequence Database is an annotated and searchable collection of all available histone and histone fold sequences and structures. Particular emphasis has been placed on documenting conflicts between similar sequence entries from a number of source databases, conflicts that are not necessarily documented in the source databases themselves. New additions to the database include compilations of post-translational modifications for each of the core and linker histones, as well as genomic information in the form of map loci for the human histone gene complement, with the genetic loci linked to Online Mendelian Inheritance in Man (OMIM). The database is freely accessible through the World Wide Web at either http://genome.nhgri.nih.gov/histones/ or http://www.ncbi.nlm.nih. gov/Baxevani/HISTONES  相似文献   

8.
The paper describes factors influencing artisanal fisheries at the São Francisco River in Brazil as an example of the challenges of managing socially and economically valued common-pool resource systems. A rapid assessment of problems affecting São Francisco River fisheries in 10 communities was carried out in 2003, representing the upper, middle, and lower river portions. Field visits, interviews, focus group discussions and a literature survey allowed us to map socioeconomic and environmental factors important to the fisheries, including conflicts and tensions between stakeholders. Federal, state, and municipal governments, industries, farmers, hydroelectric companies, and urban and rural populations all have a stake in river use. Traditional fishers are the most disadvantaged of these stakeholders. With declining fish populations, most of the fishing communities surveyed are now poor, socially excluded, and with few alternative livelihood options. The stakeholders involved in access and use conflicts are artisanal fishers, professional fishers, sport fishers, farmers, enforcement and regulatory agencies, and hydroelectric companies. Traditional fishers have close ties to the river and its environment and they are usually not invited to contribute to resource management decisions. We recommend changes to management structures involving the fishing communities that are essential to resolve the major conflicts and to improve equity and sustainability of artisanal fisheries.  相似文献   

9.
With one exception, all previous studies of reconciliation in non-human primates (friendly reunion between former opponents) have focused on demonstrating the immediate, short-term effects despite the widely held view that reconciliation has a long-term function of repairing social relationships following aggression. To investigate this long-term function I compared mean interaction rates between opponents during the 10 d following reconciled and non-reconciled conflicts to baseline levels of interaction. Aggression rates during the 10 d after non-reconciled conflicts were significantly higher than the baseline rate, whereas after reconciled conflicts aggression was minimal. Similarly, grooming, proximity and approach rates during the 10 d after non-reconciled conflicts were significantly lower than the baseline rate whereas grooming, proximity and approach rates in the 10 d after reconciled conflicts were restored to baseline levels. These results indicate that there are consequences to not reconciling with a former opponent and highlight the fact that these may be costly in terms of increased risk of long-term aggression and reduced affiliation. The data support predictions from the Relationship-Repair Hypothesis suggesting that reconciliation functions as a mechanism for the repair of social relationships damaged by aggression.  相似文献   

10.
Acanthamoeba castellanii species complex (genotype T4) comprises of more than ten species with unclear synonymy. Its molecular phylogeny has several conflicts with published morphological data. In this paper, we analyze morphometric traits and temperature preferences in six new strains belonging to A. castellanii complex isolated from Arctic permafrost in the framework of molecular phylogeny. This integrative approach allows us to cross-link genotypic and phenotypic variability and identify species-level boundaries inside the complex. We also analyze previously known and newly found discrepancies between the nuclear and mitochondrial gene-based phylogenies. We hypothesize that one reason for these discrepancies may be the intragenomic polymorphism of ribosomal RNA genes.  相似文献   

11.
Hamilton's kin selection theory predicts conflicts of interestamong relatives, even within highly cooperative social insectsocieties. Because workers are the most numerous caste, collectiveworker interests may be an important force in determining theoutcome of conflicts. In this study, we used genotypes fromtwo DNA microsatellite loci to show that two kinds of collectiveworker interests are satisfied in Brachygastra mellifica, amember of the multiqueen epiponine wasps. First, from the highrelatedness of queens (0.66) and the fact that queens are singlymated (shown by genotyping their stored sperm), we calculatedthat new queens are reared in colonies with a harmonic meanof 1.2 old queens, whereas males are reared in colonies withmuch higher queen numbers. This split sex ratio result is predictedunder worker control. It matches other studies of epiponines,but B. mellifica has much larger mature colonies (averaging7951 adults) with many more queens (averaging 398), showingthe pattern holds for large-colony species. Second, we reportthe first genetic data on parentage of males in epiponines andshow that these are also consistent with collective worker interests.Workers are on average significantly more related to queensthan to other workers (r = .37 versus .23) and should thereforesuppress each other and allow the queens to lay haploid (male)eggs. Though many workers have developed ovaries and could layeggs, the genetic analyses showed that most or all males comefrom queens.  相似文献   

12.
Molecular phylogeny and evolution of the freshwater eel, genus Anguilla   总被引:3,自引:0,他引:3  
A molecular phylogenetic analysis was conducted on all of the known catadromous eel species of the genus Anguilla to assess their relationships and evolutionary history. The analyses of a total of 1427 bp of the mitochondrial 16S ribosomal RNA and 1140 bp of the complete cytochrome b gene sequences suggested that the genus Anguilla was monophyletic in origin, with A. borneensis as the most basal species. Four clades/species groups that correspond to their geographical ranges were indicated, Indo-Atlantic (three species), Oceania (two species), tropical Pacific (two species), and Indo-Pacific (five species), with ambiguous positions for A. japonica and A. reinhardti. This grouping conflicts with that of a previous morphological study, since the broad undivided maxillary and short-fin type, which were thought to be phylogenetically important, were paraphyletic in the molecular analysis. However, the molecular phylogeny and the present geographic distribution of species suggested historical dispersion of the genus Anguilla according to the Tethys corridor hypothesis, which proposed that anguillid eels originated near present-day Indonesia and dispersed westward along paleo-circumglobal equatorial currents. The westward-moving strain entered the paleo-Atlantic through the Tethys Sea and was ancestral to present-day European and American species.  相似文献   

13.
There is a growing movement to encourage reproducibility and transparency practices in the scientific community, including public access to raw data and protocols, the conduct of replication studies, systematic integration of evidence in systematic reviews, and the documentation of funding and potential conflicts of interest. In this survey, we assessed the current status of reproducibility and transparency addressing these indicators in a random sample of 441 biomedical journal articles published in 2000–2014. Only one study provided a full protocol and none made all raw data directly available. Replication studies were rare (n = 4), and only 16 studies had their data included in a subsequent systematic review or meta-analysis. The majority of studies did not mention anything about funding or conflicts of interest. The percentage of articles with no statement of conflict decreased substantially between 2000 and 2014 (94.4% in 2000 to 34.6% in 2014); the percentage of articles reporting statements of conflicts (0% in 2000, 15.4% in 2014) or no conflicts (5.6% in 2000, 50.0% in 2014) increased. Articles published in journals in the clinical medicine category versus other fields were almost twice as likely to not include any information on funding and to have private funding. This study provides baseline data to compare future progress in improving these indicators in the scientific literature.  相似文献   

14.
Abstract. Effects of form, colour, and pheromone of twospotted spider mite, Tetranychus urticae (Koch), quiescent deutonymphs on adult male guarding behaviour were tested independently and in combination using no-choice and sequential-presentation bioassays. Significantly more males approached yellow stimuli sources than non-yellow sources in all bioassays, suggesting that males orient visually to yellow carotenoid pigments of quiescent deutonymphs. The form and extract (pheromone) of quiescent deutonymphs did not increase male approach frequency. All three cues elicited male arrestment; contrasts of 2 × 3 factorial bioassay data showed that male tactile and/or visual perception of form increased arrestment frequency more than did contact chemoperception of extract, while extract perception caused more arrestments than did visual perception of colour. All three cues prolonged arrestment duration and increased frequency of intermale conflicts near stimuli sources, but form had greater impact than did other cues on the numbers of conflicts observed during coguarding incidents. Significant interactions among stimuli were observed, indicating that presence of multiple stimuli had a synergistic effect on the duration of male response. Males approached and were arrested by all three stimuli combined as often as by quiescent deutonymphs, but arrestments caused by quiescent deutonymphs were longer than those elicited by artificial stimuli. This difference suggests that either additional cues or differences in pheromone release rates are involved in eliciting and prolonging male T. urticae guarding behaviour.  相似文献   

15.
Many group living primates have evolved mechanisms to repair their social relationships after conflicts ('reconciliation'). We analysed the post-conflict behaviour of female Barbary macaques, Macaca sylvanus , living in the enclosure 'La Forêt des Singes' at Rocamadour, France. Based on a sample of 914 conflicts, we investigated whether relationship (kinship, rank, affiliation, support and sex) and conflict characteristics (conflict intensity, context and duration) affected the quality and frequency of affiliative post-conflict interactions. Thirty-two per cent of all conflicts were followed by post-conflict affiliation. Rates of socio-positive interactions and support were better predictors of post-conflict affiliation than kinship or rank. Short conflicts were followed by post-conflict affiliation relatively more frequently, after a shorter latency, but only briefly, and such interactions were initiated by both parties equally frequently. The majority of affiliative post-conflict interactions occurred immediately after the end of the conflict. In sum, female Barbary macaques invest more in post-conflict affiliation with valuable partners, and they modulate their post-conflict behaviour in relation to conflict characteristics. Remarkably, affiliative post-conflict interactions increased the short-term probability of renewed aggression by the former aggressor to 16% compared with 9% for conflicts that were not followed by affiliative behaviour. Such renewed aggression after post-conflict affiliation occurred particularly frequently among females and after conflicts over food, suggesting that post-conflict affiliation sometimes falsely lures the former victim to stay in the vicinity, even at the risk of receiving renewed aggression.  相似文献   

16.
Evolutionary conflicts among social hymenopteran nestmates are theoretically likely to arise over the production of males and the sex ratio. Analysis of these conflicts has become an important focus of research into the role of kin selection in shaping social traits of hymenopteran colonies. We employ microsatellite analysis of nestmates of one social hymenopteran, the primitively eusocial and monogynous bumblebee Bombus hypnorum, to evaluate these conflicts. In our 14 study colonies, B. hypnorum queens mated between one and six times (arithmetic mean 2.5). One male generally predominated, fathering most of the offspring, thus the effective number of matings was substantially lower (1-3.13; harmonic mean 1.26). In addition, microsatellite analysis allowed the detection of alien workers, those who could not have been the offspring of the queen, in approximately half the colonies. Alien workers within the same colony were probably sisters. Polyandry and alien workers resulted in high variation among colonies in their sociogenetic organization. Genetic data were consistent with the view that all males (n = 233 examined) were produced by a colony's queen. Male parentage was therefore independent of the sociogenetic organization of the colony, suggesting that the queen, and not the workers, was in control of the laying of male-destined eggs. The population-wide sex ratio (fresh weight investment ratio) was weakly female biased. No evidence for colony-level adaptive sex ratio biasing could be detected.  相似文献   

17.
Garrafa V  Porto D 《Bioethics》2003,17(5-6):399-416
The bioethics of the so-called 'peripheral countries' must preferably be concerned with persistent situations, that is, with those problems that are still happening, but should not happen anymore in the 21st century. Resulting conflicts cannot be exclusively analysed based on ethical (or bioethical) theories derived from 'central countries.' The authors warn of the growing lack of political analysis of moral conflicts and of human indignation. The indiscriminate utilisation of the bioethics justification as a neutral methodological tool softens and even cancels out the seriousness of several problems, even those that might result in the most profound social distortions. The current study takes as a theoretical reference the fact that natural resources (which affect us all) are relevant. Based on these premises, and on the concept that equity means 'treating unevenly the unequal', a proposal of a hard bioethics (or intervention bioethics) is introduced, in defence of the historical insights and rights of economically and socially excluded populations that are separated from the international developmental process.  相似文献   

18.
Cryptochromes (CRYs) function as blue light photoreceptors in diverse physiological processes in nearly all kingdoms of life. Over the past several decades, they have emerged as the most likely candidates for light‐dependent magnetoreception in animals, however, a long history of conflicts between in vitro photochemistry and in vivo behavioral data complicate validation of CRYs as a magnetosensor. In this review, we highlight the origins of conflicts regarding CRY photochemistry and signal transduction, and identify recent data that provides clarity on potential mechanisms of signal transduction in magnetoreception. The review primarily focuses on examining differences in photochemistry and signal transduction in plant and animal CRYs, and identifies potential modes of convergent evolution within these independent lineages that may identify conserved signaling pathways.  相似文献   

19.
青海省人与藏棕熊冲突现状、特点与解决对策   总被引:1,自引:0,他引:1  
人与野生动物冲突会造成重大经济损失,甚至造成人员伤亡,不利于野生动物的保护。藏棕熊主要分布于我国西部地区,与当地居民的冲突具有与大型食肉动物冲突的典型特点。2012-2015年我们对青海省人与藏棕熊冲突172起案件进行了统计分析,同时采用分层访谈法对86户牧民做了人与藏棕熊冲突调查,以期了解该省人与藏棕熊冲突现状,掌握冲突发生的特点和规律,探讨冲突发生的内在原因。研究结果显示:(1) 全省人与藏棕熊冲突案件集中发生在玉树州和海西州,其中玉树州治多县和曲麻莱县冲突最为严重;(2) 每年6-9月为冲突高发期,藏棕熊冬睡期的2月及11月也有发生;(3) 藏棕熊伤害类型主要表现为损毁房屋构件、取食房屋内储存的粮食以及造成人身伤亡;(4) 大部分受访者认为当地人与藏棕熊冲突事件严重,政府应以货币的形式对野生动物伤害给予适当补偿;(5) 目前牧民普遍采取的防熊措施效果并不理想。我们建议加强牧民游牧期间对房屋巡护、加固工作,建议撤户并村,妥善安置过冬食物与饲料,积极开展野生动物伤害补偿工作;同时建议进一步加强对藏棕熊的科学研究,为缓解人熊冲突现象提供科学理论依据。  相似文献   

20.
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