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1.
Abstract

The Xylocopinae contains four tribes with species which show a range of nesting habits, from solitary to social. The Manueliini is the sister group to all other Xylocopine tribes, with one genus, Manuelia, of three species found mainly in Chile. This is a solitary genus, whose biology is scarcely known for two species, M. gayatina and M. gayi, and so far completely unknown for M. postica. This paper reports on nesting substrates, nest architecture, nesting behaviours, life cycle, and interactions between females at nesting sites, for M. postica. The results indicate that M. postica presents some features which are typical of solitary life, and also some features which are unusual in solitary bees but have been reported in phylogenetically more apical social species. Our findings open interesting questions on the ecological scenarios involved in the evolution of sociality within the Xylocopinae.  相似文献   

2.
Abstract

This study used the FACES 2009 cohort to examine the effect of classroom language diversity on the social-emotional development (defined as social skills, approaches to learning, and behavior problems) of the ELL and non-ELL children. A three-level hierarchical linear modeling in which time was nested within the child and the child was nested within the classroom was conducted. The children’s ELL status was determined based on their home language and English proficiency. Results showed that the non-ELL children demonstrated a decline in the developmental trajectory of social skills in the classrooms with high language diversity. On the other hand, the ELL children with English proficiency demonstrated a low trajectory of social skills in the classrooms with low language diversity. These findings suggest that the effect of classroom language diversity on the children’s social-emotional development depends on the children’s language status. Implications and future research are discussed.  相似文献   

3.
目的 探讨导致医患信任危机的多维影响因素与解决策略。方法 运用文献研究、专家咨询、现场调查及因子分析的方法,寻找对医患关系信任构成重要影响的潜在公因子,分析医患信任危机的成因。结果 医疗服务因子、医疗纠纷调解与行业监管因子、社会制度因素及文化价值因子、医患沟通因子是驱动医患信任危机形成的主因。结论 医患信任危机的形成受到医疗服务过程、外部社会制度及文化观念、行业监管及医患沟通和互动等多重因素的影响,需要政府、医疗机构和全社会共同努力,消解医患信任危机的坚冰,促进医患关系修复与和谐。  相似文献   

4.
Well-characterized species introductions provide opportunities to compare the genetic signatures of known founder effects across classes of molecular markers. The release of small numbers of house finches (Carpodacus mexicanus) into the eastern United States in the 1940s led to substantial interest in the effects of this introduction on genetic diversity in this now abundant species, an issue that has been highlighted by a recent Mycoplasma disease epidemic that most intensively affects the introduced and potentially genetically depauperate house finch populations. Previous studies comparing genetic diversity levels in native and introduced house finch populations produced seemingly disparate results: comparisons based on amplified fragment length polymorphism, RFLP mtDNA, and allozyme markers found essentially equivalent levels of diversity in eastern and western populations, whereas microsatellite markers showed clear reductions in diversity in the introduced populations. Here we employ sequence variation at the ND2 mtDNA locus to further compare levels of diversity between the four native and five introduced house finch populations that were previously examined in the microsatellite study. We found substantially lower ND2 haplotype richness and diversity across all introduced populations of house finches. The majority of sequence variation (78%) was detected within subpopulations, with the remainder (22%) explained by the historical status of each population (native or introduced). Our results are consistent with previous microsatellite evidence for a founder effect during the introduction of eastern house finches, and suggest that the mtDNA founder effect was particularly severe, likely owing to a male-biased sex ratio at the time of introduction coupled with the lower effective population size of clonally inherited markers. We discuss how the inconsistencies between past studies of house finch diversity can inform the usefulness of distinct marker sets for detecting molecular signatures of founder events.  相似文献   

5.
Background: Species-rich Nardus stricta grasslands are a priority habitat for conservation in Europe. They typically occur on siliceous substrates and less frequently are found on calcareous bedrock.

Aims: The present paper aimed to identify the environmental factors (i.e. bedrock type, topographic, and climatic factors) that are related with community diversity and to assess if differences in plant diversity between N. stricta communities on calcareous and siliceous bedrock occur. We hypothesised that Nardus grasslands on calcareous bedrock hosted a higher vascular plant diversity than those on siliceous bedrock.

Methods: Based on 579 vegetation surveys carried out in the south-western Alps, we assessed vascular plant diversity (species richness, Shannon diversity, and Pielou’s equitability index) of species-rich Nardus grasslands and compared it between N. stricta communities on calcareous and siliceous bedrock.

Results: Elevation was identified as the main factor related to species composition, while species diversity was mostly related to mean annual precipitation and bedrock type. Species richness, Shannon diversity, and Pielou’s equitability index were higher within the communities on calcareous rather than on siliceous bedrock and a total of 89 and 34 indicator species were detected, respectively.

Conclusions: Based on our results, we suggest to protect primarily, as a habitat of priority interest, N. stricta grasslands on calcareous substrates for the higher vascular plant diversity hosted.  相似文献   

6.
Aim To reassess the relationships between Tarentola geckos from the Cape Verde Islands by including specimens from all islands in the range. To determine the variation within forms by sequencing over 400 specimens, thereby allowing the discovery of cryptic forms and resolving some of the issues raised previously. This extensive sampling was also used to shed light on distributions and to explain genetic diversity by comparing the ages and ecological and geological features of the islands (size, elevation and habitat diversity). Location The Cape Verde Islands: an oceanic archipelago belonging to the Macaronesian biogeographic region, located around 500 km off Senegal. Methods A total of 405 new specimens of Tarentola geckos were collected from nine islands with very different geological histories, topography, climate and habitats. Mitochondrial cytochrome b (cyt b) gene and 12S rRNA partial sequences were obtained and analysed using phylogenetic methods and networks to determine molecular diversity, demographic features and phylogeographic patterns. Results The phylogenetic relationships between all known forms of Cape Verdean Tarentola specimens were estimated for the first time, the relationships between new forms were assessed and previously hypothesized relationships were re‐examined. Despite the large sample size, low intraspecific diversity was found using a 303‐bp cyt b fragment. Star‐like haplotype networks and statistical tests suggest the past occurrence of a rapid demographic and geographical expansion over most of the islands. Genetic variability is positively correlated with size, elevation and habitat diversity of the islands, but is not linearly related to the age of the islands. Biogeographical patterns have, in general, high concordance with phylogenetic breaks and with the three eco‐geographical island groups. Volcanism and habitat diversity, both tightly linked with island ontogeny, as postulated by the general dynamic model of oceanic island biogeography, as well as present and historical size of the islands appear to be the main factors explaining the genetic diversity of this group. Main conclusions The Tarentola radiation was clarified and is clearly associated with the geological and ecological features of the islands. Two factors may account for the low intraspecific variation: (1) recent volcanic activity and high ecological stress, and (2) poor habitat diversity within some islands. More studies are needed to align taxonomy with phylogenetic relationships, whereas GIS modelling may help to predict precise species distributions.  相似文献   

7.
Interactions between the structure of a metabolic network and its functional properties underlie its evolutionary diversification, but the mechanism by which such interactions arise remains elusive. Particularly unclear is whether metabolic fluxes that determine the concentrations of compounds produced by a metabolic network, are causally linked to a network's structure or emerge independently of it. A direct empirical study of populations where both structural and functional properties vary among individuals’ metabolic networks is required to establish whether changes in structure affect the distribution of metabolic flux. In a population of house finches (Haemorhous mexicanus), we reconstructed full carotenoid metabolic networks for 442 individuals and uncovered 11 structural variants of this network with different compounds and reactions. We examined the consequences of this structural diversity for the concentrations of plumage‐bound carotenoids produced by flux in these networks. We found that concentrations of metabolically derived, but not dietary carotenoids, depended on network structure. Flux was partitioned similarly among compounds in individuals of the same network structure: within each network, compound concentrations were closely correlated. The highest among‐individual variation in flux occurred in networks with the strongest among‐compound correlations, suggesting that changes in the magnitude, but not the distribution of flux, underlie individual differences in compound concentrations on a static network structure. These findings indicate that the distribution of flux in carotenoid metabolism closely follows network structure. Thus, evolutionary diversification and local adaptations in carotenoid metabolism may depend more on the gain or loss of enzymatic reactions than on changes in flux within a network structure.  相似文献   

8.
Background

Maternally inherited bacterial symbionts infecting arthropods have major implications on host ecology and evolution. Among them, the genus Arsenophonus is particularly characterized by a large host spectrum and a wide range of symbiotic relationships (from mutualism to parasitism), making it a good model to study the evolution of host-symbiont associations. However, few data are available on the diversity and distribution of Arsenophonus within host lineages. Here, we propose a survey on Arsenophonus diversity in whitefly species (Hemiptera), in particular the Bemisia tabaci species complex. This polyphagous insect pest is composed of genetic groups that differ in many ecological aspects. They harbor specific bacterial communities, among them several lineages of Arsenophonus, enabling a study of the evolutionary history of these bacteria at a fine host taxonomic level, in association to host geographical range and ecology.

Results

Among 152 individuals, our analysis identified 19 allelic profiles and 6 phylogenetic groups, demonstrating this bacterium's high diversity. These groups, based on Arsenophonus phylogeny, correlated with B. tabaci genetic groups with two exceptions reflecting horizontal transfers. None of three genes analyzed provided evidence of intragenic recombination, but intergenic recombination events were detected. A mutation inducing a STOP codon on one gene in a strain infecting one B. tabaci genetic group was also found. Phylogenetic analyses of the three concatenated loci revealed the existence of two clades of Arsenophonus. One, composed of strains found in other Hemiptera, could be the ancestral clade in whiteflies. The other, which regroups strains found in Hymenoptera and Diptera, may have been acquired more recently by whiteflies through lateral transfers.

Conclusions

This analysis of the genus Arsenophonus revealed a diversity within the B. tabaci species complex which resembles that reported on the larger scale of insect taxonomy. We also provide evidence for recombination events within the Arsenophonus genome and horizontal transmission of strains among insect taxa. This work provides further insight into the evolution of the Arsenophonus genome, the infection dynamics of this bacterium and its influence on its insect host's ecology.

  相似文献   

9.
Reef corals associate with an extraordinary diversity of dinoflagellate endosymbionts (genus Symbiodinium), and this diversity has become critical to understanding how corals respond to environmental changes. A popular molecular marker for Symbiodinium diversity, the Internal Transcribed Spacer-2 (ITS-2) region of ribosomal DNA, has revealed hundreds of distinct variants that are generally interpreted as representing different species, even though many have not been systematically tested for functional or ecological differentiation. Many of these variants are only minimally divergent from one another (1 bp or less), and others occupy basal nodes of traditional species phylogenies (“living ancestors”), indicating that some Symbiodinium ITS-2 diversity may represent intraspecific sequence variation. This hypothesis was tested for Symbiodinium clades AD (the dominant symbionts of reef corals) through the construction of statistical parsimony networks of ITS-2 sequence diversity, and identification of clusters of closely related sequences within these networks. Initial assessments indicated that ecological differentiation exists between, but not within, these clusters. This approach, although imperfect in its ability to identify species boundaries in all cases, nevertheless dramatically reduces “species” diversity in Symbiodinium (from ~175 to 35). This testable alternative hypothesis indicates that, in Symbiodinium, “species” consist of clusters of closely related ITS-2 sequences diverging from ancestral variants that are typically ecologically dominant. A cluster-based view of Symbiodinium ITS-2 diversity improves our ability to: (1) construct well-supported symbiont phylogenies; (2) establish functional niches for symbiont species; and (3) understand flexibility and specificity within coral-algal symbioses. This cluster-based approach can ultimately be integrated with emerging population-level datasets (microsatellites and microsatellite flanking regions) to improve understanding of species diversity in Symbiodinium. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Communicated by Biology Editor Dr Ruth Gates  相似文献   

10.
ABSTRACT

This article explores how parents include other people’s children in intensive parenting practices. Increased diversification of Norwegian society calls attention to opportunities for social mobility and the risk of greater inequality. However, insufficient research has been carried out into how parents pursue parenting in such a context. How are parenting practices informed by increased diversity? Why and how do parents become engaged with other people’s children? This study explores the concept of intensive parenting, which researchers view as commonplace among Western middle-class parents, and which leads to individualizing parenting. It argues that for some, intensive parenting also incorporates inclusive parenting – a responsibility not only towards their own child, but a concern for and time investment in other people’s children. This parenting style is linked to a desire to create a more egalitarian society, and a belief that a child’s upbringing and future depends upon the wellbeing of other people’s children.  相似文献   

11.
The ecological consequences of homogenization remain relatively unexplored. One example of landscape-homogenizing is the establishment of plantations. We studied the effect of human-made forests by contrasting plant and small-mammal community composition between planted tree stands and adjacent natural habitat in two different Mediterranean habitats in Israel: (1) inland habitat where we focused on pine (Pinus halepensis) and carob (Ceratonia siliqua) stands, and (2) coastal sand dune habitat where we focused on planted acacia (Acacia saligna) stands. We first wanted to verify whether planted trees modify plant species composition, and second, if and how the small-mammal community is affected by the different habitat conditions created in plantations with different canopy cover. We were especially interested in the abundance of the commensal house mouse (Mus musculus). All tree stands underwent biotic homogenization indicated by abundance of house mice coupled with lower diversity of indigenous vegetation and small-mammal abundances and diversities. Habitat structural diversity was positively related with small-mammals diversity and was lower in artificial tree stands in both habitats. Our results suggest that using the abundance of commensal generalist species such as the house mouse relative to other more specialist small-mammals is a good approach to determine ecosystem integrity. Pre-commercial thinning treatment is a potential management tool to maintain a proportion of native tree species within the canopy of planted tree stands. However, until sufficient data is available for making generalizations, the exact level of thinning necessary to reverse the homogenization processes in man-made plantations and keeping indigenous small-mammal communities diverse and less prone to invasion must be determined empirically.  相似文献   

12.
The elaborate songs of male animals are thought to function in either territory defense (male–male communication) or mate attraction (male–female communication). In non‐territorial animals, male vocalizations are expected to function primarily in mate attraction, yet the reproductive consequences of male vocalizations in non‐territorial animals are poorly described. Here we explore the relationship between male song and male reproductive performance in a free‐living population of house finches, Carpodacus mexicanus, a non‐migratory, non‐territorial songbird. Based on recordings of 20 males, we analyzed three song features (song length, number of unique syllables per song, and song rate) and compared male song with two measures of within‐pair reproductive performance (nest initiation date and clutch size) and one measure of extra‐pair reproductive performance (whether males sired extra‐pair young). We demonstrate a positive association between male song and within‐pair reproductive performance; males that sang long songs initiated their first clutch significantly earlier and males that sang songs at a faster rate had larger clutches. Despite the fact that only one of our recorded males sired extra‐pair young in the nest of another male, this male's songs were the most elaborate for two of three song features measured, anecdotally suggesting that male song may play a role in both within‐pair and extra‐pair partner choice. These results suggest that male song is a sexually selected trait in non‐territorial house finches.  相似文献   

13.
Vocal signals mediate social relationships, and among networks of territorial animals, information is often shared via broadcast vocalizations. Anthropogenic noise may disrupt communication among individuals within networks, as animals change the way they vocalize in noise. Furthermore, constraints on signal transmission, including frequency masking and distance, may affect information exchange following a disruption in social networks. We tested the hypothesis that signaling interactions within networks of breeding male and female house wrens (Troglodytes aedon) depend on distance, ambient noise, and receiver nesting stage. We used playback experiments to simulate territorial intrusions with and without noise playbacks on the territories of established males and simultaneously recorded the vocal responses of neighbors. To examine whether intrusions impacted interactions between males, we used randomization tests to determine whether treatment, distance, noise, or nesting stage affected vocal coordination between challenged and neighboring males. We also quantified singing patterns to explore whether intrusions on territories of challenged males affected singing by males and females on neighboring territories. Males sang at the lowest rates and were less likely to overlap songs with the challenged male when their partner was laying, compared to males during early and late nesting stages. Noise and distance did not affect vocal coordination or male singing rates. Fewer females sang during the intruder-only treatment compared to the control and intrusions with noise. Added noise in the territories of challenged males may have masked signals, and as a result, females only changed their behavior during the intruder-only treatment. Our results suggest that the fertility of breeding partners may be more important to males than short-term changes on rival male territories. Elevated noise did little to alter male responses to threats within networks. Females appeared to eavesdrop on interactions involving neighboring males, but noise may have prevented detection of their interactions.  相似文献   

14.
Abstract

The public concern about electromagnetic field (EMF) exposure varies due to different reasons. A part of them are connected with the better and higher quality of information that people receive from science, media, Internet, social networks, industry, but others are based on good communication programs performed by the responsible institutions, administration and persons. Especially, in Bulgaria, public concern follows interesting changes, some of them in correlation with the European processes of concern, but others following the economic and political processes in the country. Here, we analyze the dynamics of the public concern over the last 10 years. Our explanation of the decrease of the people’s complaints against EMF exposure from base stations for mobile communication is as a result of our risk communication program that is in implementation for >10 years.  相似文献   

15.
Among rhesus macaques (Macaca mulatta)and other cercopithecine monkeys, social groups occupying adjacent home ranges (i.e., members of the same local population) exchange individuals and genes and thus exhibit marked genetic similarities. To assess the degree to which this pattern extends beyond the local population, the genetic structure of M. mulattaand six other primate species was determined using Nei’s (1973) gene-diversity analysis. The genetic similarities seen among social groups in the Dunga Gali population of M. mulatta (Melnick et al.,1984a) can be seen over the entire species range. Comparison of these results with the structures of other similarly organized primate species indicates that (1) the average social group contains most of its local population’s genetic diversity, (2) the average local population contains the majority of the genetic diversity found in the region to which it belongs, and (3) the proportion of species gene diversity found in the average regional population varies substantially between species. Genetic homogeneity within local and regional populations is probably the product of gene flow. The application of a number of analytical models of selection and gene flow strongly suggests that gene flow, genetic drift, and zoogeography offer a more parsimonious and plausible explanation for interspecific variation in regional differentiation than does stabilizing selection.  相似文献   

16.
Júlio M. Neto 《Bird Study》2013,60(2):171-176
Capsule Savi's Warblers preferred sites dominated by high and dense Juncus and Rubus with thick litter, and avoided pure reeds; predation was higher in sites with less litter.

Aim To describe nest-site selection and identify which habitat and nest features influence predation risk.

Methods Comparisons were made between habitat characteristics measured at nest-sites and random points, and between predated and successful nests.

Results Total vegetation cover, litter thickness, habitat type, undergrowth height and undergrowth cover, which were higher or denser at nest-sites, were the most important variables influencing the distribution of Savi's Warbler nests. Nests were most often predated in sites with low litter thickness.

Conclusion Savi's Warblers are dependent on the presence of dense low vegetation and litter for nesting, which should be maintained close to or within reed-beds for their benefit.  相似文献   

17.
The lizard genus Egernia has been suggested as an excellent model system for examining the evolution of sociality as it exhibits considerable diversity in social organization both between and within species. To date the majority of work examining the factors responsible for the evolution of sociality within Egernia has advocated a broad scale approach; identifying the social structure of specific species or populations and comparing the degree of sociality between them. However, we argue that significant advancements could also be gained by examining variation in social strategies within populations. Here we integrate a detailed, 3‐year, field‐based examination of social spacing and juvenile dispersal with molecular analyses of paternity to determine the social and mating system of a Tasmanian population of White's skink (Egernia whitii). We show that E. whitii live in small stable family groups consisting of an adult male, his female partner(s), as well as juvenile or sub‐adults individuals. In addition, while the mating system is characterized by considerable genetic monogamy, extra‐pair fertilizations are relatively common, with 34% of litters containing offspring sired by males from outside the social group. We also show that traits related to social organization (social group composition, group size, stability and the level of extra‐pair paternity) vary both between and within individuals. We suggest that ecological factors, such as habitat saturation, quality and availability, play a key role in maintaining between individual variation in social strategies, and that examining these individual level processes will allow us to more clearly understand variation in sociality among species.  相似文献   

18.
Richard Vokes 《Ethnos》2018,83(2):274-290
ABSTRACT

This article contributes to recent attempts to provide ethnographically and historically nuanced accounts of Africa's mobile phone ‘revolution’. It does so by examining the coming of mobile phones in one particular place and time: Bugamba Sub-County, in rural Mbarara District, South-western Uganda, between the years 2000 and 2012. In so doing, it extends recent anthropological scepticism regarding the transformative potential of mobile communication per se, by showing how in this case, the most notable effects generated by mobile telephony were in fact those produced by a series of exchanges of phone-related objects, which took place in a sense ‘prior’ to communication. These circulations effected a kind of ‘time–space expansion’, which allowed for new imaginaries of physical and social mobility. The article illustrates these arguments through a detailed examination of the mobile spaces of taxis, and through a discussion of changing burial practices.  相似文献   

19.
ABSTRACT

The acoustic communication of three species of social voles from the subgenus SumeriomysMicrotus socialis (two subspecies: M. s. socialis and M. s. goriensis), M. paradoxus and M. hartingi – are described. Vole sound communication includes two main signals: squeaks and singing. The sounds made by M. hartingi have significantly higher frequency parameters than those of other species. Voles of all species squeak in situations of distress, and the males sing during courtship of the females. However, singing in social voles is not a necessary pattern for sexual behaviour: less than half of M. s. socialis and M. paradoxus males sang, M. hartingi sang even more rarely and M. s. goriensis did not demonstrate this behaviour at all. Despite the great similarity of the squeaks, its parameters differ significantly between species and differ from those of the common voles. This introduces one more argument that M. paradoxus and M. socialis are independent species, as are the subgenera Sumeriomys and Microtus.  相似文献   

20.
王正  王石垒  吴群  徐岩 《微生物学通报》2021,48(11):4167-4177
[背景] 在白酒发酵过程中,原料中的谷物蛋白可为微生物的生长提供氮源等营养物质,进而形成多种代谢产物。谷物蛋白可分为清蛋白、球蛋白、醇溶蛋白和谷蛋白。然而,谷物蛋白对微生物多样性及其代谢产物多样性的调控尚不明确。[目的] 揭示白酒发酵过程中与微生物多样性及其代谢产物多样性显著相关的关键谷物蛋白种类及其调控作用。[方法] 通过Osborne法测定不同品种高粱中谷物蛋白的组成;采用多组学联用技术解析4种高粱在发酵过程中的微生物菌群多样性及代谢产物多样性;通过模拟发酵揭示原料中影响微生物群落及其代谢多样性的关键蛋白。[结果] 4种高粱中的谷物蛋白组成存在显著差异(ANOSIM:R=0.85,P=0.001);4种高粱在发酵第5天时,S4高粱的细菌多样性显著(P<0.05)高于其他3种高粱,S3高粱中微生物的代谢产物多样性显著(P<0.05)高于其他3种高粱;清蛋白和球蛋白含量与发酵第5天的优势细菌多样性(R2=0.34,P<0.05;R2=0.58,P<0.05)和代谢产物多样性呈显著正相关(R2=0.58,P<0.05;R2=0.36,P<0.05),被定义为关键蛋白;模拟发酵实验验证了优势细菌多样性和代谢产物多样性可随着2种关键蛋白即清蛋白和球蛋白含量的升高而升高。当清蛋白含量在3.0 g/L时,优势细菌多样性及代谢产物多样性可分别达到0.72和0.65;当球蛋白含量在3.0 g/L时,优势细菌多样性及代谢产物多样性可分别达到0.66和0.81。[结论] 研究揭示了酿造原料中的清蛋白和球蛋白对发酵过程中细菌多样性及代谢产物多样性的调控作用,为提高白酒发酵的可控性及质量提供了依据。  相似文献   

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