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1.
Structures built by animals, such as nests, mounds and burrows, are often the product of cooperative investment by more than one individual. Such structures may be viewed as a public good, since all individuals that occupy them share the benefits they provide. However, access to the benefits generated by the structure may vary among individuals and is likely to be an important determinant of social organisation. Here we use the massive, communal nests of sociable weavers Philetairus socius, to investigate whether their thermoregulatory function varies in relation to the size of communal nests, and the position of individual nest chambers within the communal structure. We then examine whether this spatial variation in thermoregulatory function predicts the social organisation of colonies. First, we show that the sociable weavers’ communal nests buffer variation in ambient temperature, and reduce temperature variability within nest chambers. The extent of this buffering effect depends significantly on the position of nest chambers within the communal structure, and on the depth to which chambers are embedded within the nest mass. We detected no effect of nest volume on thermoregulatory benefits, suggesting that there are likely to be additional, non‐thermoregulatory benefits leading to communal nests. Finally, our results indicate that there may be competition for access to the benefits of the public good, since older birds occupied the chambers with the highest thermoregulatory benefits, where breeding activity was also more common. We discuss how the spatial structure of the benefits of the public good might influence social organisation in the unique communal lifestyle of sociable weavers. 相似文献
2.
Acetobacter senegalensis belongs to the group of acetic acid bacteria (AAB) that present potential biotechnological applications, for production of D-gluconate, cellulose and acetic acid. AAB can overcome heat and acid stresses by using strategies involving the overexpression of heat-shock proteins and enzymes from the complex pyrroquinoline-ADH, besides alcohol dehydrogenases (ADH). Nonetheless, the isolation of A. senegalensis and other AAB from food may be challenging due to presence of viable but non-culturable (VBNC) cells and due to uncertainties about nutritional requirements. To contribute for a better understanding of the ecology of AAB, this paper reports on the pangenome analysis of five strains of A. senegalensis recently isolated from a Brazilian spontaneous cocoa fermentation. The results showed biosynthetic clusters exclusively found in some cocoa-related AAB, such as those related to terpene pathways, which are important for flavour development. Genes related to oxidative stress were conserved in all the genomes, with multiple clusters. Moreover, there were genes coding for ADH and putative ABC transporters distributed in core, shell and cloud genomes, while chaperonin-encoding genes were present only in the core and soft-core genomes. Regarding quorum sensing, a response regulator gene was in the shell genome, and the gene encoding for acyl-homoserine lactone efflux protein was in the soft-core genome. There were quorum quenching-related genes, mainly encoding for lactonases, but also for acylases. Moreover, A. senegalensis did not have determinants of virulence or antibiotic resistance, which are good traits for strains intended to be applied in food fermentation. 相似文献
3.
In public goods games, group members share the benefits created through individual investments. If benefits are shared equally, individual contributions readily become altruistic, and hence, a social dilemma arises in which group interests and individual interests oppose each other. However, contributions to public goods can be self‐serving if each investor gains a disproportionate benefit from its own contribution. This scenario may hold for our study system, the interactions of shoaling‐unrelated scalefin anthias Pseudanthias squamipinnis and the ectoparasitic blenny Plagiotremus tapeinosoma. The blenny bites off pieces of skin, mucus and scales from anthias that in return may chase the blenny. Chasing the blenny represents a public good as it makes the parasite change victim species for its next attack. Laboratory experiments using artificial Plexiglas hosts suggest that one reason why individuals contribute to the public good is that the blenny may specialise on non‐punishing ‘free‐riders’. Here, we investigated how far a spatial structure within the shoal and limited space use by the blenny may contribute to punishment being self‐serving. Field observation reveals that anthias indeed live in spatially structured groups and that blennies have preferred areas for attacks. Thus, some anthias individuals are consistently more exposed to blennies than others and hence may gain disproportional benefits from their punishment. In conclusion, spatial structure may contribute to the maintenance of punishment in blenny–anthias interactions even when groups are large. 相似文献
4.
Invasions biologists have frequently debated whether the definition of invasive should include ecological and economic impacts. More recent criticisms posit that objective definitions are impossible in
any absolute sense, while subjectivity is desirable for its flexibility and motivational qualities. We argue that such criticisms
underestimate the extent of subjectivity already present in invasion biology. Ecological questions may be methodological if
they relate directly to other ecological theories and models, or motivational if they focus on issues important to society
as a whole. Motivational questions are important for engaging scientists, improving public understanding of science, and often
have applied benefits. In contrast, methodological questions are constrained by established scientific theories, and are therefore
more efficient for the development of scientific knowledge. Contrary to recent critiques, we suggest that greater objectivity
is both achievable and desirable for the discipline of invasion biology and ecology generally. 相似文献
5.
Online social media such as Twitter are widely used for mining public opinions and sentiments on various issues and topics. The sheer volume of the data generated and the eager adoption by the online-savvy public are helping to raise the profile of online media as a convenient source of news and public opinions on social and political issues as well. Due to the uncontrollable biases in the population who heavily use the media, however, it is often difficult to measure how accurately the online sphere reflects the offline world at large, undermining the usefulness of online media. One way of identifying and overcoming the online–offline discrepancies is to apply a common analytical and modeling framework to comparable data sets from online and offline sources and cross-analyzing the patterns found therein. In this paper we study the political spectra constructed from Twitter and from legislators'' voting records as an example to demonstrate the potential limits of online media as the source for accurate public opinion mining, and how to overcome the limits by using offline data simultaneously. 相似文献
6.
Background: This article describes the types of community‐wide benefits provided by investigators conducting public health research in South Asia as well as their self‐reported reasons for providing such benefits. Methods: We conducted 52 in‐depth interviews to explore how public health investigators in low‐resource settings make decisions about the delivery of ancillary care to research subjects. In 39 of the interviews respondents described providing benefits to members of the community in which they conducted their study. We returned to our narrative dataset to find answers to two questions: What types of community‐wide benefits do researchers provide when conducting public health intervention studies in the community setting, and what reasons do researchers give when asked why they provided community‐wide benefits? Findings: The types of community‐wide benefits delivered were directed to the health and well‐being of the population. The most common types of benefits delivered were the facilitation of access to health care for individuals in acute medical need and emergency response to natural disasters. Respondents' self‐reported reasons when asked why they provided such benefits fell into 2 general categories: intrinsic importance and instrumental importance. 相似文献
7.
Sociobiology has revolutionized our understanding of interactions between organisms. Interactions may present a social dilemma where the interests of individual actors do not align with those of the group as a whole. Viewed through a sociobiological lens, nearly all interactions can be described regarding their costs and benefits, and a number of them then resemble a social dilemma. Numerous experimental systems, from bacteria to mammals, have been proposed as models for studying such dilemmas. Here, we make use of the external immune system of the red flour beetle, Tribolium castaneum, to investigate how the experimental duration can affect whether the external secretion comprises a social dilemma or not. Some beetles (secretors) produce a costly quinone‐rich external secretion that inhibits microbial growth in the surrounding environment, providing the secretors with direct personal benefits. However, as the antimicrobial secretion acts in the environment of the beetle, it is potentially also advantageous to other beetles (nonsecretors), who avoid the cost of producing the secretion. We test experimentally if the secretion qualifies as a public good. We find that in the short term, costly quinone secretion can be interpreted as a public good presenting a social dilemma where the presence of secretors increases the fitness of the group. In the long run, the benefit to the group of having more secretors vanishes and becomes detrimental to the group. Therefore, in such seminatural environmental conditions, it turns out that qualifying a trait as social can be a matter of timing. 相似文献
8.
The acetic acid bacteria (AAB) have important roles in food and beverage production, as well as in the bioproduction of industrial chemicals. In recent years, there have been major advances in understanding their taxonomy, molecular biology, and physiology, and in methods for their isolation and identification. AAB are obligate aerobes that oxidize sugars, sugar alcohols, and ethanol with the production of acetic acid as the major end product. This special type of metabolism differentiates them from all other bacteria. Recently, the AAB taxonomy has been strongly rearranged as new techniques using 16S rRNA sequence analysis have been introduced. Currently, the AAB are classified in ten genera in the family Acetobacteriaceae. AAB can not only play a positive role in the production of selected foods and beverages, but they can also spoil other foods and beverages. AAB occur in sugar- and alcohol-enriched environments. The difficulty of cultivation of AAB on semisolid media in the past resulted in poor knowledge of the species present in industrial processes. The first step of acetic acid production is the conversion of ethanol from a carbohydrate carried out by yeasts, and the second step is the oxidation of ethanol to acetic acid carried out by AAB. Vinegar is traditionally the product of acetous fermentation of natural alcoholic substrates. Depending on the substrate, vinegars can be classified as fruit, starch, or spirit substrate vinegars. Although a variety of bacteria can produce acetic acid, mostly members of Acetobacter, Gluconacetobacter, and Gluconobacter are used commercially. Industrial vinegar manufacturing processes fall into three main categories: slow processes, quick processes, and submerged processes. AAB also play an important role in cocoa production, which represents a significant means of income for some countries. Microbial cellulose, produced by AAB, possesses some excellent physical properties and has potential for many applications. Other products of biotransformations by AAB or their enzymes include 2-keto-L-gulonic acid, which is used for the production of vitamin C; D-tagatose, which is used as a bulking agent in food and a noncalorific sweetener; and shikimate, which is a key intermediate for a large number of antibiotics. Recently, for the first time, a pathogenic acetic acid bacterium was described, representing the newest and tenth genus of AAB. 相似文献
9.
The COVID‐19 global pandemic caused instructors to pivot to remote and online teaching, an especially challenging task in hands‐on classes such as invertebrate biology. In this special 25th anniversary issue of Invertebrate Biology, the authors present a variety of clever and effective ways to help invertebrate biology instructors adapt to teaching in an online environment. Student‐centered research and learning are essential in all biology classes, and we explore scientific writing, field trips, do‐it‐yourself laboratories, and more. These techniques will be useful for classes of varying sizes and types, from non‐major undergraduates to graduate students, even after the pandemic is over. Innovation for teaching invertebrate biology online may help facilitate more inclusive courses that serve diverse students more equitably. Ideas for how to best move traditionally hands‐on laboratories into online or remote formats are currently also being informally discussed in a collaborative online space for instructors. 相似文献
10.
Summary This paper considers public attitudes toward genetically modified plants in the fields or those soon to be planted. Analyzing
a regional public opinion survey of 680 respondents in Arkansas, Texas, Louisiana, New Mexico, and Oklahoma carried out in
the Spring—Summer of 2004, we look at the importance of public attitudes toward the three generations of agricultural biotechnology
in light of the changing regulatory environment. Specifically, we ask questions concerning the first generation of plants
with agronomic qualities, comparing our findings with previous studies, then look at perceptions of the second generation
of crops with product quality characteristics, and the third generation, which expresses industrial products and pharmaceutical
drugs. We look at perceived benefits, the likelihood, that these plants might accidentally enter the food supply, the likelihood
that these plants might be eaten by the respondent, as well as how worried and angry the respondent would be as a result.
Findings suggest that the public is still largely unaware of food biotechnology and genetically modified food products in
their life. When compared with the first and second generation agricultural biotechnology products, survey respondents indicated
that third generation products are not only likely to provide greater benefits, but are also potentially the source of more
worry and anger if accidentally eaten. 相似文献
11.
This work proposes a committee of Cascade Correlation neural networks as an online smoother for random measurement noise.
The goals of this paper are twofold: first it intends to explore the possibilities of using a constructive neural network
algorithm to learn how to filter typical noisy data from a bioreactor, CO 2 mol fractions of the effluent gas during the aerobic cultivation of Bacillus megaterium to produce the enzyme penicillin G acylase. Second, to propose a committee of such networks for achieving more realistic results,
capturing the inherent trend of the process. In order to do that this paper discusses the advantages of using a constructive
neural network algorithm, describes how the committee of NNs operates and evaluates its performance using real CO 2 online data obtained in laboratorial experiments. The paper also presents results obtained with classical filtering algorithms,
for comparison. 相似文献
12.
Mutualism can evolve when organisms make novel connections that happen to benefit all parties. When such connections involve a host that provides a public good for multiple visitor species, selection for reciprocal cooperation is only likely if the host has the power to preferentially increase the fitness of those visitors that provide a better quality service. In contrast, when interactions form between multiple visitors and a host that lacks the power to partition the public good, we predict that interactions are likely to persist only as by‐product mutualisms, in which symbiosis benefits both host and visitor, but in which neither partner makes costly investments. Focusing on the symbiosis between ants and litter trapping epiphytes in the canopy of lowland dipterocarp rain forest in Borneo, we show that at least 71 ant species share the public good of housing within the root‐mass of epiphytic bird's nest ferns ( Asplenium spp.). Ferns supporting a higher biomass of ants experienced less herbivory, and experimental exclusions of ants from fronds confirmed that this is caused by the ants protecting the ferns from herbivores. These results establish that there are clear by‐product benefits for both parties of housing for ants and protection for ferns. If these benefits were to drive selection for reciprocal cooperation, we would expect larger ferns to support ant colonies that were larger or colonies that produce more reproductive individuals. This was not the case. Larger ferns instead supported more ant colonies, indicating that the housing provided by the fern is a public good that is not restricted to better cooperating ant species. Mutualism via novel connections is thus unlikely to evolve between a host and multiple partners, even if there are clear by‐product benefits to all parties, unless the host can direct benefits to cooperators. 相似文献
13.
Environmental indicators can be used to target public programs to provide a variety of benefits. Social scientists, physical scientists, and politicians have roles in developing indicators that reflect the demands of diverse interest groups. We review the US Department of Agriculture’s Conservation Reserve Program (CRP), the largest agricultural conservation program the United States, to determine how a set of environmental indicators were developed and used, and assess results of their application. The use of such indicators has helped the CRP increase and broaden the program’s environmental benefits beyond erosion reduction, which was the primary focus of early program efforts, to meet other demands. This case study provides an example about how integration and assessment for the purpose of managing public resources requires more than natural science disciplines. Social science can help explain how public values influence what information is collected and how it is interpreted. Examples are given to show how the indices used for the CRP integrated science, politics and social values. In the end, the environmental benefits index (EBI) used to target US$ 20 billion of CRP funds reflects compromises made between science and policy considerations. It is our intention that studying this index will yield ideas and understanding from the natural science community that develops ecosystem indices about how to better plug in to programs in the future. 相似文献
14.
Insect societies headed by multiple queens (polygyny) raise evolutionary questions, such as how does genetic heterogeneity among colony members affect in-nest interactions; or, are all queens equally reproductive or equally treated by workers? Answering such questions requires intensive and continuous observations of in-nest behavior. Here, we addressed these questions in the polygyne supercolonial ant, Cataglyphis niger, using a barcoding system that enables the tracking of individual interactions, together with polymorphic DNA microsatellite markers that indicate the matriline and patriline of all individuals. Our findings that both queens and workers have low interrelatedness corroborate earlier reports regarding the supercolony structure of C. niger. Ovary inspection and worker genotyping revealed that all the queens contribute similarly to nest demography. Tracking positions of individual workers through time revealed that only a small proportion of them are constantly engaged in tending the queens and can be considered as retinue workers. However, genotyping these workers and the attended queens revealed no relationship to genetic relatedness, again typical of a true polygyne and supercolonial species. Unlike invasive supercolonial species, C. niger is native to Israel, enabling us to address questions regarding the driving forces, other than kin selection, that stabilize this society. 相似文献
15.
This editorial announces Algorithms for Molecular Biology, a new online open access journal published by BioMed Central. By launching the first open access journal on algorithmic
bioinformatics, we provide a forum for fast publication of high-quality research articles in this rapidly evolving field.
Our journal will publish thoroughly peer-reviewed papers without length limitations covering all aspects of algorithmic data
analysis in computatioal biology. Publications in Algorithms for Molecular Biology are easy to find, highly visible and tracked by organisations such as PubMed. An established online submission system makes
a fast reviewing procedure possible and enables us to publish accepted papers without delay. All articles published in our
journal are permanently archived by PubMed Central and other scientific archives. We are looking forward to receiving your
contributions. 相似文献
16.
Dispersal (i.e. movement from a natal or breeding site to another breeding site) is a central process in ecology and evolution as it affects the eco‐evolutionary dynamics of spatially structured populations. Dispersal evolution is regulated by the balance between costs and benefits, which is influenced by the individual phenotype (i.e. phenotype‐dependent dispersal) and environmental factors (i.e. condition‐dependent dispersal). Even though these processes have been extensively studied in species with simple life cycles, our knowledge about these mechanisms in organisms displaying complex life cycles remains fragmentary. In fact, little is specifically known about how the interplay between individual and environmental factors may lead to alternative dispersal strategies that, in turn, lead to the coexistence of contrasted site fidelity phenotypes. In this paper, we examined breeding dispersal in a pond‐breeding amphibian, the great crested newt Triturus cristatus, within usual walking distances for a newt. We took advantage of recent developments in multi‐event capture–recapture models and used capture–recapture data (946 newts marked) collected in a spatially structured population occupying a large pond network (73 ponds). We showed a high rate of breeding site infidelity (i.e. pond use) and the coexistence of two dispersal phenotypes, namely, a highly pond faithful phenotype and a dispersing phenotype. Individuals that were site faithful at time t – 1 were therefore more likely to remain site faithful at time t. Our results also demonstrated that the probability that individuals belong to one or the other dispersal phenotypes depended on environmental and individual factors. In particular, we highlighted the existence of a dispersal syndrome implying a covariation pattern among dispersal behavior, body size, and survival. Our work opens new research prospects in the evolution of dispersal in organisms displaying complex life cycles and raises interesting questions about the evolutionary pathways that contribute to the diversification of movement strategies in the wild. 相似文献
17.
In this paper, we draw the attention of biologists to a result from the economic literature, which suggests that when individuals are engaged in a communal activity of benefit to all, selection may favour cooperative sharing of resources even among non-relatives. Provided that group members all invest some resources in the public good, they should refrain from conflict over the division of these resources. The reason is that, given diminishing returns on investment in public and private goods, claiming (or ceding) a greater share of total resources only leads to the actor (or its competitors) investing more in the public good, such that the marginal costs and benefits of investment remain in balance. This cancels out any individual benefits of resource competition. We illustrate how this idea may be applied in the context of biparental care, using a sequential game in which parents first compete with one another over resources, and then choose how to allocate the resources they each obtain to care of their joint young (public good) versus their own survival and future reproductive success (private good). We show that when the two parents both invest in care to some extent, they should refrain from any conflict over the division of resources. The same effect can also support asymmetric outcomes in which one parent competes for resources and invests in care, whereas the other does not invest but refrains from competition. The fact that the caring parent gains higher fitness pay-offs at these equilibria suggests that abandoning a partner is not always to the latter''s detriment, when the potential for resource competition is taken into account, but may instead be of benefit to the ‘abandoned’ mate. 相似文献
18.
High-density lipoprotein cholesterol (HDL-C) is a known inverse predictor of coronary heart disease (CHD) and is thus a potential
therapeutic target. Cholesteryl ester transfer protein (CETP) is a key protein in HDL-C metabolism such that elevated CETP
activity is associated with lower HDL-C. Currently available HDL-C raising drugs are relatively ineffective and evidence suggesting
the role of CETP in HDL-C levels has promoted the development of CETP inhibitors as potential therapeutic agents for CHD.
We investigated three SNPs in the CETP gene in two cross-sectional community-based populations ( n = 1,574 and 1,109) and a population of 556 CHD patients to determine if reduced CETP activity due to genetic variations in
the CETP gene would increase HDL-C levels and reduce the risk of CHD. CETP genotypes and haplotypes were tested for association
with lipid levels, CETP activity and risk of CHD. Multivariate analysis showed the common AAB2 haplotype defined by the G-2708A,
C-629A and TaqIB polymorphisms, was consistently associated with reduced CETP activity and increased HDL-C levels. A mean increase in HDL-C
levels of 0.16–0.24 mmol/l was observed in individuals with two copies of the AAB2 haplotype relative to non AAB2 carriers
across all three populations ( P < 0.001). A case-control study of males indicated no association between single SNPs or haplotypes and the risk of CHD. These
results suggest that raising HDL-C via CETP inhibition may not alter risk of CHD. Randomized control trials are needed to
determine whether CETP inhibition will in reality reduce risk of CHD by raising HDL-C.
Pamela A. McCaskie and John P. Beilby contributed equally to this work. 相似文献
19.
Since the dawn of civilisation visual communication played a role in everyday life. In the early times there were simply shaped drawings of animals, pictograms explaining hunting tactics or strategies of attacking the enemies. Through evolution visual expression becomes an important component of communication process on several levels, from the existential and economic level to the artistic level. However, there was always a question of the level of user reception of such visual information in the medium transmitting the information. Does physical positioning of information in the medium contribute to the efficiency of the message? Do the same rules of content positioning apply for traditional (offline) and online media (Internet)? Rapid development of information technology and Internet in almost all segments of contemporary life calls for defining the rules of designing and positioning multimedia online contents on web sites. Recent research indicates beyond doubt that the physical positioning of an online content on a web site significantly determines the quality of user's perception of such content. By employing the "Eye tracking" method it is possible to objectively analyse the level of user perception of a multimedia content on a web site. What is the first thing observed by the user after opening the web site and how does he/she visually search the online content? By which methods can this be investigated subjectively and objectively? How can the survey results be used to improve the creation of web sites and to optimise the positioning of relevant contents on the site? The answers to these questions will significantly improve the presentation of multimedia interactive contents on the Web. 相似文献
20.
Mass media has always been a prominent source of science information for the general public, and more so than academic journals.
The diversification of media with specialized online outlets and the participatory nature of the Internet have opened opportunities,
as well as challenges, for researchers and educators. This paper represents our attempt to address this issue with respect
to human evolutionary behavioral sciences, and suggest ways to successfully navigate interactions with the mass media for
effective evolutionary education. We briefly review how one can interact with the mass media for educational purposes, focusing
on how best to situate one’s research within evolutionary theory. We describe our own experiences and those of other academic
colleagues who have received mass media attention, noting both positive and negative results. We also provide specific tips
on how to best interact with various forms of media. 相似文献
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