scholarly journals Comparative Analyses of Vertebrate Gut Microbiomes Reveal Convergence between Birds and Bats

mBio ◽  
2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Se Jin Song ◽  
Jon G. Sanders ◽  
Frédéric Delsuc ◽  
Jessica Metcalf ◽  
Katherine Amato ◽  
...  
Keyword(s):  
Gut Microbiome ◽  
Cost Benefit ◽  
Phylogenetic Distance ◽  
Strong Correlations ◽  
Evolutionary Relatedness ◽  
Host Diet ◽  
Comprehensive Survey ◽  
Taxonomic Range ◽  
Host Phylogeny ◽  
The Cost

ABSTRACT Diet and host phylogeny drive the taxonomic and functional contents of the gut microbiome in mammals, yet it is unknown whether these patterns hold across all vertebrate lineages. Here, we assessed gut microbiomes from ∼900 vertebrate species, including 315 mammals and 491 birds, assessing contributions of diet, phylogeny, and physiology to structuring gut microbiomes. In most nonflying mammals, strong correlations exist between microbial community similarity, host diet, and host phylogenetic distance up to the host order level. In birds, by contrast, gut microbiomes are only very weakly correlated to diet or host phylogeny. Furthermore, while most microbes resident in mammalian guts are present in only a restricted taxonomic range of hosts, most microbes recovered from birds show little evidence of host specificity. Notably, among the mammals, bats host especially bird-like gut microbiomes, with little evidence for correlation to host diet or phylogeny. This suggests that host-gut microbiome phylosymbiosis depends on factors convergently absent in birds and bats, potentially associated with physiological adaptations to flight. Our findings expose major variations in the behavior of these important symbioses in endothermic vertebrates and may signal fundamental evolutionary shifts in the cost/benefit framework of the gut microbiome. IMPORTANCE In this comprehensive survey of microbiomes of >900 species, including 315 mammals and 491 birds, we find a striking convergence of the microbiomes of birds and animals that fly. In nonflying mammals, diet and short-term evolutionary relatedness drive the microbiome, and many microbial species are specific to a particular kind of mammal, but flying mammals and birds break this pattern with many microbes shared across different species, with little correlation either with diet or with relatedness of the hosts. This finding suggests that adaptation to flight breaks long-held relationships between hosts and their microbes.

scholarly journals Host diet and evolutionary history explain different aspects of gut microbiome diversity among vertebrate clades

2018 ◽  
Author(s):  
Nicholas D. Youngblut ◽  
Georg H. Reischer ◽  
William Walters ◽  
Nathalie Schuster ◽  
Chris Walzer ◽  
...  
Keyword(s):  
Microbial Community ◽  
Community Assembly ◽  
Gut Microbiome ◽  
Evolutionary History ◽  
Environmental Filtering ◽  
Microbiome Diversity ◽  
Host Diet ◽  
Host Phylogeny ◽  
Microbe Interactions ◽  
Microbial Community Assembly

AbstractMultiple factors modulate microbial community assembly in the gut, but the magnitude of each can vary substantially across studies. This may be in part due to a heavy reliance on captive animals, which can have very different gut microbiomes versus their wild counterparts. In order to better resolve the influence of evolution and diet on gut microbiome diversity, we generated a large and highly diverse animal distal gut 16S rRNA microbiome dataset, which comprises 80 % wild animals and includes members of Mammalia, Aves, Reptilia, Amphibia, and Actinopterygii. We decoupled the effects of host evolutionary history and diet on gut microbiome diversity and show that each factor explains different aspects of diversity. Moreover, we resolved particular microbial taxa associated with host phylogeny or diet, and we show that Mammalia have a stronger signal of cophylogeny versus non-mammalian hosts. Additionally, our results from ecophylogenetics and co-occurrence analyses suggest that environmental filtering and microbe-microbe interactions differ among host clades. These findings provide a robust assessment of the processes driving microbial community assembly in the vertebrate intestine.

scholarly journals Phylosymbiosis across Deeply Diverging Lineages of Omnivorous Cockroaches (Order Blattodea)

2020 ◽  
Vol 86 (7) ◽  
Author(s):  
Kara A. Tinker ◽  
Elizabeth A. Ottesen
Keyword(s):  
Gut Microbiota ◽  
Significant Role ◽  
Gut Microbiome ◽  
Host Species ◽  
Evolutionary Divergence ◽  
Phylogenetic Distance ◽  
Evolutionary Time ◽  
Microbiome Composition ◽  
Ancient Lineage ◽  
Host Phylogeny

ABSTRACT The gut microbiome is shaped by both host diet and host phylogeny. However, separating the relative influence of these two factors over long periods of evolutionary time is often difficult. We conducted a 16S rRNA gene amplicon-based survey of the gut microbiome from 237 individuals and 19 species of omnivorous cockroaches from the order Blattodea. The order Blattodea represents an ancient lineage of insects that emerged over 300 million years ago, have a diverse gut microbiota, and have a typically gregarious lifestyle. All cockroaches shared a broadly similar gut microbiota, with 66 microbial families present across all species and 13 present in every individual examined. Although our network analysis of the cockroach gut microbiome showed a large amount of connectivity, we demonstrated that gut microbiota cluster strongly by host species. We conducted follow-up tests to determine if cockroaches exhibit phylosymbiosis, or the tendency of host-associated microbial communities to parallel the phylogeny of related host species. Across the full data set, gut microbial community similarity was not found to correlate with host phylogenetic distance. However, a weak but significant phylosymbiotic signature was observed using the matching cluster metric, which allows for localized changes within a phylogenetic tree that are more likely to occur over long evolutionary distances. This finding suggests that host phylogeny plays a large role in structuring the cockroach gut microbiome over shorter evolutionary distances and a weak but significant role in shaping the gut microbiome over extended periods of evolutionary time. IMPORTANCE The gut microbiome plays a key role in host health. Therefore, it is important to understand the evolution of the gut microbiota and how it impacts, and is impacted by, host evolution. In this study, we explore the relationship between host phylogeny and gut microbiome composition in omnivorous, gregarious cockroaches within the Blattodea order, an ancient lineage that spans 300 million years of evolutionary divergence. We demonstrate a strong relationship between host species identity and gut microbiome composition and found a weaker but significant role for host phylogeny in determining microbiome similarity over extended periods of evolutionary time. This study advances our understanding of the role of host phylogeny in shaping the gut microbiome over different evolutionary distances.

Hostile Takeovers and Anti-takeover Defenses in the Russian Corporate Market

2007 ◽  
pp. 70-84 ◽  
Author(s):  
E. Demidova
Keyword(s):  
Cost Benefit Analysis ◽  
Cost Benefit ◽  
Benefit Analysis ◽  
Costs And Benefits ◽  
Hostile Takeovers ◽  
Russian Market ◽  
Takeover Defenses ◽  
The Cost ◽  
European Markets

This article analyzes definitions and the role of hostile takeovers at the Russian and European markets for corporate control. It develops the methodology of assessing the efficiency of anti-takeover defenses adapted to the conditions of the Russian market. The paper uses the cost-benefit analysis, where the costs and benefits of the pre-bid and post-bid defenses are compared.

The Evolutionary Psychology of Scientific Publishing: Cost-Benefit Optimization of Players in the Game

2019 ◽  
Author(s):  
Milind Watve
Keyword(s):  
Peer Review ◽  
Current System ◽  
Critical Mass ◽  
Cost Benefit ◽  
Active Role ◽  
Scientific Publishing ◽  
Collective Goal ◽  
The Cost ◽  
Collective Goals ◽  
Innate Tendency

Peer reviewed scientific publishing is critical for communicating important findings, interpretations and theories in any branch of science. While the value of peer review is rarely doubted, much concern is being raised about the possible biases in the process. I argue here that most of the biases originate in the evolved innate tendency of every player to optimize one’s own cost benefits. Different players in the scientific publishing game have different cost-benefit optima. There are multiple conflicts between individual optima and collective goals. An analysis of the cost-benefit optima of every player in the scientific publishing game shows how and why biases originate. In the current system of publishing, by optimization considerations, the probability of publishing a ‘bad’ manuscript is relatively small but the probability of rejecting a ‘good’ manuscript is very high. By continuing with the current publishing structure, the global distribution of the scientific community would be increasingly clustered. Publication biases by gender, ethnicity, reputation, conformation and conformity will be increasingly common and revolutionary concepts increasingly difficult to publish. Ultimately, I explore the possibility of designing a peer review publishing system in which the conflicts between individual optimization and collective goal can be minimized. In such a system, if everyone behaves with maximum selfishness, biases would be minimized and the progress towards the collective goal would be faster and smoother. Changing towards such a system might prove difficult unless a critical mass of authors take an active role to revolutionize scientific publishing.

What's it Worth? Improving Surface Water Quality

1999 ◽  
Vol 40 (10) ◽  
pp. 153-159 ◽  
Author(s):  
D. H. Newsome ◽  
C. D. Stephen
Keyword(s):  
Water Quality ◽  
Surface Water ◽  
Cost Benefit Analysis ◽  
Cost Benefit ◽  
Surface Water Quality ◽  
Control Measures ◽  
Benefit Analysis ◽  
The Cost

Many countries are investing in measures to improve surface water quality, but the investment programmes for so doing are increasingly becoming subject to cost-benefit analysis. Whilst the cost of control measures can usually be determined for individual improvement schemes, there are currently no established procedures for valuing the benefits attributable to improved surface water quality. The paper describes a methodology that has been derived that now makes this possible.

The Mismatch between Expectations and Realities of AS4 Audits: A Post-Implementation Research Analysis

2017 ◽  
Vol 37 (1) ◽  
pp. 1-19 ◽  
Author(s):  
Sanaz Aghazadeh ◽  
Marietta Peytcheva
Keyword(s):  
Implementation Research ◽  
Risk Premium ◽  
Cost Benefit ◽  
Multiple Methods ◽  
Material Weakness ◽  
Key Stakeholders ◽  
Auditing Standards ◽  
Equilibrium Market ◽  
The Cost ◽  
Research Analysis

SUMMARY We conduct a post-implementation research analysis of AS4, a standard guiding voluntary audits of material weakness (MW) remediation disclosures, to understand the reasons for the scarcity of AS4 audits in practice. We use multiple methods (experiments, comment letter analysis, and surveys) to understand the perspectives of key stakeholders. We find that regulators' expectations of the use of the standard did not come to fruition because an equilibrium market for active use of the standard could not be achieved; that managers desire to engage in AS4 audits for the riskier MWs but do not expect the associated costs to be high; and that auditors are reluctant to audit riskier MWs and would charge a considerable risk premium. Finally, we find that investors value AS4 audits, especially for riskier MWs, and find value in an AS4 audit for those risky MWs beyond that of the year-end audit. The overall findings of our study indicate that a mismatch in the cost-benefit functions of the key stakeholders led to a lack of AS4 audits. Our findings are important given the high costs associated with auditing standards development and approval.

scholarly journals Economic Analysis of the Use of VCS2000 for Pork Carcass Meat Yield Grading in Korea

Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1297
Author(s):  
Juntae Kim ◽  
Hyo-Dong Han ◽  
Wang Yeol Lee ◽  
Collins Wakholi ◽  
Jayoung Lee ◽  
...  
Keyword(s):  
Economic Analysis ◽  
Net Present Value ◽  
Cost Benefit Analysis ◽  
Cost Benefit ◽  
Feed Consumption ◽  
Cost Ratio ◽  
Benefit Analysis ◽  
Labor Costs ◽  
Meat Yield ◽  
The Cost

Currently, the pork industry is incorporating in-line automation with the aim of increasing the slaughtered pork carcass throughput while monitoring quality and safety. In Korea, 21 parameters (such as back-fat thickness and carcass weight) are used for quality grading of pork carcasses. Recently, the VCS2000 system—an automatic meat yield grading machine system—was introduced to enhance grading efficiency and therefore increase pork carcass production. The VCS2000 system is able to predict pork carcass yield based on image analysis. This study also conducted an economic analysis of the system using a cost—benefit analysis. The subsection items of the cost-benefit analysis considered were net present value (NPV), internal rate of return (IRR), and benefit/cost ratio (BC ratio), and each method was verified through sensitivity analysis. For our analysis, the benefits were grouped into three categories: the benefits of reducing labor costs, the benefits of improving meat yield production, and the benefits of reducing pig feed consumption through optimization. The cost-benefit analysis of the system resulted in an NPV of approximately 615.6 million Korean won, an IRR of 13.52%, and a B/C ratio of 1.65.

scholarly journals Cost-efficiency assessments of marine monitoring methods lack rigor—a systematic mapping of literature and an end-user view on optimal cost-efficiency analysis

2021 ◽  
Vol 193 (7) ◽  
Author(s):  
Heini Hyvärinen ◽  
Annaliina Skyttä ◽  
Susanna Jernberg ◽  
Kristian Meissner ◽  
Harri Kuosa ◽  
...  
Keyword(s):  
Comparative Studies ◽  
Cost Efficiency ◽  
Cost Benefit ◽  
Marine Ecosystems ◽  
Actual Cost ◽  
Monitoring Methods ◽  
Monitoring Method ◽  
Marine Monitoring ◽  
The Status ◽  
The Cost

AbstractGlobal deterioration of marine ecosystems, together with increasing pressure to use them, has created a demand for new, more efficient and cost-efficient monitoring tools that enable assessing changes in the status of marine ecosystems. However, demonstrating the cost-efficiency of a monitoring method is not straightforward as there are no generally applicable guidelines. Our study provides a systematic literature mapping of methods and criteria that have been proposed or used since the year 2000 to evaluate the cost-efficiency of marine monitoring methods. We aimed to investigate these methods but discovered that examples of actual cost-efficiency assessments in literature were rare, contradicting the prevalent use of the term “cost-efficiency.” We identified five different ways to compare the cost-efficiency of a marine monitoring method: (1) the cost–benefit ratio, (2) comparative studies based on an experiment, (3) comparative studies based on a literature review, (4) comparisons with other methods based on literature, and (5) subjective comparisons with other methods based on experience or intuition. Because of the observed high frequency of insufficient cost–benefit assessments, we strongly advise that more attention is paid to the coverage of both cost and efficiency parameters when evaluating the actual cost-efficiency of novel methods. Our results emphasize the need to improve the reliability and comparability of cost-efficiency assessments. We provide guidelines for future initiatives to develop a cost-efficiency assessment framework and suggestions for more unified cost-efficiency criteria.

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