scholarly journals Population level genetic differentiation among temperate Neoconocephalus katydids

2017 ◽  
Author(s):  
◽  
Gideon Ney

Recent work indicates that radiation events may play a significant role in shaping species diversity across entire continents. Here we quantify population level genetic differentiation in several species of Neoconocephalus katydids in order to determine the mechanisms of genetic isolation across a continental scale. Patterns of genetic isolation can be generalized into four types: isolation by resistance (IBR), isolation by barrier (IBB), isolation by distance (IBD), and epigenetic incompatibility. N. melanorhinus is a salt marsh specialist restricted to a narrow corridor along the Atlantic and Gulf coasts. IBD was the predominant pattern of variation across their range. In addition, we saw evidence of two possible biogeographic barriers to gene flow (IBB), one at the Atlantic-Gulf divide and the other along the Gulf coast. We investigated the impact of IBR by comparing genetic differentiation between a habitat specialist, N. bivocatus, and a habitat generalist, N. robustus. Similar levels of genetic diversity and genetic differentiation were present within populations of both species. Genetic variation and epigenetic changes can diverge between populations in isolation. We found significant variation in total methylation levels between N. bivocatus and N. robustus. Genetic differentiation did a better job of explaining species-specific phenotypes than epigenetic differentiation. Epigenetic differentiation, although present between species, is likely the result of an interaction between genetic and epigenetic loci.

2020 ◽  
Vol 105 (4) ◽  
pp. 481-501
Author(s):  
Itziar Arnelas ◽  
Ernesto Pérez-Collazos ◽  
Juan A. Devesa ◽  
Antonio J. Manzaneda ◽  
Pilar Catalan

The taxonomic boundaries of Centaurea L. species and infraspecific taxa are often blurred by hybridizations. However, counterbalancing genetic isolation contributes to maintaining taxonomic limits and fostering rapid speciation processes. Radiant (R) and non-radiant (NR) capitula are two major floral morphs present in Centaurea. However, it is unclear how gene flow affects the distribution of floral morphotypes across populations and taxa. We have investigated the taxonomic differentiation and potential effect of genetic isolation in R and NR populations of Iberian Centaurea sects. Jacea (Mill.) Pers. ex Dumort. and Lepteranthus (Neck. ex DC.) Dumort. A total of 510 individuals from 58 populations (12 taxa) were analyzed using 165 amplified fragment length polymorphism (AFLP) markers. Genetic diversity and structure parameters were estimated at the taxon, population, and floral morphotypic levels. We tested whether there was correlation between population pairwise fixation index (Fst) genetic distances and the inbreeding coefficient (Fis), taken as a surrogate of reproductive isolation between the R and NR morphotypes of each group, and also taking into account geographic distances, using distance-based redundancy analysis (dbRDA). We also performed isolation by distance (IBD) tests between different floral morphotypes, aiming to infer the impact of genetic isolation on evolutionary and taxonomic divergence of the individuals. The taxa of Centaurea sects. Jacea and Lepteranthus constitute independent evolutionary lineages. Most of the detected genetic clusters match the taxonomic circumscription proposed in our most recent treatments. Genetic diversity was highest in C. debeauxii Godr. & Gren. subsp. debeauxii and subsp. grandiflora (Gaudin ex Schübl. & G. Martens) Devesa & Arnelas and in C. jacea L. subsp. angustifolia (DC.) Gremli (R) and lowest in C. nevadensis Boiss. & Reut. (NR) within the Centaurea sect. Jacea clade, whereas it was highest in C. linifolia L. within the Centaurea sect. Lepteranthus clade. Population-level dbRDA tests did not detect a significant correlation of R versus NR genetic distances and Fis values in any of the studied cases; by contrast, they detected significant correlation with longitude (C. jacea subsp. angustifolia, C. debeauxii, C. linifolia–C. stuessyi Arnelas, Devesa & E. López) or latitude (C. nigra L.). IBD analysis at the individual level showed that, in addition to geography, other morphotype-related factors may affect the genetic differentiation of R versus NR morphs in C. nigra, C. debeauxii, and C. linifolia–C. stuessyi. These results suggest that the fixation of the different morphs within the same taxon or group may be explained by geographic isolation, though we could not discount other potential unknown factors that could have contributed to microspeciation in these recently divergent populations, which originated only several thousands of years ago.


2020 ◽  
Vol 12 (5) ◽  
pp. 701-714 ◽  
Author(s):  
Sarah E Bluher ◽  
Sara E Miller ◽  
Michael J Sheehan

Abstract Relatively little is known about the processes shaping population structure in cooperatively breeding insect species, despite the long-hypothesized importance of population structure in shaping patterns of cooperative breeding. Polistes paper wasps are primitively eusocial insects, with a cooperative breeding system in which females often found nests in cooperative associations. Prior mark-recapture studies of Polistes have documented extreme female philopatry, although genetic studies frequently fail to detect the strong population structure expected for highly philopatric species. Together these findings have led to lack of consensus on the degree of dispersal and population structure in these species. This study assessed population structure of female Polistes fuscatus wasps at three scales: within a single site, throughout Central New York, and across the Northeastern United States. Patterns of spatial genetic clustering and isolation by distance were observed in nuclear and mitochondrial genomes at the continental scale. Remarkably, population structure was evident even at fine spatial scales within a single collection site. However, P. fuscatus had low levels of genetic differentiation across long distances. These results suggest that P. fuscatus wasps may employ multiple dispersal strategies, including extreme natal philopatry as well as longer-distance dispersal. We observed greater genetic differentiation in mitochondrial genes than in the nuclear genome, indicative of increased dispersal distances in males. Our findings support the hypothesis that limited female dispersal contributes toward population structure in paper wasps.


2020 ◽  
Author(s):  
Lionel N. Di Santo ◽  
Jill A. Hamilton

AbstractMaintenance of biodiversity, through seed banks and botanical gardens where the wealth of species’ genetic variation may be preserved ex situ, is a major goal of conservation. However, challenges can persist in optimizing ex situ collections where trade-offs exist between expense, effort, and conserving species evolutionary potential, particularly when genetic data is not available. Within this context, we evaluate the genetic consequences of guiding population preservation using geographic (isolation-by-distance, IBD) and environmental (isolation-by-environment, IBE) data for ex situ collections where provenance data is available. We use 19 genetic and genomic datasets from 15 plant species to (i) assess the proportion of population genetic differentiation explained by geographic and environmental factors, and (ii) simulate ex situ collections prioritizing source populations based on pairwise geographic or environmental distances. Specifically, we test the impact prioritizing sampling based on environmental and geographic distances may have on capturing neutral, functional or putatively adaptive genetic diversity and differentiation. We find that collectively IBD and IBE explain a substantial proportion of genetic differences among functional (median 45%) and adaptive (median 71%) loci, but not for neutral loci (median 21.5%). Simulated ex situ collections reveal that inclusion of IBD and IBE increases both allelic diversity and genetic differentiation captured among populations, particularly for loci that may be important for adaptation. Thus, prioritizing population collections using environmental and geographic distance data can impact genetic variation captured ex situ. This provides value for the vast majority of plant species for which we have no genetic data, informing conservation of genetic variation needed to maintain evolutionary potential within collections.


Genes ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 637
Author(s):  
Heliodor Wierzbicki ◽  
Magdalena Zatoń-Dobrowolska ◽  
Anna Mucha ◽  
Magdalena Moska

In this study we assessed the level of genetic introgression between red foxes bred on fur farms in Poland and the native wild population. We also evaluated the impact of a geographic barrier and isolation by distance on gene flow between two isolated subpopulations of the native red fox and their genetic differentiation. Nuclear and mitochondrial DNA was collected from a total of 308 individuals (200 farm and 108 wild red foxes) to study non-native allele flow from farm into wild red fox populations. Genetic structure analyses performed using 24 autosomal microsatellites showed two genetic clusters as being the most probable number of distinct populations. No strong admixture signals between farm and wild red foxes were detected, and significant genetic differentiation was identified between the two groups. This was also apparent from the mtDNA analysis. None of the concatenated haplotypes detected in farm foxes was found in wild animals. The consequence of this was that the haplotype network displayed two genetically distinct groups: farm foxes were completely separated from native ones. Neither the River Vistula nor isolation by distance had a significant impact on gene flow between the separated wild red fox subpopulations. The results of our research indicate a low probability of genetic introgression between farm and native red foxes, and no threat to the genetic integrity of this species.


2009 ◽  
Vol 95 (1) ◽  
pp. 6-12
Author(s):  
Kusuma Madamala ◽  
Claudia R. Campbell ◽  
Edbert B. Hsu ◽  
Yu-Hsiang Hsieh ◽  
James James

ABSTRACT Introduction: On Aug. 29, 2005, Hurricane Katrina made landfall along the Gulf Coast of the United States, resulting in the evacuation of more than 1.5 million people, including nearly 6000 physicians. This article examines the relocation patterns of physicians following the storm, determines the impact that the disaster had on their lives and practices, and identifies lessons learned. Methods: An Internet-based survey was conducted among licensed physicians reporting addresses within Federal Emergency Management Agency-designated disaster zones in Louisiana and Mississippi. Descriptive data analysis was used to describe respondent characteristics. Multivariate logistic regression was performed to identify the factors associated with physician nonreturn to original practice. For those remaining relocated out of state, bivariate analysis with x2 or Fisher exact test was used to determine factors associated with plans to return to original practice. Results: A total of 312 eligible responses were collected. Among disaster zone respondents, 85.6 percent lived in Louisiana and 14.4 percent resided in Mississippi before the hurricane struck. By spring 2006, 75.6 percent (n = 236) of the respondents had returned to their original homes, whereas 24.4 percent (n = 76) remained displaced. Factors associated with nonreturn to original employment included family or general medicine practice (OR 0.42, 95 percent CI 0.17–1.04; P = .059) and severe or complete damage to the workplace (OR 0.24, 95 percent CI 0.13–0.42; P < .001). Conclusions: A sizeable proportion of physicians remain displaced after Hurricane Katrina, along with a lasting decrease in the number of physicians serving in the areas affected by the disaster. Programs designed to address identified physician needs in the aftermath of the storm may give confidence to displaced physicians to return.


2019 ◽  
Vol 80 (4) ◽  
pp. 200-204 ◽  
Author(s):  
Brittany Cormier ◽  
Lana Vanderlee ◽  
David Hammond

Purpose: In 2010, Health Canada implemented a national campaign to improve understanding of “percent daily value” (%DV) in Nutrition Facts Tables (NFTs). This study examined sources of nutrition information and knowledge of %DV information communicated in the campaign. Methods: Respondents aged 16–30 years completed the Canada Food Study in 2016 (n = 2665). Measures included sources of nutrition information, NFT use, and %DV knowledge based on the campaign message (“5% DV or less is a little; 15% DV or more is a lot”). A logistic regression examined correlates of providing “correct” responses to %DV questions related to the campaign messaging. Results: Overall, 7.2% (n = 191) respondents correctly indicated that 5% is “a little”, and 4.3% (n = 115) correctly indicated 15% DV was “a lot”. Only 4.0% (n = 107) correctly answered both. Correct recall of %DV amounts was not associated with number of information sources reported, but was greater among those who were female, were younger, and reported greater NFT understanding and serving size information use (P < 0.05 for all). Conclusions: Results show low awareness of messaging from the Nutrition Facts Education Campaign among young Canadians. Such a mass media campaign may be insufficient on its own to enhance population-level understanding of %DV.


BMJ Open ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. e043010
Author(s):  
Jane Lyons ◽  
Ashley Akbari ◽  
Fatemeh Torabi ◽  
Gareth I Davies ◽  
Laura North ◽  
...  

IntroductionThe emergence of the novel respiratory SARS-CoV-2 and subsequent COVID-19 pandemic have required rapid assimilation of population-level data to understand and control the spread of infection in the general and vulnerable populations. Rapid analyses are needed to inform policy development and target interventions to at-risk groups to prevent serious health outcomes. We aim to provide an accessible research platform to determine demographic, socioeconomic and clinical risk factors for infection, morbidity and mortality of COVID-19, to measure the impact of COVID-19 on healthcare utilisation and long-term health, and to enable the evaluation of natural experiments of policy interventions.Methods and analysisTwo privacy-protecting population-level cohorts have been created and derived from multisourced demographic and healthcare data. The C20 cohort consists of 3.2 million people in Wales on the 1 January 2020 with follow-up until 31 May 2020. The complete cohort dataset will be updated monthly with some individual datasets available daily. The C16 cohort consists of 3 million people in Wales on the 1 January 2016 with follow-up to 31 December 2019. C16 is designed as a counterfactual cohort to provide contextual comparative population data on disease, health service utilisation and mortality. Study outcomes will: (a) characterise the epidemiology of COVID-19, (b) assess socioeconomic and demographic influences on infection and outcomes, (c) measure the impact of COVID-19 on short -term and longer-term population outcomes and (d) undertake studies on the transmission and spatial spread of infection.Ethics and disseminationThe Secure Anonymised Information Linkage-independent Information Governance Review Panel has approved this study. The study findings will be presented to policy groups, public meetings, national and international conferences, and published in peer-reviewed journals.


Author(s):  
Kirti Sundar Sahu ◽  
Arlene Oetomo ◽  
Niloofar Jalali ◽  
Plinio P. Morita

The World Health Organization declared the coronavirus outbreak as a pandemic on March 11, 2020. To inhibit the spread of COVID-19, governments around the globe, including Canada, have implemented physical distancing and lockdown measures, including a work-from-home policy. Canada in 2020 has developed a 24-Hour Movement Guideline for all ages laying guidance on the ideal amount of physical activity, sedentary behaviour, and sleep (PASS) for an individual in a day. The purpose of this study was to investigate changes on the household and population-level in lifestyle behaviours (PASS) and time spent indoors at the household level, following the implementation of physical distancing protocols and stay-at-home guidelines. For this study, we used 2019 and 2020 data from ecobee, a Canadian smart Wi-Fi thermostat company, through the Donate Your Data (DYD) program. Using motion sensors data, we quantified the amount of sleep by using the absence of movement, and similarly, increased sensor activation to show a longer duration of household occupancy. The key findings of this study were; during the COVID-19 pandemic, overall household-level activity increased significantly compared to pre-pandemic times, there was no significant difference between household-level behaviours between weekdays and weekends during the pandemic, average sleep duration has not changed, but the pattern of sleep behaviour significantly changed, specifically, bedtime and wake up time delayed, indoor time spent has been increased and outdoor time significantly reduced. Our data analysis shows the feasibility of using big data to monitor the impact of the COVID-19 pandemic on the household and population-level behaviours and patterns of change.


ICL Journal ◽  
2020 ◽  
Vol 14 (2) ◽  
pp. 133-165
Author(s):  
Elisa Bertolini

AbstractThe article analyses the impact that the diminutive size of the four continental Europe micro states has upon their constitutional arrangements and their approach toward continental integration mechanisms. Generally speaking, the international commitment toward integration mechanisms is one of the distinguishing traits of micro states. It may seem a paradox, but actually the international dimension is much more strategic for micro than for macro states. However, being micro territorial enclaves demanded certain ability from the part of European micro states when managing foreign relations in order not to be swallowed by their macro neighbours. Therefore, they carried out for centuries a cautious policy of ‘guarded openness’, trying to strike a balance between the maintenance of their traditional institutions and the need to interact on a continental scale. Constitutional systems that at a first glance are unusual may be an obstacle to integration and thus have to be reformed. However, not too much, because otherwise the whole system may implode if deprived of its original constitutional balance. The protection of national tradition and identity is conservative, in the sense that it arises from the necessity of self-preservation, rather than from ideology. The article claims that the ambivalent approach of continental Europe micro states have when interacting with macro states within the Council of Europe and the EU directly derives from their diminutive size. Furthermore, the relevant role played by the diminutive size is proved by the fact that recently the EU adopted a specific micro states approach. Hence, the article also aims at investigating how they try to strike a balance between the commitment toward self-preservation – ie their constitutional identity – and the commitment toward continental integration mechanisms.


AMB Express ◽  
2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Neeraja Punde ◽  
Jennifer Kooken ◽  
Dagmar Leary ◽  
Patricia M. Legler ◽  
Evelina Angov

Abstract Codon usage frequency influences protein structure and function. The frequency with which codons are used potentially impacts primary, secondary and tertiary protein structure. Poor expression, loss of function, insolubility, or truncation can result from species-specific differences in codon usage. “Codon harmonization” more closely aligns native codon usage frequencies with those of the expression host particularly within putative inter-domain segments where slower rates of translation may play a role in protein folding. Heterologous expression of Plasmodium falciparum genes in Escherichia coli has been a challenge due to their AT-rich codon bias and the highly repetitive DNA sequences. Here, codon harmonization was applied to the malarial antigen, CelTOS (Cell-traversal protein for ookinetes and sporozoites). CelTOS is a highly conserved P. falciparum protein involved in cellular traversal through mosquito and vertebrate host cells. It reversibly refolds after thermal denaturation making it a desirable malarial vaccine candidate. Protein expressed in E. coli from a codon harmonized sequence of P. falciparum CelTOS (CH-PfCelTOS) was compared with protein expressed from the native codon sequence (N-PfCelTOS) to assess the impact of codon usage on protein expression levels, solubility, yield, stability, structural integrity, recognition with CelTOS-specific mAbs and immunogenicity in mice. While the translated proteins were expected to be identical, the translated products produced from the codon-harmonized sequence differed in helical content and showed a smaller distribution of polypeptides in mass spectra indicating lower heterogeneity of the codon harmonized version and fewer amino acid misincorporations. Substitutions of hydrophobic-to-hydrophobic amino acid were observed more commonly than any other. CH-PfCelTOS induced significantly higher antibody levels compared with N-PfCelTOS; however, no significant differences in either IFN-γ or IL-4 cellular responses were detected between the two antigens.


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