Mutation load dynamics during environmentally-driven range shifts

AbstractThe fitness of spatially expanding species has been shown to decrease over time and space, but specialist species tracking their changing environment and shifting their range accordingly have been little studied. We use individual-based simulations and analytical modeling to compare the impact of range expansions and range shifts on genetic diversity and fitness loss, as well as the ability to recover fitness after either a shift or expansion. We find that the speed of a shift has a strong impact on fitness evolution. Fastest shifts show the strongest fitness loss per generation, but intermediate shift speeds lead to the strongest fitness loss per geographic distance. Range shifting species lose fitness more slowly through time than expanding species, however, their fitness compared at equivalent geographic distances spread can be considerably lower. These counter-intuitive results arise from the combination of time over which selection acts and mutations enter the system. Range shifts also exhibit reduced fitness recovery after a geographic shift and may result in extinction, whereas range expansions can persist from the core of the species range. The complexity of range expansions and range shifts highlights the potential for severe consequences of environmental change on species survival.Author SummaryAs environments change through time across the globe, species must adapt or relocate to survive. Specialized species must track the specific moving environments to which they are adapted, as compared to generalists which can spread widely. During colonization of new habitat, individuals can accumulate deleterious alleles through repeated bottlenecks. We show through simulation and analytic modeling that the process by which these alleles accumulate changes depending upon the speed at which populations spread over a landscape. This is due to the increased efficacy of selection against deleterious variants at slow speeds of range shifts and decreased input of mutations at faster speeds of range shifts. Under some selective circumstances, shifting of a species range leads to extinction of the entire population. This suggests that the rate of environmental change across the globe will play a large role in the survival of specialist species as compared to more generalist species.

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Climate Connectivity of European Forests for Species Range Shifts

Forests ◽

10.3390/f12070940 ◽

2021 ◽

Vol 12 (7) ◽

pp. 940

Author(s):

Qiyao Han ◽

Greg Keeffe ◽

Sean Cullen

Keyword(s):

Emission Scenario ◽

Species Range ◽

Range Shifts ◽

Forest Patch ◽

Climate Conditions ◽

European Forests ◽

Forest Connectivity ◽

Forested Area ◽

High Conservation ◽

The Impact

Forest connectivity is important for the range shifts and long-term persistence of forest-dependent species, especially in the context of climate change. This study assessed the climate connectivity of European forests for species to track suitable climate conditions as the climate warms. Here, climate connectivity was calculated as the temperature difference between each forest patch and the coolest patch that can be reached along temperature gradients. We found that, overall, about 36% of the total forested area in Europe has achieved successful climate connectivity under the moderate emission scenario (SSP245), whereby species range shifts could circumvent the impact of climate warming. The percentage is much lower under the highest emission scenario (SSP585), which is only 12%. To identify forest areas of high importance for climate connectivity, we further evaluated the potential of each forest patch to serve as a stepping stone for species range shifts. Our results showed that about 94% of the European forested area is expected to experience species range shifts. Our study identified sites of high conservation value for improving and sustaining forest connectivity to facilitate climate-driven range shifts and thus could provide information for climate-smart management of European forests.

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Species’ range dynamics affect the evolution of spatial variation in plasticity under environmental change

10.1101/344895 ◽

2018 ◽

Author(s):

Max Schmid ◽

Ramon Dallo ◽

Frédéric Guillaume

Keyword(s):

Phenotypic Plasticity ◽

Environmental Change ◽

Range Expansion ◽

Evolutionary Dynamics ◽

Environmental Changes ◽

Species Range ◽

Range Shifts ◽

Environmental Tolerance ◽

Spatial Differences ◽

Range Dynamics

AbstractWhile clines in environmental tolerance and phenotypic plasticity along a single species’ range are widespread and of special interest in the context of adaptation to environmental changes, we know little about their evolution. Recent empirical findings in ectotherms suggest that processes underlying dynamic species’ ranges can give rise to spatial differences in environmental tolerance and phenotypic plasticity within species. We used individual-based simulations to investigate how plasticity and tolerance evolve in the course of three scenarios of species’ range shifts and range expansions on environmental gradients. We found that regions of a species’ range which experienced a longer history or larger extent of environmental change generally exhibited increased plasticity or tolerance. Such regions may be at the trailing edge when a species is tracking its ecological niche in space (e.g., in a climate change scenario) or at the front edge when a species expands into a new habitat (e.g., in an expansion/invasion scenario). Elevated tolerance and plasticity in the distribution center was detected when asymmetric environmental change (e.g., polar amplification) led to a range expansion. Greater gene flow across the range had a dual effect on plasticity and tolerance clines, with an amplifying effect in niche expansion scenarios (allowing for faster colonization into novel environments), but with a dampening effect in range shift scenarios (favoring spatial translocation of adapted genotypes). However, tolerance and plasticity clines were transient and slowly flattened out after range dynamics because of genetic assimilation. In general, our approach allowed us to investigate the evolution of environmental tolerance and phenotypic plasticity under transient evolutionary dynamics in non-equilibrium situations, which contributes to a better understanding of observed patterns and of how species may respond to future environmental changes.Impact SummaryIn a variable and changing environment, the ability of a species to cope with a range of selection pressures and a multitude of environmental conditions is critical, both for its’ spatial distribution and its’ long-term persistence. Striking examples of spatial differences in environmental tolerance have been found within species, when single populations differed from each other in their environmental optimum and tolerance breadth, a characteristic that might strongly modify a species’ response to future environmental change. However, we still know little about the evolutionary processes causing these tolerance differences between populations, especially when the differences result from transient evolutionary dynamics in non-equilibrium situations. We demonstrate with individual-based simulations, how spatial differences in environmental tolerance and phenotypic plasticity evolved across a species’ range during three scenarios of range shifts and range expansion. Range dynamics were either driven by environmental change or by the expansion of the ecological niche. The outcome strongly differed between scenarios as tolerance and plasticity were maximized either at the leading edge, at the trailing edge, or in the middle of the species’ range. Spatial tolerance variation resulted from colonization chronologies and histories of environmental change that varied along the range. Subsequent to the range dynamics, the tolerance and plasticity clines slowly leveled out again as result of genetic assimilation such that the described responses are long-lasting, but in the end temporary. These findings help us better understand species’ evolutionary responses during range shifts and range expansion, especially when facing environmental change.

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When Do Psychopathic Traits Affect Cooperative Behavior?: An Iterated Prisoner's Dilemma Experimental Study

10.26686/wgtn.12431003 ◽

2020 ◽

Author(s):

M Testori ◽

M Kempf ◽

RB Hoyle ◽

Hedwig Eisenbarth

Keyword(s):

Prisoner's Dilemma ◽

Cooperative Behavior ◽

Prisoner’S Dilemma ◽

Selection Procedure ◽

Psychopathic Traits ◽

Strong Impact ◽

Iterated Prisoner's Dilemma ◽

Human Decision ◽

The Impact ◽

Iterated Prisoner’S Dilemma

© 2019 Hogrefe Publishing. Personality traits have been long recognized to have a strong impact on human decision-making. In this study, a sample of 314 participants took part in an online game to investigate the impact of psychopathic traits on cooperative behavior in an iterated Prisoner's dilemma game. We found that disinhibition decreased the maintenance of cooperation in successive plays, but had no effect on moving toward cooperation after a previous defection or on the overall level of cooperation over rounds. Furthermore, our results underline the crucial importance of a good model selection procedure, showing how a poor choice of statistical model can provide misleading results.

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The Impact of Economic Crisis on Tourism Industry: A Bangladesh Perspective

International Research Journal of Engineering IT & Scientific Research ◽

10.21744/irjeis.v2i1.35 ◽

2016 ◽

Vol 2 (1) ◽

Author(s):

Md. Ziaul Haque

Keyword(s):

Economic Crisis ◽

Tourism Industry ◽

Political Crisis ◽

Strong Impact ◽

Negative Consequences ◽

Policy Makers ◽

Tourism Product ◽

International Tourist ◽

Sustained Recovery ◽

The Impact

The tourism sector is experiencing numerous challenges as a result of the global economic crisis. After a significant contraction in 2009, tourism rebounded strongly in 2010 and in 2011 the international tourist arrivals and receipts are projected to increase substantially. The Tourism industry is expected to show a sustained recovery in 2012. The crisis has particularly strong impact and slightly negative consequences in Bangladesh. The country is undergoing a political crisis, as well, and it seems that the forthcoming elections may be the only solution for the restoration of stability and social peace. In addition, tourism can be the driving force behind Bangladesh economic recovery. However, for its achievement the country’s policy makers should take several measures towards restructuring and improving the sector. These measures include: enhancement of alternative forms of tourism; environmental protection; creation of quality infrastructure; and boost of competitiveness through a tourism product that offers value for money

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The Impact Of Economic Crisis On Tourism Industry: A Bangladesh Perspective

International Research Journal of Engineering IT & Scientific Research ◽

10.21744/irjeis.v1i1.29 ◽

2015 ◽

Vol 1 (1) ◽

pp. 15

Author(s):

Md. Ziaul Haque

Keyword(s):

Economic Crisis ◽

Tourism Industry ◽

Political Crisis ◽

Strong Impact ◽

Negative Consequences ◽

Policy Makers ◽

Tourism Product ◽

International Tourist ◽

Sustained Recovery ◽

The Impact

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Cost of Dementia and Its Correlation With Dependence

Journal of Aging and Health ◽

10.1177/0898264315624899 ◽

2016 ◽

Vol 28 (8) ◽

pp. 1448-1464 ◽

Cited By ~ 17

Author(s):

Örjan Åkerborg ◽

Andrea Lang ◽

Anders Wimo ◽

Anders Sköldunger ◽

Laura Fratiglioni ◽

...

Keyword(s):

Cognitive Ability ◽

Resource Utilization ◽

Annual Cost ◽

Neuropsychiatric Symptoms ◽

Dementia Care ◽

Cost Of Care ◽

Path Model ◽

National Study ◽

Strong Impact ◽

The Impact

Objective: To estimate the cost of dementia care and its relation to dependence. Method: Disease severity and health care resource utilization was retrieved from the Swedish National Study on Aging and Care. Informal care was assessed with the Resource Utilization in Dementia instrument. A path model investigates the relationship between annual cost of care and dependence, cognitive ability, functioning, neuropsychiatric symptoms, and comorbidities. Results: Average annual cost among patients diagnosed with dementia was €43,259, primarily incurred by accommodation. Resource use, that is, institutional care, community care, and accommodation, and corresponding costs increased significantly by increasing dependency. Path analysis showed that cognitive ability, functioning, and neuropsychiatric symptoms were significantly correlated with dependence, which in turn had a strong impact on annual cost. Discussion: This study confirms that cost of dementia care increases with dependence and that the impact of other disease indicators is mainly mediated by dependence.

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Anomalous Laterally Stressed Kinetically Trapped DNA Surface Conformations

Nano-Micro Letters ◽

10.1007/s40820-021-00626-2 ◽

2021 ◽

Vol 13 (1) ◽

Author(s):

Valery V. Prokhorov ◽

Nikolay A. Barinov ◽

Kirill A. Prusakov ◽

Evgeniy V. Dubrovin ◽

Maxim D. Frank-Kamenetskii ◽

...

Keyword(s):

Electrostatic Interaction ◽

Mechanical Response ◽

Persistence Length ◽

Strong Impact ◽

List Type ◽

Surface Charges ◽

Monomolecular Films ◽

Chain Approximation ◽

The Impact ◽

Positively Charged

Highlights DNA kinking is inevitable for the highly anisotropic 1D–1D electrostatic interaction with the one-dimensionally periodically charged surface. The double helical structure of the DNA kinetically trapped on positively charged monomolecular films comprising the lamellar templates is strongly laterally stressed and extremely perturbed at the nanometer scale. The DNA kinetic trapping is not a smooth 3D—> 2D conformational flattening but is a complex nonlinear in-plane mechanical response (bending, tensile and unzipping) driven by the physics beyond the scope of the applicability of the linear worm-like chain approximation. Abstract Up to now, the DNA molecule adsorbed on a surface was believed to always preserve its native structure. This belief implies a negligible contribution of lateral surface forces during and after DNA adsorption although their impact has never been elucidated. High-resolution atomic force microscopy was used to observe that stiff DNA molecules kinetically trapped on monomolecular films comprising one-dimensional periodically charged lamellar templates as a single layer or as a sublayer are oversaturated by sharp discontinuous kinks and can also be locally melted and supercoiled. We argue that kink/anti-kink pairs are induced by an overcritical lateral bending stress (> 30 pNnm) inevitable for the highly anisotropic 1D-1D electrostatic interaction of DNA and underlying rows of positive surface charges. In addition, the unexpected kink-inducing mechanical instability in the shape of the template-directed DNA confined between the positively charged lamellar sides is observed indicating the strong impact of helicity. The previously reported anomalously low values of the persistence length of the surface-adsorbed DNA are explained by the impact of the surface-induced low-scale bending. The sites of the local melting and supercoiling are convincingly introduced as other lateral stress-induced structural DNA anomalies by establishing a link with DNA high-force mechanics. The results open up the study in the completely unexplored area of the principally anomalous kinetically trapped DNA surface conformations in which the DNA local mechanical response to the surface-induced spatially modulated lateral electrostatic stress is essentially nonlinear. The underlying rich and complex in-plane nonlinear physics acts at the nanoscale beyond the scope of applicability of the worm-like chain approximation.

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War of words: the impact of Russian state television on the Russian Internet

Nationalities Papers ◽

10.1080/00905992.2015.1013527 ◽

2015 ◽

Vol 43 (4) ◽

pp. 533-555 ◽

Cited By ~ 22

Author(s):

Christina Cottiero ◽

Katherine Kucharski ◽

Evgenia Olimpieva ◽

Robert W. Orttung

Keyword(s):

World War Ii ◽

Quantitative Data ◽

The Internet ◽

Strong Impact ◽

World War ◽

Search Query ◽

Internet Users ◽

Russian State ◽

The Impact ◽

The Relationship

How effective is Russian state television in framing the conflict in Ukraine that began with the Euromaidan protests and what is its impact on Russian Internet users? We carried out a content analysis of Dmitrii Kiselev's “News of the Week” show, which allowed us to identify the two key frames he used to explain the conflict – World War II-era fascism and anti-Americanism. Since Kiselev often reduces these frames to buzzwords, we were able to track the impact of these words on Internet users by examining search query histories on Yandex and Google and by developing quantitative data to complement our qualitative analysis. Our findings show that much of what state media produces is not effective, but that the “fascist” and anti-American frames have had lasting impacts on Russian Internet users. We argue that it does not make sense to speak of competition between a “television party” and an “Internet party” in Russia since state television has a strong impact in setting the agenda for the Internet and society as a whole. Ultimately, the relationship between television and the Internet in Russia is a continual loop, with each affecting the other.

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