Geographical gradients in selection can reveal genetic constraints for evolutionary responses to ocean acidification

Geographical gradients in selection can shape different genetic architectures in natural populations, reflecting potential genetic constraints for adaptive evolution under climate change. Investigation of natural pH/ p CO 2 variation in upwelling regions reveals different spatio-temporal patterns of natural selection, generating genetic and phenotypic clines in populations, and potentially leading to local adaptation, relevant to understanding effects of ocean acidification (OA). Strong directional selection, associated with intense and continuous upwellings, may have depleted genetic variation in populations within these upwelling regions, favouring increased tolerances to low pH but with an associated cost in other traits. In contrast, diversifying or weak directional selection in populations with seasonal upwellings or outside major upwelling regions may have resulted in higher genetic variances and the lack of genetic correlations among traits. Testing this hypothesis in geographical regions with similar environmental conditions to those predicted under climate change will build insights into how selection may act in the future and how populations may respond to stressors such as OA.

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Predicting Adaptive Genetic Variation of Loblolly Pine (Pinus taeda L.) Populations Under Projected Future Climates Based on Multivariate Models

Journal of Heredity ◽

10.1093/jhered/esz065 ◽

2019 ◽

Vol 110 (7) ◽

pp. 857-865 ◽

Cited By ~ 3

Author(s):

Mengmeng Lu ◽

Konstantin V Krutovsky ◽

Carol A Loopstra

Keyword(s):

Climate Change ◽

South Carolina ◽

Genetic Variation ◽

Loblolly Pine ◽

Greenhouse Gas Emission ◽

Isolation By Distance ◽

Adaptive Genetic Variation ◽

Climate Conditions ◽

Geographical Regions ◽

Bioclimatic Variables

Abstract Greenhouse gas emission and global warming are likely to cause rapid climate change within the natural range of loblolly pine over the next few decades, thus bringing uncertainty to their adaptation to the environment. Here, we studied adaptive genetic variation of loblolly pine and correlated genetic variation with bioclimatic variables using multivariate modeling methods—Redundancy Analysis, Generalized Dissimilarity Modeling, and Gradient Forests. Studied trees (N = 299) were originally sampled from their native range across eight states on the east side of the Mississippi River. Genetic variation was calculated using a total of 44,317 single-nucleotide polymorphisms acquired by exome target sequencing. The fitted models were used to predict the adaptive genetic variation on a large spatial and temporal scale. We observed east-to-west spatial genetic variation across the range, which presented evidence of isolation by distance. Different key factors drive adaptation of loblolly pine from different geographical regions. Trees residing near the northeastern edge of the range, spanning across Delaware and Maryland and mountainous areas of Virginia, North Carolina, South Carolina, and northern Georgia, were identified to be most likely impacted by climate change based on the large difference in genetic composition under current and future climate conditions. This study provides new perspectives on adaptive genetic variation of loblolly pine in response to different climate scenarios, and the results can be used to target particular populations while developing adaptive forest management guidelines.

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Cryptic genetic variation underpins rapid adaptation to ocean acidification

10.1101/700526 ◽

2019 ◽

Cited By ~ 2

Author(s):

M. C. Bitter ◽

L. Kapsenberg ◽

J.-P. Gattuso ◽

C. A. Pfister

Keyword(s):

Climate Change ◽

Genetic Variation ◽

Natural Populations ◽

Future Climate Change ◽

Rapid Adaptation ◽

Larval Size ◽

Larval Population ◽

Cryptic Genetic Variation ◽

Standing Variation ◽

Seawater Ph

AbstractGlobal climate change has intensified the need to assess the capacity for natural populations to adapt to abrupt shifts in the environment. Reductions in seawater pH constitute a conspicuous stressor associated with increasing atmospheric carbon dioxide that is affecting ecosystems throughout the world’s oceans. Here, we quantify the phenotypic and genetic modifications associated with rapid adaptation to reduced seawater pH in the marine mussel, Mytilus galloprovincialis. We reared a genetically diverse larval population in ambient and extreme low pH conditions (pHT 8.1 and 7.4) and tracked changes in the larval size and allele frequency distributions through settlement. Additionally, we separated larvae by size to link a fitness-related trait to its underlying genetic background in each treatment. Both phenotypic and genetic data show that M. galloprovincialis can evolve in response to a decrease in seawater pH. This process is polygenic and characterized by genotype-environment interactions, suggesting the role of cryptic genetic variation in adaptation to future climate change. Holistically, this work provides insight into the processes underpinning rapid evolution, and demonstrates the importance of maintaining standing variation within natural populations to bolster species’ adaptive capacity as global change progresses.

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Genomic analysis of European Drosophila melanogaster populations reveals longitudinal structure, continent-wide selection, and previously unknown DNA viruses

10.1101/313759 ◽

2018 ◽

Cited By ~ 12

Author(s):

Martin Kapun ◽

Maite G. Barrón ◽

Fabian Staubach ◽

Darren J. Obbard ◽

R. Axel W. Wiberg ◽

...

Keyword(s):

Drosophila Melanogaster ◽

Genetic Variation ◽

Climate Adaptation ◽

Natural Populations ◽

Genomic Analysis ◽

Short Term ◽

Dna Viruses ◽

Local Climate ◽

Term Evolution ◽

Spatio Temporal

AbstractGenetic variation is the fuel of evolution, with standing genetic variation especially important for short-term evolution and local adaptation. To date, studies of spatio-temporal patterns of genetic variation in natural populations have been challenging, as comprehensive sampling is logistically difficult, and sequencing of entire populations costly. Here, we address these issues using a collaborative approach, sequencing 48 pooled population samples from 32 locations, and perform the first continent-wide genomic analysis of genetic variation in European Drosophila melanogaster. Our analyses uncover longitudinal population structure, provide evidence for continent-wide selective sweeps, identify candidate genes for local climate adaptation, and document clines in chromosomal inversion and transposable element frequencies. We also characterise variation among populations in the composition of the fly microbiome, and identify five new DNA viruses in our samples.

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Plasticity in novel environments induces larger changes in genetic variance than adaptive divergence

10.1101/2021.02.08.430333 ◽

2021 ◽

Author(s):

Greg M. Walter ◽

Delia Terranova ◽

James Clark ◽

Salvatore Cozzolino ◽

Antonia Cristaudo ◽

...

Keyword(s):

Genetic Variation ◽

Phenotypic Plasticity ◽

Quantitative Genetics ◽

Leaf Morphology ◽

Genetic Variance ◽

Genetic Correlations ◽

Elevational Gradient ◽

Adaptive Divergence ◽

Genetic Constraints ◽

Novel Environments

AbstractGenetic correlations between traits are expected to constrain the rate of adaptation by concentrating genetic variation in certain phenotypic directions, which are unlikely to align with the direction of selection in novel environments. However, if genotypes vary in their response to novel environments, then plasticity could create changes in genetic variation that will determine whether genetic constraints to adaptation arise. We tested this hypothesis by mating two species of closely related, but ecologically distinct, Sicilian daisies (Senecio, Asteraceae) using a quantitative genetics breeding design. We planted seeds of both species across an elevational gradient that included the native habitat of each species and two intermediate elevations, and measured eight leaf morphology and physiology traits on established seedlings. We detected large significant changes in genetic variance across elevation and between species. Elevational changes in genetic variance within species were greater than differences between the two species. Furthermore, changes in genetic variation across elevation aligned with phenotypic plasticity. These results suggest that to understand adaptation to novel environments we need to consider how genetic variance changes in response to environmental variation, and the effect of such changes on genetic constraints to adaptation and the evolution of plasticity.

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Erfassung der adaptiven genetischen Variation der Eiche im Hinblick auf den Klimawandel | Assessment of adaptive genetic variation in oaks with relation to climate change

Schweizerische Zeitschrift fur Forstwesen ◽

10.3188/szf.2010.0216 ◽

2010 ◽

Vol 161 (6) ◽

pp. 216-222

Author(s):

Oliver Gailing

Keyword(s):

Climate Change ◽

Genetic Variation ◽

North America ◽

Phenotypic Variation ◽

Natural Populations ◽

Genetic Adaptation ◽

Adaptive Genetic Variation ◽

Adaptation To Climate Change ◽

Adaptive Traits ◽

Wide Range

Climate change is projected to lead to a major reorganization of our forests. For example, higher annual mean temperatures, longer growth seasons and drier summers are predicted for many parts of central and southern Europe, and in North America. In order to understand the genetic adaptation to climate change we need a better understanding of the genetic regulation of key traits involved in tolerance of water and temperature stress. Oaks (Quercus spp.) are excellent model species to study the adaptation of forest trees to changing environments. They show a wide geographic distribution in Europe and in North America as dominant tree species in many forests growing under a wide range of climatic and edaphic conditions. With the availability of a growing amount of functional and expressional candidate genes we are now able to test the functional importance of genes by associating nucleotide variation in these genes with phenotypic variation in adaptive traits in segregating or natural populations. Studies trying to associate genetic variation with phenotypic variation in adaptive traits can be performed in full-sib families derived from controlled crosses (Quantitative Trait Loci [QTL] mapping) or in natural populations (association mapping). For several important adaptive traits QTL were mapped, the underlying genes have to be tested in natural populations. A future objective is to test whether genes that underlie phenotypic variation in adaptive traits are involved in local genetic adaptation and viability selection at the seedling stage, linked to reciprocal transplant experiments in order to assess the performance over climatic gradients.

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The evolutionary potential of diet-dependent effects on lifespan and fecundity in a multi-parental population of Drosophila melanogaster

10.1101/343947 ◽

2018 ◽

Cited By ~ 2

Author(s):

Enoch Ng’oma ◽

Wilton Fidelis ◽

Kevin M. Middleton ◽

Elizabeth G. King

Keyword(s):

Drosophila Melanogaster ◽

Genetic Variation ◽

Genetic Correlations ◽

Natural Populations ◽

Evolutionary Potential ◽

Fitness Components ◽

Nutrient Imbalance ◽

Quantitative Genetic ◽

Nutritional Conditions ◽

Quantitative Genetic Parameters

AbstractThe nutritional conditions experienced by a population play a major role in shaping trait evolution in many taxa. Constraints exerted by nutrient limitation or nutrient imbalance can influence the maximal value that fitness components such as reproduction and lifespan attains, and organisms may shift how resources are allocated to different structures and functions in response to changes in nutrition. Whether the phenotypic changes associated with changes in nutrition represent an adaptive response is largely unknown. Further, it is unclear whether the response of fitness components to diet even has the potential to evolve in most systems. In this study, we use an admixed multiparental population of Drosophila melanogaster reared in three different diet conditions to estimate quantitative genetic parameters for lifespan and fecundity. We find significant genetic variation for both traits in our population and show that lifespan has moderate to high heritabilities within diets. Genetic correlations for lifespan between diets were significantly less than one, demonstrating a strong genotype by diet interaction. These findings demonstrate substantial standing genetic variation in our population that is comparable to natural populations and highlights the potential for adaptation to changing nutritional environments.

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Quantitative genetic basis of floral design in a natural plant population

10.1101/2020.11.06.371831 ◽

2020 ◽

Author(s):

Juannan Zhou ◽

Charles B. Fenste ◽

Richard J. Reynolds

Keyword(s):

Genetic Variation ◽

Genetic Parameters ◽

Mixed Model ◽

Linear Mixed Model ◽

Genetic Correlations ◽

Natural Populations ◽

Plant Evolution ◽

Floral Traits ◽

Floral Trait ◽

Evolutionary Trajectory

AbstractThe amount of genetic variation of floral traits and the degree to which they are genetically correlated are important parameters for the study of plant evolution. Estimates of these parameters can reveal the effect of historical selection relative to neutral processes such as mutation and drift, and allow us to predict the short-term evolutionary trajectory of a population under various selective regimes. Here, we assess the heritability and genetic correlation of the floral design of a native N. American tetraploid plant, Silene stellata (Caryophyllaceae), in a natural population. Specifically, we use a linear mixed model to estimate the genetic parameters based on a genealogy reconstructed from highly variable molecular markers. Overall, we found significant heritabilities in five out of nine studied traits. The level of heritability was intermediate (0.027 – 0.441). Interestingly, the floral trait showing the highest level of genetic variation was previously shown to be under strong sexually conflicting selection, which may serve as a mechanism for maintaining the observed genetic variation. Additionally, we also found prevalent positive genetic correlations between floral traits. Our results suggest that S. stellata is capable of responding to phenotypic selection on its floral design, while the abundant positive genetic correlations could also constrain the evolutionary trajectories to certain directions. Furthermore, this study demonstrates the utility and feasibility of marker-based approaches for estimating genetic parameters in natural populations.

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Projected impacts of climate change and ocean acidification on the global biogeography of planktonic Foraminifera

Biogeosciences ◽

10.5194/bg-12-2873-2015 ◽

2015 ◽

Vol 12 (10) ◽

pp. 2873-2889 ◽

Cited By ~ 12

Author(s):

T. Roy ◽

F. Lombard ◽

L. Bopp ◽

M. Gehlen

Keyword(s):

Climate Change ◽

Ocean Acidification ◽

Large Scale ◽

Planktonic Foraminifera ◽

Marine Carbonate ◽

Geographical Regions ◽

Calcite Saturation ◽

Abundance And Diversity ◽

The Tropics ◽

Carbonate Flux

Abstract. Planktonic Foraminifera are a major contributor to the deep carbonate flux and their microfossil deposits form one of the richest databases for reconstructing paleoenvironments, particularly through changes in their taxonomic and shell composition. Using an empirically based planktonic foraminifer model that incorporates three known major physiological drivers of their biogeography – temperature, food and light – we investigate (i) the global redistribution of planktonic Foraminifera under anthropogenic climate change and (ii) the alteration of the carbonate chemistry of foraminiferal habitat with ocean acidification. The present-day and future (2090–2100) 3-D distributions of Foraminifera are simulated using temperature, plankton biomass and light from an Earth system model forced with a historical and a future (IPCC A2) high CO2 emission scenario. Foraminiferal abundance and diversity are projected to decrease in the tropics and subpolar regions and increase in the subtropics and around the poles. Temperature is the dominant control on the future change in the biogeography of Foraminifera. Yet food availability acts to either reinforce or counteract the temperature-driven changes. In the tropics and subtropics the largely temperature-driven shift to depth is enhanced by the increased concentration of phytoplankton at depth. In the higher latitudes the food-driven response partly offsets the temperature-driven reduction both in the subsurface and across large geographical regions. The large-scale rearrangements in foraminiferal abundance and the reduction in the carbonate ion concentrations in the habitat range of planktonic foraminifers – from 10–30 μmol kg−1 in their polar and subpolar habitats to 30–70 μmol kg−1 in their subtropical and tropical habitats – would be expected to lead to changes in the marine carbonate flux. High-latitude species are most vulnerable to anthropogenic change: their abundance and available habitat decrease and up to 10% of the volume of their habitat drops below the calcite saturation horizon.

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Genotype by environment interactions for the shade avoidance syndrome in the plant Antirrhinum majus, the snapdragon

10.1101/331033 ◽

2018 ◽

Author(s):

Mathilde Mousset ◽

Sara Marin ◽

Juliette Archambeau ◽

Christel Blot ◽

Vincent Bonhomme ◽

...

Keyword(s):

Genetic Variation ◽

Natural Populations ◽

Common Garden ◽

Antirrhinum Majus ◽

Shade Avoidance ◽

Response To Selection ◽

Plastic Response ◽

Genetic Constraints ◽

Shade Avoidance Syndrome ◽

Evolutionary Response

AbstractA classical example of phenotypic plasticity in plants is the set of trait changes in response to shade, i.e. the shade avoidance syndrome. There is widespread evidence that plants in low light conditions often avoid shade by growing taller or by increasing their photosynthetic efficiency. This plastic response is expected to have evolved in response to selection in several species, yet there is limited evidence for its genetic variation within populations, which is required for any evolutionary response to selection. In this study, we investigated the shade avoidance syndrome in snapdragon plants (Antirrhinum majus) by using a common garden approach on four natural populations from the Mediterranean region. Our results showed that, in the four populations, individual plants reacted strongly to the presence of shade by growing longer shoots, longer internodes, and increasing their specific leaf area. Our results also revealed genetic variation for the plastic response within these populations, as well as few genetic constraints to its evolution. Our findings imply that the plastic response to shade has the potential to evolve in response to selection in natural populations of A. majus.

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The genetic architecture of sexual dimorphism in the mossCeratodon purpureus

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2020.2908 ◽

2021 ◽

Vol 288 (1946) ◽

pp. 20202908

Author(s):

Leslie M. Kollar ◽

Scott Kiel ◽

Ashley J. James ◽

Cody T. Carnley ◽

Danielle N. Scola ◽

...

Keyword(s):

Sexual Dimorphism ◽

Evolutionary Biology ◽

Genetic Architecture ◽

Genetic Correlations ◽

Natural Populations ◽

Sexual Antagonism ◽

Antagonistic Selection ◽

Genetic Constraints ◽

Sexually Antagonistic Selection ◽

The Cross

A central problem in evolutionary biology is to identify the forces that maintain genetic variation for fitness in natural populations. Sexual antagonism, in which selection favours different variants in males and females, can slow the transit of a polymorphism through a population or can actively maintain fitness variation. The amount of sexually antagonistic variation to be expected depends in part on the genetic architecture of sexual dimorphism, about which we know relatively little. Here, we used a multivariate quantitative genetic approach to examine the genetic architecture of sexual dimorphism in a scent-based fertilization syndrome of the mossCeratodon purpureus.We found sexual dimorphism in numerous traits, consistent with a history of sexually antagonistic selection. The cross-sex genetic correlations (rmf) were generally heterogeneous with many values indistinguishable from zero, which typically suggests that genetic constraints do not limit the response to sexually antagonistic selection. However, we detected no differentiation between the female- and male-specific trait (co)variance matrices (GfandGm, respectively), meaning the evolution of sexual dimorphism may be constrained. The cross-sex cross-trait covariance matrixBcontained both symmetric and asymmetric elements, indicating that the response to sexually antagonistic or sexually concordant selection, and the constraint to sexual dimorphism, are highly dependent on the traits experiencing selection. The patterns of genetic variances and covariances among these fitness components is consistent with partly sex-specific genetic architectures having evolved in order to partially resolve multivariate genetic constraints (i.e. sexual conflict), enabling the sexes to evolve towards their sex-specific multivariate trait optima.

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