1
|
Barton N. Limits to species' range: the tension between local and global adaptation. J Evol Biol 2024; 37:605-615. [PMID: 38683160 DOI: 10.1093/jeb/voae052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Revised: 04/02/2024] [Accepted: 05/08/2024] [Indexed: 05/01/2024]
Abstract
We know that heritable variation is abundant, and that selection causes all but the smallest populations to rapidly shift beyond their original trait distribution. So then, what limits the range of a species? There are physical constraints and also population genetic limits to the effectiveness of selection, ultimately set by population size. Global adaptation, where the same genotype is favoured over the whole range, is most efficient when based on a multitude of weakly selected alleles and is effective even when local demes are small, provided that there is some gene flow. In contrast, local adaptation is sensitive to gene flow and may require alleles with substantial effect. How can populations combine the advantages of large effective size with the ability to specialise into local niches? To what extent does reproductive isolation help resolve this tension? I address these questions using eco-evolutionary models of polygenic adaptation, contrasting discrete demes with continuousspace.
Collapse
Affiliation(s)
- Nicholas Barton
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| |
Collapse
|
2
|
Prakash A, Capblancq T, Shallows K, Saville D, Landau D, Landress C, Jacobs T, Keller S. Bringing genomics to the field: An integrative approach to seed sourcing for forest restoration. APPLICATIONS IN PLANT SCIENCES 2024; 12:e11600. [PMID: 38912128 PMCID: PMC11192164 DOI: 10.1002/aps3.11600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 04/15/2024] [Accepted: 04/16/2024] [Indexed: 06/25/2024]
Abstract
Premise Global anthropogenic change threatens the health and productivity of forest ecosystems. Assisted migration and reforestation are tools to help mitigate these impacts. However, questions remain about how to approach sourcing seeds to ensure high establishment and future adaptability. Methods Using exome-capture sequencing, we demonstrate a computational approach to finding the best n-sets from a candidate list of seed sources that collectively achieve high genetic diversity (GD) and minimal genetic load (GL), while also increasing evolvability in quantitative traits. The benefits of this three-part strategy (diversity-load-evolvability) are to increase near-term establishment success while also boosting evolutionary potential to respond to future stressors. Members of The Nature Conservancy and the Central Appalachian Spruce Restoration Initiative planted 58,000 seedlings across 255 acres. A subset of seedlings was monitored for establishment success and variation in growth. Results The results show gains in GD relative to GL and increases in quantitative genetic variation in seedling growth for pooled vs. single-source restoration. No single "super source" was observed across planting sites; rather, monitoring results demonstrate that pooling of multiple sources helps achieve higher GD:GL and evolvability. Discussion Our study shows the potential for integrating genomics into local-scale restoration and the importance of building partnerships between academic researchers and applied conservation managers.
Collapse
Affiliation(s)
- Anoob Prakash
- Department of Plant BiologyUniversity of VermontBurlingtonVermontUSA
| | - Thibaut Capblancq
- Department of Plant BiologyUniversity of VermontBurlingtonVermontUSA
- Laboratoire d'Écologie Alpine, Université Grenoble‐Alpes, Université Savoie Mont Blanc, CNRSGrenobleFrance
| | - Kathryn Shallows
- Central Appalachians Program, The Nature ConservancyElkinsWest VirginiaUSA
| | - David Saville
- Appalachian Forest Restoration LLCMorgantownWest VirginiaUSA
| | - Deborah Landau
- Maryland/DC Chapter, The Nature ConservancyBethesdaMarylandUSA
| | - Chad Landress
- USDA Forest Service, Monongahela National ForestElkinsWest VirginiaUSA
| | - Tal Jacobs
- Clinch Valley Program, The Nature ConservancyAbingdonVirginiaUSA
| | - Stephen Keller
- Department of Plant BiologyUniversity of VermontBurlingtonVermontUSA
| |
Collapse
|
3
|
Chaikin S, Riva F, Marshall KE, Lessard JP, Belmaker J. Marine fishes experiencing high-velocity range shifts may not be climate change winners. Nat Ecol Evol 2024; 8:936-946. [PMID: 38459374 DOI: 10.1038/s41559-024-02350-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 01/28/2024] [Indexed: 03/10/2024]
Abstract
Climate change is driving the global redistribution of species. A common assumption is that rapid range shifts occur in tandem with overall stable or positive abundance trends throughout the range and thus these species may be considered as climate change 'winners'. However, although establishing the link between range shift velocities and population trends is crucial for predicting climate change impacts it has not been empirically tested. Using 2,572 estimates of changes in marine fish abundance spread across the world's oceans, we show that poleward range shifts are not necessarily associated with positive population trends. Species experiencing high-velocity range shifts seem to experience local population declines irrespective of the position throughout the species range. High range shift velocities of 17 km yr-1 are associated with a 50% decrease in population sizes over a period of 10 yr, which is dramatic compared to the overall stable population trends in non-shifting species. This pattern, however, mostly occurs in populations located in the poleward, colder, portion of the species range. The lack of a positive association between poleward range shift velocities and population trends at the coldest portion of the range contrasts with the view that rapid range shifts safeguard against local population declines. Instead, our work suggests that marine fishes experiencing rapid range shifts could be more vulnerable to climatic change and therefore should be carefully assessed for conservation status.
Collapse
Affiliation(s)
- Shahar Chaikin
- School of Zoology, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel.
| | - Federico Riva
- Department of Environmental Geography, Institute for Environmental Studies (IVM), Vrije Universiteit Amsterdam, Amsterdam, the Netherlands
| | - Katie E Marshall
- Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada
| | | | - Jonathan Belmaker
- School of Zoology, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
- The Steinhardt Museum of Natural History, Tel Aviv University, Tel-Aviv, Israel
| |
Collapse
|
4
|
Urquhart-Cronish M, Angert AL, Otto SP, MacPherson A. Density-Dependent Selection during Range Expansion Affects Expansion Load in Life History Traits. Am Nat 2024; 203:382-392. [PMID: 38358811 DOI: 10.1086/728599] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2024]
Abstract
AbstractModels of range expansion have independently explored fitness consequences of life history trait evolution and increased rates of genetic drift-or "allele surfing"-during spatial spread, but no previous model has examined the interactions between these two processes. Here, using spatially explicit simulations, we explore an ecologically complex range expansion scenario that combines density-dependent selection with allele surfing to asses the genetic and fitness consequences of density-dependent selection on the evolution of life history traits. We demonstrate that density-dependent selection on the range edge acts differently depending on the life history trait and can either diminish or enhance allele surfing. Specifically, we show that selection at the range edge is always weaker at sites affecting competitive ability (K-selected traits) than at sites affecting birth rate (r-selected traits). We then link differences in the frequency of deleterious mutations to differences in the efficacy of selection and rate of mutation accumulation across distinct life history traits. Finally, we demonstrate that the observed fitness consequences of allele surfing depend on the population density in which expansion load is measured. Our work highlights the complex relationship between ecology and expressed genetic load, which will be important to consider when interpreting both experimental and field studies of range expansion.
Collapse
|
5
|
Huang S, Feigs JT, Holzhauer SIJ, Kramp K, Brunet J, Decocq G, De Frenne P, Diekmann M, Liira J, Spicher F, Vangansbeke P, Vanneste T, Verheyen K, Naaf T. Limited effects of population age on the genetic structure of spatially isolated forest herb populations in temperate Europe. Ecol Evol 2024; 14:e10971. [PMID: 38414568 PMCID: PMC10897356 DOI: 10.1002/ece3.10971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 12/06/2023] [Accepted: 01/30/2024] [Indexed: 02/29/2024] Open
Abstract
Due to multiple land-cover changes, forest herb populations residing in forest patches embedded in agricultural landscapes display different ages and, thus, experience differences in genetic exchange, mutation accumulation and genetic drift. The extent of divergence in present-day population genetic structure among these populations of different ages remains unclear, considering their diverse breeding systems and associated pollinators. Answering this question is essential to understand these species' persistence, maintenance of evolutionary potential and adaptability to changing environments. We applied a multi-landscape setup to compare the genetic structure of forest herb populations across forest patches of different ages (18-338 years). We studied the impact on three common slow-colonizer herb species with distinct breeding systems and associated pollinators: Polygonatum multiflorum (outcrossing, long-distance pollinators), Anemone nemorosa (outcrossing, short-distance pollinators) and Oxalis acetosella (mixed breeding). We aimed to assess if in general older populations displayed higher genetic diversity and lower differentiation than younger ones. We also anticipated that P. multiflorum would show the smallest while O. acetosella the largest difference, between old and young populations. We found that older populations had a higher observed heterozygosity (H o) but a similar level of allelic richness (A r) and expected heterozygosity (H e) as younger populations, except for A. nemorosa, which exhibited higher A r and H e in younger populations. As populations aged, their pairwise genetic differentiation measured by D PS decreased independent of species identity while the other two genetic differentiation measures showed either comparable levels between old and young populations (G" ST) or inconsistency among three species (cGD). The age difference of the two populations did not explain their genetic differentiation. Synthesis: We found restricted evidence that forest herb populations with different ages differ in their genetic structure, indicating that populations of different ages can reach a similar genetic structure within decades and thus persist in the long term after habitat disturbance. Despite their distinct breeding systems and associated pollinators, the three studied species exhibited partly similar genetic patterns, suggesting that their common characteristics, such as being slow colonizers or their ability to propagate vegetatively, are important in determining their long-term response to land-cover change.
Collapse
Affiliation(s)
- Siyu Huang
- Leibniz Centre for Agricultural Landscape Research (ZALF)MünchebergGermany
| | - Jannis Till Feigs
- Leibniz Centre for Agricultural Landscape Research (ZALF)MünchebergGermany
| | | | - Katja Kramp
- Leibniz Centre for Agricultural Landscape Research (ZALF)MünchebergGermany
| | - Jörg Brunet
- Southern Swedish Forest Research CentreSwedish University of Agricultural SciencesLommaSweden
| | - Guillaume Decocq
- Research Unit Ecology and Dynamics of Anthropized SystemsUniversity of Picardie Jules VerneAmiens CedexFrance
| | - Pieter De Frenne
- Forest & Nature Lab, Department of EnvironmentGhent UniversityGontrodeBelgium
| | - Martin Diekmann
- Vegetation Ecology and Conservation Biology, Institute of Ecology, FB 2University of BremenBremenGermany
| | - Jaan Liira
- Institute of Ecology and Earth ScienceUniversity of TartuTartuEstonia
| | - Fabien Spicher
- Research Unit Ecology and Dynamics of Anthropized SystemsUniversity of Picardie Jules VerneAmiens CedexFrance
| | - Pieter Vangansbeke
- Forest & Nature Lab, Department of EnvironmentGhent UniversityGontrodeBelgium
| | - Thomas Vanneste
- Forest & Nature Lab, Department of EnvironmentGhent UniversityGontrodeBelgium
| | - Kris Verheyen
- Forest & Nature Lab, Department of EnvironmentGhent UniversityGontrodeBelgium
| | - Tobias Naaf
- Leibniz Centre for Agricultural Landscape Research (ZALF)MünchebergGermany
| |
Collapse
|
6
|
Cang FA, Welles SR, Wong J, Ziaee M, Dlugosch KM. Genome size variation and evolution during invasive range expansion in an introduced plant. Evol Appl 2024; 17:e13624. [PMID: 38283607 PMCID: PMC10810172 DOI: 10.1111/eva.13624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 11/03/2023] [Accepted: 11/13/2023] [Indexed: 01/30/2024] Open
Abstract
Plants demonstrate exceptional variation in genome size across species, and their genome sizes can also vary dramatically across individuals and populations within species. This aspect of genetic variation can have consequences for traits and fitness, but few studies attributed genome size differentiation to ecological and evolutionary processes. Biological invasions present particularly useful natural laboratories to infer selective agents that might drive genome size shifts across environments and population histories. Here, we test hypotheses for the evolutionary causes of genome size variation across 14 invading populations of yellow starthistle, Centaurea solstitialis, in California, United States. We use a survey of genome sizes and trait variation to ask: (1) Is variation in genome size associated with developmental trait variation? (2) Are genome sizes smaller toward the leading edge of the expansion, consistent with selection for "colonizer" traits? Or alternatively, does genome size increase toward the leading edge of the expansion, consistent with predicted consequences of founder effects and drift? (3) Finally, are genome sizes smaller at higher elevations, consistent with selection for shorter development times? We found that 2C DNA content varied 1.21-fold among all samples, and was associated with flowering time variation, such that plants with larger genomes reproduced later, with lower lifetime capitula production. Genome sizes increased toward the leading edge of the invasion, but tended to decrease at higher elevations, consistent with genetic drift during range expansion but potentially strong selection for smaller genomes and faster development time at higher elevations. These results demonstrate how genome size variation can contribute to traits directly tied to reproductive success, and how selection and drift can shape that variation. We highlight the influence of genome size on dynamics underlying a rapid range expansion in a highly problematic invasive plant.
Collapse
Affiliation(s)
- F. Alice Cang
- Department of Ecology and Evolutionary BiologyUniversity of ArizonaTucsonArizonaUSA
| | - Shana R. Welles
- Department of Ecology and Evolutionary BiologyUniversity of ArizonaTucsonArizonaUSA
- Utah Valley UniversityOremUtahUSA
| | - Jenny Wong
- Department of Ecology and Evolutionary BiologyUniversity of ArizonaTucsonArizonaUSA
| | - Maia Ziaee
- Department of Ecology and Evolutionary BiologyUniversity of ArizonaTucsonArizonaUSA
- Mills CollegeOaklandCaliforniaUSA
| | - Katrina M. Dlugosch
- Department of Ecology and Evolutionary BiologyUniversity of ArizonaTucsonArizonaUSA
| |
Collapse
|
7
|
Aihara T, Araki K, Onuma Y, Cai Y, Paing AMM, Goto S, Hisamoto Y, Tomaru N, Homma K, Takagi M, Yoshida T, Iio A, Nagamatsu D, Kobayashi H, Hirota M, Uchiyama K, Tsumura Y. Divergent mechanisms of reduced growth performance in Betula ermanii saplings from high-altitude and low-latitude range edges. Heredity (Edinb) 2023; 131:387-397. [PMID: 37940658 PMCID: PMC10673911 DOI: 10.1038/s41437-023-00655-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 10/13/2023] [Accepted: 10/13/2023] [Indexed: 11/10/2023] Open
Abstract
The reduced growth performance of individuals from range edges is a common phenomenon in various taxa, and considered to be an evolutionary factor that limits the species' range. However, most studies did not distinguish between two mechanisms that can lead to this reduction: genetic load and adaptive selection to harsh conditions. To address this lack of understanding, we investigated the climatic and genetic factors underlying the growth performance of Betula ermanii saplings transplanted from 11 populations including high-altitude edge and low-latitude edge population. We estimated the climatic position of the populations within the overall B. ermanii's distribution, and the genetic composition and diversity using restriction-site associated DNA sequencing, and measured survival, growth rates and individual size of the saplings. The high-altitude edge population (APW) was located below the 95% significance interval for the mean annual temperature range, but did not show any distinctive genetic characteristics. In contrast, the low-latitude edge population (SHK) exhibited a high level of linkage disequilibrium, low genetic diversity, a distinct genetic composition from the other populations, and a high relatedness coefficient. Both APW and SHK saplings displayed lower survival rates, heights and diameters, while SHK saplings also exhibited lower growth rates than the other populations' saplings. The low heights and diameters of APW saplings was likely the result of adaptive selection to harsh conditions, while the low survival and growth rates of SHK saplings was likely the result of genetic load. Our findings shed light on the mechanisms underlying the reduced growth performance of range-edge populations.
Collapse
Affiliation(s)
- Takaki Aihara
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, Ibaraki, 305-8577, Japan
| | - Kyoko Araki
- Garden Division, Maintenance and Works Department, the Imperial Household Agency, 1-1, Chiyoda, Chiyoda-ku, Tokyo, 100-8111, Japan
- Graduate School of Science and Technology, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, Ibaraki, 305-8577, Japan
| | - Yunosuke Onuma
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, Ibaraki, 305-8577, Japan
| | - Yihan Cai
- Graduate School of Environmental Science, Hokkaido University, Kita 10 Nishi 5, Kita-ku, Sapporo, 060-0810, Japan
| | - Aye Myat Myat Paing
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1, Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan
| | - Susumu Goto
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1, Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan
| | - Yoko Hisamoto
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1, Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan
| | - Nobuhiro Tomaru
- Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Cikusa-ku, Nagoya, Aichi, 464-0804, Japan
| | - Kosuke Homma
- Sado Island Center for Ecological Sustainability, Niigata University, 1101-1, Niibokatagami, Sado, Niigata, 952-0103, Japan
| | - Masahiro Takagi
- Faculty of Agriculture, University of Miyazaki, 1-1, Gakuen kibanadai nishi, Miyazaki, Miyazaki, 889-2192, Japan
| | - Toshiya Yoshida
- Field Science Center for Northern Biosphere, Hokkaido University, Kita 10 Nishi 5, Kita-ku, Sapporo, 060-0810, Japan
| | - Atsuhiro Iio
- Graduate School of Integrated Science and Technology, Shizuoka University, 836, Ohtani, Suruga-ku, Shizuoka, Shizuoka, 422-8017, Japan
| | - Dai Nagamatsu
- Faculty of Agriculture, Tottori University, 4-101, Koyama-cho, Tottori, Tottori, 680-8553, Japan
| | - Hajime Kobayashi
- Faculty of Agriculture, Shinshu University, 8304, Minamiminowa-mura, Kamiina-gun, Nagano, 399-4598, Japan
| | - Mitsuru Hirota
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, Ibaraki, 305-8577, Japan
| | - Kentaro Uchiyama
- Department of Forest Molecular Genetics and Biotechnology, Forestry and Forest Products Research Institute, 1, Matsunosato, Tsukuba, Ibaraki, 305-8687, Japan
| | - Yoshihiko Tsumura
- Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1, Tennodai, Tsukuba, Ibaraki, 305-8577, Japan.
| |
Collapse
|
8
|
Kim AS, Kreiner JM, Hernández F, Bock DG, Hodgins KA, Rieseberg LH. Temporal collections to study invasion biology. Mol Ecol 2023; 32:6729-6742. [PMID: 37873879 DOI: 10.1111/mec.17176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 10/07/2023] [Accepted: 10/11/2023] [Indexed: 10/25/2023]
Abstract
Biological invasions represent an extraordinary opportunity to study evolution. This is because accidental or deliberate species introductions have taken place for centuries across large geographical scales, frequently prompting rapid evolutionary transitions in invasive populations. Until recently, however, the utility of invasions as evolutionary experiments has been hampered by limited information on the makeup of populations that were part of earlier invasion stages. Now, developments in ancient and historical DNA technologies, as well as the quickening pace of digitization for millions of specimens that are housed in herbaria and museums globally, promise to help overcome this obstacle. In this review, we first introduce the types of temporal data that can be used to study invasions, highlighting the timescale captured by each approach and their respective limitations. We then discuss how ancient and historical specimens as well as data available from prior invasion studies can be used to answer questions on mechanisms of (mal)adaptation, rates of evolution, or community-level changes during invasions. By bridging the gap between contemporary and historical invasive populations, temporal data can help us connect pattern to process in invasion science. These data will become increasingly important if invasions are to achieve their full potential as experiments of evolution in nature.
Collapse
Affiliation(s)
- Amy S Kim
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Julia M Kreiner
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Fernando Hernández
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Dan G Bock
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kathryn A Hodgins
- School of Biological Sciences, Monash University, Melbourne, Victoria, Australia
| | - Loren H Rieseberg
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| |
Collapse
|
9
|
James J, Kastally C, Budde KB, González-Martínez SC, Milesi P, Pyhäjärvi T, Lascoux M. Between but Not Within-Species Variation in the Distribution of Fitness Effects. Mol Biol Evol 2023; 40:msad228. [PMID: 37832225 PMCID: PMC10630145 DOI: 10.1093/molbev/msad228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 09/04/2023] [Accepted: 09/25/2023] [Indexed: 10/15/2023] Open
Abstract
New mutations provide the raw material for evolution and adaptation. The distribution of fitness effects (DFE) describes the spectrum of effects of new mutations that can occur along a genome, and is, therefore, of vital interest in evolutionary biology. Recent work has uncovered striking similarities in the DFE between closely related species, prompting us to ask whether there is variation in the DFE among populations of the same species, or among species with different degrees of divergence, that is whether there is variation in the DFE at different levels of evolution. Using exome capture data from six tree species sampled across Europe we characterized the DFE for multiple species, and for each species, multiple populations, and investigated the factors potentially influencing the DFE, such as demography, population divergence, and genetic background. We find statistical support for the presence of variation in the DFE at the species level, even among relatively closely related species. However, we find very little difference at the population level, suggesting that differences in the DFE are primarily driven by deep features of species biology, and those evolutionarily recent events, such as demographic changes and local adaptation, have little impact.
Collapse
Affiliation(s)
- Jennifer James
- Department of Ecology and Genetics, Uppsala University, Uppsala, Sweden
- Swedish Collegium of Advanced Study, Uppsala University, Uppsala, Sweden
| | - Chedly Kastally
- Department of Forest Sciences, University of Helsinki, Helsinki, Finland
- Viikki Plant Science Centre, University of Helsinki, Helsinki, Finland
| | - Katharina B Budde
- Department of Forest Genetics and Forest Tree Breeding, Georg-August-University Goettingen, Goettingen, Germany
- Center of Biodiversity and Sustainable Land Use (CBL), University of Goettingen, Goettingen, Germany
| | - Santiago C González-Martínez
- National Research Institute for Agriculture, Food and the Environment (INRAE), University of Bordeaux, BIOGECO, Cestas, France
| | - Pascal Milesi
- Department of Ecology and Genetics, Uppsala University, Uppsala, Sweden
- Science for Life Laboratory (SciLifeLab), Uppsala University, Uppsala, Sweden
| | - Tanja Pyhäjärvi
- Department of Forest Sciences, University of Helsinki, Helsinki, Finland
- Viikki Plant Science Centre, University of Helsinki, Helsinki, Finland
| | - Martin Lascoux
- Department of Ecology and Genetics, Uppsala University, Uppsala, Sweden
| |
Collapse
|
10
|
Rougemont Q, Leroy T, Rondeau EB, Koop B, Bernatchez L. Allele surfing causes maladaptation in a Pacific salmon of conservation concern. PLoS Genet 2023; 19:e1010918. [PMID: 37683018 PMCID: PMC10545117 DOI: 10.1371/journal.pgen.1010918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 10/02/2023] [Accepted: 08/11/2023] [Indexed: 09/10/2023] Open
Abstract
How various factors, including demography, recombination or genome duplication, may impact the efficacy of natural selection and the burden of deleterious mutations, is a central question in evolutionary biology and genetics. In this study, we show that key evolutionary processes, including variations in i) effective population size (Ne) ii) recombination rates and iii) chromosome inheritance, have influenced the genetic load and efficacy of selection in Coho salmon (Oncorhynchus kisutch), a widely distributed salmonid species on the west coast of North America. Using whole genome resequencing data from 14 populations at different migratory distances from their southern glacial refugium, we found evidence supporting gene surfing, wherein reduced Ne at the postglacial recolonization front, leads to a decrease in the efficacy of selection and a surf of deleterious alleles in the northernmost populations. Furthermore, our results indicate that recombination rates play a prime role in shaping the load along the genome. Additionally, we identified variation in polyploidy as a contributing factor to within-genome variation of the load. Overall, our results align remarkably well with expectations under the nearly neutral theory of molecular evolution. We discuss the fundamental and applied implications of these findings for evolutionary and conservation genomics.
Collapse
Affiliation(s)
- Quentin Rougemont
- Centre d’Ecologie Fonctionnelle et Evolutive, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France
| | - Thibault Leroy
- GenPhySE, INRAE, INP, ENVT, Université de Toulouse, Auzeville- Tolosane, France
| | - Eric B. Rondeau
- Department of Fisheries and Ocean, Pacific Biological Station, Nanaimo, Canada
| | - Ben Koop
- Department of Biology, University of Victoria, Victoria, Canada
| | - Louis Bernatchez
- Département de Biologie, Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Canada
| |
Collapse
|
11
|
Zeitler L, Parisod C, Gilbert KJ. Purging due to self-fertilization does not prevent accumulation of expansion load. PLoS Genet 2023; 19:e1010883. [PMID: 37656747 PMCID: PMC10501686 DOI: 10.1371/journal.pgen.1010883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 09/14/2023] [Accepted: 07/25/2023] [Indexed: 09/03/2023] Open
Abstract
As species expand their geographic ranges, colonizing populations face novel ecological conditions, such as new environments and limited mates, and suffer from evolutionary consequences of demographic change through bottlenecks and mutation load accumulation. Self-fertilization is often observed at species range edges and, in addition to countering the lack of mates, is hypothesized as an evolutionary advantage against load accumulation through increased homozygosity and purging. We study how selfing impacts the accumulation of genetic load during range expansion via purging and/or speed of colonization. Using simulations, we disentangle inbreeding effects due to demography versus due to selfing and find that selfers expand faster, but still accumulate load, regardless of mating system. The severity of variants contributing to this load, however, differs across mating system: higher selfing rates purge large-effect recessive variants leaving a burden of smaller-effect alleles. We compare these predictions to the mixed-mating plant Arabis alpina, using whole-genome sequences from refugial outcrossing populations versus expanded selfing populations. Empirical results indicate accumulation of expansion load along with evidence of purging in selfing populations, concordant with our simulations, suggesting that while purging is a benefit of selfing evolving during range expansions, it is not sufficient to prevent load accumulation due to range expansion.
Collapse
Affiliation(s)
- Leo Zeitler
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | - Christian Parisod
- Department of Biology, University of Fribourg, Fribourg, Switzerland
| | | |
Collapse
|
12
|
Cisternas-Fuentes A, Koski MH. Drivers of strong isolation and small effective population size at a leading range edge of a widespread plant. Heredity (Edinb) 2023:10.1038/s41437-023-00610-z. [PMID: 37016137 DOI: 10.1038/s41437-023-00610-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 03/09/2023] [Accepted: 03/09/2023] [Indexed: 04/06/2023] Open
Abstract
Climate change has influenced species distributions worldwide with upward elevational shifts observed in many systems. Leading range edge populations, like those at upper elevation limits, are crucial for climate change responses but can exhibit low genetic diversity due to founder effects, isolation, or limited outbreeding. These factors can hamper local adaptation at range limits. Using the widespread herb, Argentina anserina, we measured ecological attributes (population density on the landscape, area of population occupancy, and plant and flower density) spanning a 1000 m elevation gradient, with high elevation populations at the range limit. We measured vegetative clonal potential in the greenhouse for populations spanning the gradient. We combined these data with a ddRAD-seq dataset to test the hypotheses that high elevation populations would exhibit ecological and genomic signatures of leading range edge populations. We found that population density on the landscape declined towards the high elevation limit, as is expected towards range edges. However, plant density was elevated within edge populations. In the greenhouse, high elevation plants exhibited stronger clonal potential than low elevation plants, likely explaining increased plant density in the field. Phylogeographic analysis supported more recent colonization of high elevation populations which were also more genetically isolated, had more extreme heterozygote excess and had smaller effective population size than low. Results support that colonization of high elevations was likely accompanied by increased asexuality, contributing to a decline in effective population size. Despite high plant density in leading edge populations, their small effective size, isolation and clonality could constrain adaptive potential.
Collapse
Affiliation(s)
- Anita Cisternas-Fuentes
- Department of Biological Sciences, Clemson University, 132 Long Hall, Clemson, SC, 29634, USA.
| | - Matthew H Koski
- Department of Biological Sciences, Clemson University, 132 Long Hall, Clemson, SC, 29634, USA.
| |
Collapse
|
13
|
Robinson J, Kyriazis CC, Yuan SC, Lohmueller KE. Deleterious Variation in Natural Populations and Implications for Conservation Genetics. Annu Rev Anim Biosci 2023; 11:93-114. [PMID: 36332644 PMCID: PMC9933137 DOI: 10.1146/annurev-animal-080522-093311] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Deleterious mutations decrease reproductive fitness and are ubiquitous in genomes. Given that many organisms face ongoing threats of extinction, there is interest in elucidating the impact of deleterious variation on extinction risk and optimizing management strategies accounting for such mutations. Quantifying deleterious variation and understanding the effects of population history on deleterious variation are complex endeavors because we do not know the strength of selection acting on each mutation. Further, the effect of demographic history on deleterious mutations depends on the strength of selection against the mutation and the degree of dominance. Here we clarify how deleterious variation can be quantified and studied in natural populations. We then discuss how different demographic factors, such as small population size, nonequilibrium population size changes, inbreeding, and gene flow, affect deleterious variation. Lastly, we provide guidance on studying deleterious variation in nonmodel populations of conservation concern.
Collapse
Affiliation(s)
- Jacqueline Robinson
- Institute for Human Genetics, University of California, San Francisco, California, USA;
| | - Christopher C Kyriazis
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, California, USA; , ,
| | - Stella C Yuan
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, California, USA; , ,
| | - Kirk E Lohmueller
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, California, USA; , , .,Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, California, USA
| |
Collapse
|
14
|
Moreira LR, Klicka J, Smith BT. Demography and linked selection interact to shape the genomic landscape of codistributed woodpeckers during the Ice Age. Mol Ecol 2023; 32:1739-1759. [PMID: 36617622 DOI: 10.1111/mec.16841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 12/13/2022] [Accepted: 12/20/2022] [Indexed: 01/10/2023]
Abstract
The influence of genetic drift on population dynamics during Pleistocene glacial cycles is well understood, but the role of selection in shaping patterns of genomic variation during these events is less explored. We resequenced whole genomes to investigate how demography and natural selection interact to generate the genomic landscapes of Downy and Hairy Woodpecker, species codistributed in previously glaciated North America. First, we explored the spatial and temporal patterns of genomic diversity produced by neutral evolution. Next, we tested (i) whether levels of nucleotide diversity along the genome are correlated with intrinsic genomic properties, such as recombination rate and gene density, and (ii) whether different demographic trajectories impacted the efficacy of selection. Our results revealed cycles of bottleneck and expansion, and genetic structure associated with glacial refugia. Nucleotide diversity varied widely along the genome, but this variation was highly correlated between the species, suggesting the presence of conserved genomic features. In both taxa, nucleotide diversity was positively correlated with recombination rate and negatively correlated with gene density, suggesting that linked selection played a role in reducing diversity. Despite strong fluctuations in effective population size, the maintenance of relatively large populations during glaciations may have facilitated selection. Under these conditions, we found evidence that the individual demographic trajectory of populations modulated linked selection, with purifying selection being more efficient in removing deleterious alleles in large populations. These results highlight that while genome-wide variation reflects the expected signature of demographic change during climatic perturbations, the interaction of multiple processes produces a predictable and highly heterogeneous genomic landscape.
Collapse
Affiliation(s)
- Lucas R Moreira
- Department of Ecology, Evolution, and Environmental Biology, Columbia University, New York, New York, USA.,Department of Ornithology, American Museum of Natural History, New York City, New York, USA.,Program in Bioinformatics and Integrative Biology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
| | - John Klicka
- Burke Museum of Natural History and Culture and Department of Biology, University of Washington, Seattle, Washington, USA
| | - Brian Tilston Smith
- Department of Ornithology, American Museum of Natural History, New York City, New York, USA
| |
Collapse
|
15
|
Perrier A, Willi Y. Intraspecific variation in reproductive barriers between two closely related Arabidopsis sister species. J Evol Biol 2023; 36:121-130. [PMID: 36436201 PMCID: PMC10100320 DOI: 10.1111/jeb.14122] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 09/07/2022] [Accepted: 09/25/2022] [Indexed: 11/29/2022]
Abstract
Reproductive isolation (RI) is a critical component of speciation and varies strongly in timing and strength among different sister taxa, depending on, for example the geography of speciation and divergence time. However, these factors may also produce variation in timing and strength among populations within species. Here we tested for variation in the expression of RI among replicate population pairs between the sister taxa Arabidopsis lyrata subsp. lyrata and A. arenicola. While the former is predominantly outcrossing, the latter is predominantly selfing. We focused on intrinsic prezygotic and postzygotic RI as both species occur largely in allopatry. We assessed RI by performing within-population crosses and interspecific between-population crosses, and by raising offspring. RI was generally high between all interspecific population pairs, but it varied in timing and strength depending on population history. Prezygotic isolation was strongest between the closest-related population pair, while early postzygotic isolation was high for all other population pairs. Furthermore, the timing and strength of RI depended strongly on cross direction. Our study provides empirical support that reproductive barriers between species are highly variable among population pairs and asymmetric within population pairs, and this variation seems to follow patterns typically described across species pairs.
Collapse
Affiliation(s)
- Antoine Perrier
- Department of Environmental Sciences, University of Basel, Basel, Switzerland.,Department of Biology, University of Virginia, Charlottesville, Virginia, USA
| | - Yvonne Willi
- Department of Environmental Sciences, University of Basel, Basel, Switzerland
| |
Collapse
|
16
|
Recent speciation associated with range expansion and a shift to self-fertilization in North American Arabidopsis. Nat Commun 2022; 13:7564. [PMID: 36481740 PMCID: PMC9732334 DOI: 10.1038/s41467-022-35368-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 11/30/2022] [Indexed: 12/13/2022] Open
Abstract
The main processes classically evoked for promoting reproductive isolation and speciation are geographic separation reducing gene flow among populations, divergent selection, and chance genomic change. In a case study, we present evidence that the additional factors of climate change, range expansion and a shift in mating towards inbreeding can initiate the processes leading to parapatric speciation. At the end of the last Pleistocene glaciation cycle, the North American plant Arabidopsis lyrata expanded its range and concomitantly lost its reproductive mode of outcrossing multiple times. We show that in one of the newly colonized areas, the self-fertilizing recolonization lineage of A. lyrata gave rise to selfing A. arenicola, which expanded its range to subarctic and arctic Canada and Greenland, while the parental species remained restricted to temperate North America. Despite the vast range expansion by the new species, mutational load did not increase, probably because of selfing and quasi-clonal selection. We conclude that such peripheral parapatric speciation combined with range expansion and inbreeding may be an important but so far overlooked mode of speciation.
Collapse
|
17
|
Aguirre-Liguori JA, Morales-Cruz A, Gaut BS. Evaluating the persistence and utility of five wild Vitis species in the context of climate change. Mol Ecol 2022; 31:6457-6472. [PMID: 36197804 PMCID: PMC10092629 DOI: 10.1111/mec.16715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 09/23/2022] [Accepted: 09/29/2022] [Indexed: 01/13/2023]
Abstract
Crop wild relatives (CWRs) have the capacity to contribute novel traits to agriculture. Given climate change, these contributions may be especially vital for the persistence of perennial crops, because perennials are often clonally propagated and consequently do not evolve rapidly. By studying the landscape genomics of samples from five Vitis CWRs (V. arizonica, V. mustangensis, V. riparia, V. berlandieri and V. girdiana) in the context of projected climate change, we addressed two goals. The first was to assess the relative potential of different CWR accessions to persist in the face of climate change. By integrating species distribution models with adaptive genetic variation, additional genetic features such as genomic load and a phenotype (resistance to Pierce's Disease), we predicted that accessions from one species (V. mustangensis) are particularly well-suited to persist in future climates. The second goal was to identify which CWR accessions may contribute to bioclimatic adaptation for grapevine (V. vinifera) cultivation. To do so, we evaluated whether CWR accessions have the allelic capacity to persist if moved to locations where grapevines are cultivated in the United States. We identified six candidates from V. mustangensis and hypothesized that they may prove useful for contributing alleles that can mitigate climate impacts on viticulture. By identifying candidate germplasm, this study takes a conceptual step toward assessing the genomic and bioclimatic characteristics of CWRs.
Collapse
Affiliation(s)
- Jonas A Aguirre-Liguori
- Department of Ecology and Evolutionary Biology, University of California, Irvine, California, USA
| | - Abraham Morales-Cruz
- Department of Ecology and Evolutionary Biology, University of California, Irvine, California, USA
| | - Brandon S Gaut
- Department of Ecology and Evolutionary Biology, University of California, Irvine, California, USA
| |
Collapse
|
18
|
Sánchez-Castro D, Armbruster G, Willi Y. Reduced pollinator service in small populations of Arabidopsis lyrata at its southern range limit. Oecologia 2022; 200:107-117. [PMID: 36053350 PMCID: PMC9547784 DOI: 10.1007/s00442-022-05237-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 07/27/2022] [Indexed: 11/28/2022]
Abstract
Even though a high fraction of angiosperm plants depends on animal pollinators for sexual reproduction, little is known how pollinator service changes across the ranges of plant species and whether it may contribute to range limits. Here, we tested for variation in pollinator service in the North American Arabidopsis lyrata from its southern to northern range edge and evaluated the driving mechanisms. We monitored insect pollinators using time-lapse cameras in 13 populations over two years and spotted 67 pollinating insect taxa, indicating the generalist nature of this plant-pollinator system. Pollinator service was highest at intermediate local flower densities and higher in large compared to small plant populations. Southern populations had generally smaller population sizes, and visitation rate and pollination ratio decreased with latitude. We also found that pollinator visitation was positively correlated with the richness of other flowering plants. This study indicates that plant populations at southern range edges receive only marginal pollinator service if they are small, and the effect of lower pollination is also detectable within populations across the range when the local flower density is low. Results, therefore, suggest the potential for an Allee effect in pollination that manifests itself across spatial scales.
Collapse
Affiliation(s)
- Darío Sánchez-Castro
- Department of Environmental Sciences, University of Basel, 4056, Basel, Switzerland.
| | - Georg Armbruster
- Department of Environmental Sciences, University of Basel, 4056, Basel, Switzerland
| | - Yvonne Willi
- Department of Environmental Sciences, University of Basel, 4056, Basel, Switzerland
| |
Collapse
|
19
|
Stetsenko R, Roze D. The evolution of recombination in self-fertilizing organisms. Genetics 2022; 222:6656355. [PMID: 35929790 PMCID: PMC9434187 DOI: 10.1093/genetics/iyac114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Cytological data from flowering plants suggest that the evolution of recombination rates is affected by the mating system of organisms, as higher chiasma frequencies are often observed in self-fertilizing species compared with their outcrossing relatives. Understanding the evolutionary cause of this effect is of particular interest, as it may shed light on the selective forces favoring recombination in natural populations. While previous models showed that inbreeding may have important effects on selection for recombination, existing analytical treatments are restricted to the case of loosely linked loci and weak selfing rates, and ignore the stochastic effect of genetic interference (Hill-Robertson effect), known to be an important component of selection for recombination in randomly mating populations. In this article, we derive general expressions quantifying the stochastic and deterministic components of selection acting on a mutation affecting the genetic map length of a whole chromosome along which deleterious mutations occur, valid for arbitrary selfing rates. The results show that selfing generally increases selection for recombination caused by interference among mutations as long as selection against deleterious alleles is sufficiently weak. While interference is often the main driver of selection for recombination under tight linkage or high selfing rates, deterministic effects can play a stronger role under intermediate selfing rates and high recombination, selecting against recombination in the absence of epistasis, but favoring recombination when epistasis is negative. Individual-based simulation results indicate that our analytical model often provides accurate predictions for the strength of selection on recombination under partial selfing.
Collapse
Affiliation(s)
- Roman Stetsenko
- CNRS, IRL 3614 Evolutionary Biology and Ecology of Algae, 29688 Roscoff, France.,Sorbonne Université, Station Biologique de Roscoff, 29688 Roscoff, France
| | - Denis Roze
- CNRS, IRL 3614 Evolutionary Biology and Ecology of Algae, 29688 Roscoff, France.,Sorbonne Université, Station Biologique de Roscoff, 29688 Roscoff, France
| |
Collapse
|
20
|
Cornille A, Tiret M, Salcedo A, Huang HR, Orsucci M, Milesi P, Kryvokhyzha D, Holm K, Ge XJ, Stinchcombe JR, Glémin S, Wright SI, Lascoux M. The relative role of plasticity and demographic history in Capsella bursa-pastoris: a common garden experiment in Asia and Europe. AOB PLANTS 2022; 14:plac011. [PMID: 35669442 PMCID: PMC9162126 DOI: 10.1093/aobpla/plac011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 03/28/2022] [Indexed: 05/15/2023]
Abstract
The colonization success of a species depends on the interplay between its phenotypic plasticity, adaptive potential and demographic history. Assessing their relative contributions during the different phases of a species range expansion is challenging, and requires large-scale experiments. Here, we investigated the relative contributions of plasticity, performance and demographic history to the worldwide expansion of the shepherd's purse, Capsella bursa-pastoris. We installed two large common gardens of the shepherd's purse, a young, self-fertilizing, allopolyploid weed with a worldwide distribution. One common garden was located in Europe, the other in Asia. We used accessions from three distinct genetic clusters (Middle East, Europe and Asia) that reflect the demographic history of the species. Several life-history traits were measured. To explain the phenotypic variation between and within genetic clusters, we analysed the effects of (i) the genetic clusters, (ii) the phenotypic plasticity and its association to fitness and (iii) the distance in terms of bioclimatic variables between the sampling site of an accession and the common garden, i.e. the environmental distance. Our experiment showed that (i) the performance of C. bursa-pastoris is closely related to its high phenotypic plasticity; (ii) within a common garden, genetic cluster was a main determinant of phenotypic differences; and (iii) at the scale of the experiment, the effect of environmental distance to the common garden could not be distinguished from that of genetic clusters. Phenotypic plasticity and demographic history both play important role at different stages of range expansion. The success of the worldwide expansion of C. bursa-pastoris was undoubtedly influenced by its strong phenotypic plasticity.
Collapse
Affiliation(s)
| | | | | | | | - Marion Orsucci
- Department of Plant Biology, Swedish University of Agricultural Sciences, 750 07 Uppsala, Sweden
| | - Pascal Milesi
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, 75236 Uppsala, Sweden
- Science for Life Laboratory, 752 37 Uppsala, Sweden
| | - Dmytro Kryvokhyzha
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, 75236 Uppsala, Sweden
| | - Karl Holm
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, 75236 Uppsala, Sweden
| | - Xue-Jun Ge
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
- Center of Conservation Biology, Core Botanical Gardens, Chinese Academy of Sciences, Guangzhou 510650, China
| | - John R Stinchcombe
- Department of Ecology and Evolutionary Biology, University of Toronto, M5S 3B2 Toronto, ON, Canada
| | | | | | | |
Collapse
|
21
|
Willi Y, Van Buskirk J. A review on trade-offs at the warm and cold ends of geographical distributions. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210022. [PMID: 35184594 PMCID: PMC8859520 DOI: 10.1098/rstb.2021.0022] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Species’ range limits are ubiquitous. This suggests that the evolution of the ecological niche is constrained in general and at the edges of distributions in particular. While there may be many ecological and genetic reasons for this phenomenon, here we focus on the potential role of trade-offs. We performed a literature search on evidence for trade-offs associated with geographical or elevational range limits. The majority of trade-offs were reported as relevant at either the cold end of species' distribution (n = 19), the warm or dry end (n = 19) or both together (n = 14). One common type of trade-off involved accelerating growth or development (27%), often at the cost of small size. Another common type involved resistance to or tolerance of climatic extremes that occur at certain periods of the year (64%), often at the cost of small size or reduced growth. Trade-offs overlapped with some of the classic trade-offs reported in life-history evolution or thermal adaptation. The results highlight several general insights about species' niches and ranges, and we outline how future research should better integrate the ecological context and test for the presence of microevolutionary trade-offs. This article is part of the theme issue ‘Species’ ranges in the face of changing environments (Part II)’.
Collapse
Affiliation(s)
- Yvonne Willi
- Department of Environmental Sciences, University of Basel, 4056 Basel, Switzerland
| | - Josh Van Buskirk
- Department of Evolutionary Biology and Environmental Studies, University of Zürich, 8057 Zürich, Switzerland
| |
Collapse
|
22
|
Perrier A, Sánchez-Castro D, Willi Y. Environment dependence of the expression of mutational load and species' range limits. J Evol Biol 2022; 35:731-741. [PMID: 35290676 PMCID: PMC9314787 DOI: 10.1111/jeb.13997] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 02/10/2022] [Accepted: 02/21/2022] [Indexed: 12/21/2022]
Abstract
Theoretical and empirical research on the causes of species’ range limits suggest the contribution of several intrinsic and extrinsic factors, with potentially complex interactions among them. An intrinsic factor proposed by recent theory is mutational load increasing towards range edges because of genetic drift. Furthermore, environmental quality may decline towards range edges and enhance the expression of load. Here, we tested whether the expression of mutational load associated with range limits in the North American plant Arabidopsis lyrata was enhanced under stressful environmental conditions by comparing the performance of within‐ versus between‐population crosses at common garden sites across the species’ distribution and beyond. Heterosis, reflecting the expression of load, increased with heightened estimates of genomic load and with environmental stress caused by warming, but the interaction was not significant. We conclude that range‐edge populations suffer from a twofold genetic Allee effect caused by increased mutational load and stress‐dependent load linked to general heterozygote deficiency, but there is no synergistic effect between them.
Collapse
Affiliation(s)
- Antoine Perrier
- Department of Biology, University of Virginia, Charlottesville, Virginia, USA.,Department of Environmental Sciences, University of Basel, Basel, Switzerland
| | | | - Yvonne Willi
- Department of Environmental Sciences, University of Basel, Basel, Switzerland
| |
Collapse
|
23
|
Gilbert KJ, Moinet A, Peischl S. Gene surfing of underdominant alleles promotes formation of hybrid zones. Philos Trans R Soc Lond B Biol Sci 2022; 377:20210006. [PMID: 35067089 PMCID: PMC8784928 DOI: 10.1098/rstb.2021.0006] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Accepted: 07/28/2021] [Indexed: 11/12/2022] Open
Abstract
The distribution of genetic diversity over geographical space has long been investigated in population genetics and serves as a useful tool to understand evolution and history of populations. Within some species or across regions of contact between two species, there are instances where there is no apparent ecological determinant of sharp changes in allele frequencies or divergence. To further understand these patterns of spatial genetic structure and potential species divergence, we model the establishment of clines that occur due to the surfing of underdominant alleles during range expansions. We provide analytical approximations for the fixation probability of underdominant alleles at expansion fronts and demonstrate that gene surfing can lead to clines in one-dimensional range expansions. We extend these results to multiple loci via a mixture of analytical theory and individual-based simulations. We study the interaction between the strength of selection against heterozygotes, migration rates, and local recombination rates on the formation of stable hybrid zones. Clines created by surfing at different loci can attract each other and align after expansion, if they are sufficiently close in space and in terms of recombination distance. Our findings suggest that range expansions can set the stage for parapatric speciation due to the alignment of multiple selective clines, even in the absence of ecologically divergent selection. This article is part of the theme issue 'Species' ranges in the face of changing environments (part I)'.
Collapse
Affiliation(s)
- Kimberly J. Gilbert
- Institute of Plant Sciences, University of Bern, Altenbergrain 21, Bern 3013, Switzerland
| | - Antoine Moinet
- Interfaculty Bioinformatics Unit, University of Bern, Baltzerstrasse 6, Bern 3012, Switzerland
- Institute of Ecology and Evolution, University of Bern, Baltzerstrasse 6, Bern 3012, Switzerland
- Swiss Institute of Bioinformatics, Lausanne 1015, Switzerland
| | - Stephan Peischl
- Interfaculty Bioinformatics Unit, University of Bern, Baltzerstrasse 6, Bern 3012, Switzerland
- Swiss Institute of Bioinformatics, Lausanne 1015, Switzerland
| |
Collapse
|
24
|
Ackiss AS, Magee MR, Sass GG, Turnquist K, McIntyre PB, Larson WA. Genomic and environmental influences on resilience in a cold-water fish near the edge of its range. Evol Appl 2021; 14:2794-2814. [PMID: 34950230 PMCID: PMC8674893 DOI: 10.1111/eva.13313] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 10/05/2021] [Accepted: 10/07/2021] [Indexed: 02/06/2023] Open
Abstract
Small, isolated populations present a challenge for conservation. The dueling effects of selection and drift in a limited pool of genetic diversity make the responses of small populations to environmental perturbations erratic and difficult to predict. This is particularly true at the edge of a species range, where populations often persist at the limits of their environmental tolerances. Populations of cisco, Coregonus artedi, in inland lakes have experienced numerous extirpations along the southern edge of their range in recent decades, which are thought to result from environmental degradation and loss of cold, well-oxygenated habitat as lakes warm. Yet, cisco extirpations do not show a clear latitudinal pattern, suggesting that local environmental factors and potentially local adaptation may influence resilience. Here, we used genomic tools to investigate the nature of this pattern of resilience. We used restriction site-associated DNA capture (Rapture) sequencing to survey genomic diversity and differentiation in southern inland lake cisco populations and compared the frequency of deleterious mutations that potentially influence fitness across lakes. We also examined haplotype diversity in a region of the major histocompatibility complex involved in stress and immune system response. We correlated these metrics to spatial and environmental factors including latitude, lake size, and measures of oxythermal habitat and found significant relationships between genetic metrics and broad and local factors. High levels of genetic differentiation among populations were punctuated by a phylogeographic break and residual patterns of isolation-by-distance. Although the prevalence of deleterious mutations and inbreeding coefficients was significantly correlated with latitude, neutral and non-neutral genetic diversity were most strongly correlated with lake surface area. Notably, differences among lakes in the availability of estimated oxythermal habitat left no clear population genomic signature. Our results shed light on the complex dynamics influencing these isolated populations and provide valuable information for their conservation.
Collapse
Affiliation(s)
- Amanda S. Ackiss
- Wisconsin Cooperative Fishery Research UnitCollege of Natural ResourcesUniversity of Wisconsin‐Stevens PointStevens PointWisconsinUSA
- U.S. Geological SurveyGreat Lakes Science CenterAnn ArborMichiganUSA
| | | | - Greg G. Sass
- Escanaba Lake Research StationWisconsin Department of Natural ResourcesBoulder JunctionWisconsinUSA
| | - Keith Turnquist
- Wisconsin Cooperative Fishery Research UnitCollege of Natural ResourcesUniversity of Wisconsin‐Stevens PointStevens PointWisconsinUSA
| | - Peter B. McIntyre
- Department of Natural Resources and the EnvironmentCornell UniversityIthacaNew YorkUSA
| | - Wesley A. Larson
- U.S. Geological SurveyWisconsin Cooperative Fishery Research UnitCollege of Natural ResourcesUniversity of Wisconsin‐Stevens PointStevens PointWisconsinUSA
- National Oceanographic and Atmospheric AdministrationNational Marine Fisheries ServiceAlaska Fisheries Science CenterAuke Bay LaboratoriesJuneauAlaskaUSA
| |
Collapse
|
25
|
The evolutionary genomics of species' responses to climate change. Nat Ecol Evol 2021; 5:1350-1360. [PMID: 34373621 DOI: 10.1038/s41559-021-01526-9] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 07/05/2021] [Indexed: 02/06/2023]
Abstract
Climate change is a threat to biodiversity. One way that this threat manifests is through pronounced shifts in the geographical range of species over time. To predict these shifts, researchers have primarily used species distribution models. However, these models are based on assumptions of niche conservatism and do not consider evolutionary processes, potentially limiting their accuracy and value. To incorporate evolution into the prediction of species' responses to climate change, researchers have turned to landscape genomic data and examined information about local genetic adaptation using climate models. Although this is an important advancement, this approach currently does not include other evolutionary processes-such as gene flow, population dispersal and genomic load-that are critical for predicting the fate of species across the landscape. Here, we briefly review the current practices for the use of species distribution models and for incorporating local adaptation. We next discuss the rationale and theory for considering additional processes, reviewing how they can be incorporated into studies of species' responses to climate change. We summarize with a conceptual framework of how manifold layers of information can be combined to predict the potential response of specific populations to climate change. We illustrate all of the topics using an exemplar dataset and provide the source code as potential tutorials. This Perspective is intended to be a step towards a more comprehensive integration of population genomics with climate change science.
Collapse
|
26
|
Draining the Swamping Hypothesis: Little Evidence that Gene Flow Reduces Fitness at Range Edges. Trends Ecol Evol 2021; 36:533-544. [DOI: 10.1016/j.tree.2021.02.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Revised: 01/27/2021] [Accepted: 02/05/2021] [Indexed: 11/23/2022]
|
27
|
Capblancq T, Munson H, Butnor JR, Keller SR. Genomic drivers of early-life fitness in Picea rubens. CONSERV GENET 2021. [DOI: 10.1007/s10592-021-01378-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
28
|
İltaş Ö, Svitok M, Cornille A, Schmickl R, Lafon Placette C. Early evolution of reproductive isolation: A case of weak inbreeder/strong outbreeder leads to an intraspecific hybridization barrier in Arabidopsis lyrata. Evolution 2021; 75:1466-1476. [PMID: 33900634 DOI: 10.1111/evo.14240] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 02/08/2021] [Accepted: 04/10/2021] [Indexed: 12/18/2022]
Abstract
Reproductive strategies play a major role in plant speciation. Notably, transitions from outcrossing to selfing may lead to relaxed sexual selection and parental conflict. Shifts in mating systems can affect maternal and paternal interests, and thus parent-specific influence on endosperm development, leading to reproductive isolation: if selfing and outcrossing species hybridize, the resulting seeds may not be viable due to endosperm failure. Nevertheless, it remains unclear how the switch in mating systems can impact reproductive isolation between recently diverged lineages, that is, during the process of speciation. We investigated this question using Arabidopsis lyrata, which recently transitioned to selfing (10,000 years ago) in certain North American populations, where European populations remain outcrossing. We performed reciprocal crosses between selfers and outcrossers, and measured seed viability and endosperm development. We show that parental genomes in the hybrid seed negatively interact, as predicted by parental conflict. This leads to extensive hybrid seed lethality associated with endosperm cellularization disturbance. Our results suggest that this is primarily driven by divergent evolution of the paternal genome between selfers and outcrossers. In addition, we observed other hybrid seed defects, suggesting that sex-specific interests are not the only processes contributing to postzygotic reproductive isolation.
Collapse
Affiliation(s)
- Ömer İltaş
- Department of Botany, Faculty of Science, Charles University, Prague, CZ-128 01, Czech Republic
| | - Marek Svitok
- Faculty of Ecology and Environmental Sciences, Technical University in Zvolen, Zvolen, SK-960 01, Slovakia.,Department of Ecosystem Biology, Faculty of Science, University of South Bohemia, České Budějovice, CZ-370 05, Czech Republic
| | - Amandine Cornille
- Université Paris-Saclay, INRAE, CNRS, AgroParisTech, GQE-Le Moulon, Gif-sur-Yvette, 91190, France
| | - Roswitha Schmickl
- Department of Botany, Faculty of Science, Charles University, Prague, CZ-128 01, Czech Republic.,Institute of Botany, The Czech Academy of Sciences, Průhonice, CZ-252 43, Czech Republic
| | - Clément Lafon Placette
- Department of Botany, Faculty of Science, Charles University, Prague, CZ-128 01, Czech Republic
| |
Collapse
|
29
|
Bontrager M, Usui T, Lee-Yaw JA, Anstett DN, Branch HA, Hargreaves AL, Muir CD, Angert AL. Adaptation across geographic ranges is consistent with strong selection in marginal climates and legacies of range expansion. Evolution 2021; 75:1316-1333. [PMID: 33885152 DOI: 10.1111/evo.14231] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 03/14/2021] [Indexed: 12/27/2022]
Abstract
Every species experiences limits to its geographic distribution. Some evolutionary models predict that populations at range edges are less well adapted to their local environments due to drift, expansion load, or swamping gene flow from the range interior. Alternatively, populations near range edges might be uniquely adapted to marginal environments. In this study, we use a database of transplant studies that quantify performance at broad geographic scales to test how local adaptation, site quality, and population quality change from spatial and climatic range centers toward edges. We find that populations from poleward edges perform relatively poorly, both on average across all sites (15% lower population quality) and when compared to other populations at home (31% relative fitness disadvantage), consistent with these populations harboring high genetic load. Populations from equatorial edges also perform poorly on average (18% lower population quality) but, in contrast, outperform foreign populations (16% relative fitness advantage), suggesting that populations from equatorial edges have strongly adapted to unique environments. Finally, we find that populations from sites that are thermally extreme relative to the species' niche demonstrate strong local adaptation, regardless of their geographic position. Our findings indicate that both nonadaptive processes and adaptive evolution contribute to variation in adaptation across species' ranges.
Collapse
Affiliation(s)
- Megan Bontrager
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, V6T 1Z4, Canada.,Current Address: Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, M5S 3B2, Canada
| | - Takuji Usui
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, V6T 1Z4, Canada
| | - Julie A Lee-Yaw
- Department of Biological Sciences, University of Lethbridge, Lethbridge, T1K 3M4, Canada
| | - Daniel N Anstett
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, V6T 1Z4, Canada
| | - Haley A Branch
- Department of Botany and Biodiversity Research Centre, University of British Columbia, Vancouver, V6T 1Z4, Canada
| | | | - Christopher D Muir
- School of Life Sciences, University of Hawaii, Honolulu, Hawaii, 96822, United States
| | - Amy L Angert
- Departments of Botany and Zoology and the Biodiversity Research Centre, University of British Columbia, Vancouver, V6T 1Z4, Canada
| |
Collapse
|
30
|
Takou M, Hämälä T, Koch EM, Steige KA, Dittberner H, Yant L, Genete M, Sunyaev S, Castric V, Vekemans X, Savolainen O, de Meaux J. Maintenance of Adaptive Dynamics and No Detectable Load in a Range-Edge Outcrossing Plant Population. Mol Biol Evol 2021; 38:1820-1836. [PMID: 33480994 PMCID: PMC8097302 DOI: 10.1093/molbev/msaa322] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
During range expansion, edge populations are expected to face increased genetic drift, which in turn can alter and potentially compromise adaptive dynamics, preventing the removal of deleterious mutations and slowing down adaptation. Here, we contrast populations of the European subspecies Arabidopsis lyrata ssp. petraea, which expanded its Northern range after the last glaciation. We document a sharp decline in effective population size in the range-edge population and observe that nonsynonymous variants segregate at higher frequencies. We detect a 4.9% excess of derived nonsynonymous variants per individual in the range-edge population, suggesting an increase of the genomic burden of deleterious mutations. Inference of the fitness effects of mutations and modeling of allele frequencies under the explicit demographic history of each population predicts a depletion of rare deleterious variants in the range-edge population, but an enrichment for fixed ones, consistent with the bottleneck effect. However, the demographic history of the range-edge population predicts a small net decrease in per-individual fitness. Consistent with this prediction, the range-edge population is not impaired in its growth and survival measured in a common garden experiment. We further observe that the allelic diversity at the self-incompatibility locus, which ensures strict outcrossing and evolves under negative frequency-dependent selection, has remained unchanged. Genomic footprints indicative of selective sweeps are broader in the Northern population but not less frequent. We conclude that the outcrossing species A. lyrata ssp. petraea shows a strong resilience to the effect of range expansion.
Collapse
Affiliation(s)
- Margarita Takou
- Institute of Botany, University of Cologne, Cologne, Germany
| | - Tuomas Hämälä
- Department of Plant and Microbial Biology, University of Minnesota, St. Paul, MN, USA
| | - Evan M Koch
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA, USA
| | - Kim A Steige
- Institute of Botany, University of Cologne, Cologne, Germany
| | | | - Levi Yant
- School of Life Sciences, University of Nottingham, Nottingham, United Kingdom
| | - Mathieu Genete
- CNRS, UMR 8198 – Evo-Eco-Paleo, University of Lille, Lille, France
| | - Shamil Sunyaev
- Department of Biomedical Informatics, Harvard Medical School, Boston, MA, USA
| | - Vincent Castric
- CNRS, UMR 8198 – Evo-Eco-Paleo, University of Lille, Lille, France
| | - Xavier Vekemans
- CNRS, UMR 8198 – Evo-Eco-Paleo, University of Lille, Lille, France
| | - Outi Savolainen
- Department of Ecology and Genetics, University of Oulu, Oulu, Finland
| | | |
Collapse
|
31
|
Lucek K, Willi Y. Drivers of linkage disequilibrium across a species' geographic range. PLoS Genet 2021; 17:e1009477. [PMID: 33770075 PMCID: PMC8026057 DOI: 10.1371/journal.pgen.1009477] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 04/07/2021] [Accepted: 03/09/2021] [Indexed: 11/25/2022] Open
Abstract
While linkage disequilibrium (LD) is an important parameter in genetics and evolutionary biology, the drivers of LD remain elusive. Using whole-genome sequences from across a species’ range, we assessed the impact of demographic history and mating system on LD. Both range expansion and a shift from outcrossing to selfing in North American Arabidopsis lyrata were associated with increased average genome-wide LD. Our results indicate that range expansion increases short-distance LD at the farthest range edges by about the same amount as a shift to selfing. However, the extent over which LD in genic regions unfolds was shorter for range expansion compared to selfing. Linkage among putatively neutral variants and between neutral and deleterious variants increased to a similar degree with range expansion, providing support that genome-wide LD was positively associated with mutational load. As a consequence, LD combined with mutational load may decelerate range expansions and set range limits. Finally, a small number of genes were identified as LD outliers, suggesting that they experience selection by either of the two demographic processes. These included genes involved in flowering and photoperiod for range expansion, and the self-incompatibility locus for mating system. Nearby genomic variants are often co-inherited because of limited recombination. The extent of non-random association of alleles at different loci is called linkage disequilibrium (LD) and is commonly used in genomic analyses, for example to detect regions under selection or to determine effective population size. Here we reversed testing and addressed how demographic history may affect LD within a species. Using genomic data from more than a thousand individuals of North American Arabidopsis lyrata from across the entire species’ range, we quantified the effect of postglacial range expansion and a shift in mating system from outcrossing to selfing on LD. We show that both factors lead to increased LD, and that the maximal effect of range expansion is comparable with a shift in mating system to selfing. Heightened LD involves deleterious mutations, and therefore, LD can also serve as an indicator of mutation accumulation. Furthermore, we provide evidence that some genes experienced stronger increases in LD possibly due to selection associated with the two demographic changes. Our results provide a novel and broad view on the evolutionary factors shaping LD that may also apply to the very many species that underwent postglacial range expansion.
Collapse
Affiliation(s)
- Kay Lucek
- Department of Environmental Sciences, University of Basel, Basel, Switzerland
- * E-mail:
| | - Yvonne Willi
- Department of Environmental Sciences, University of Basel, Basel, Switzerland
| |
Collapse
|
32
|
de Pedro M, Riba M, González-Martínez SC, Seoane P, Bautista R, Claros MG, Mayol M. Demography, genetic diversity and expansion load in the colonizing species Leontodon longirostris (Asteraceae) throughout its native range. Mol Ecol 2021; 30:1190-1205. [PMID: 33452714 DOI: 10.1111/mec.15802] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 12/12/2020] [Accepted: 01/08/2021] [Indexed: 12/25/2022]
Abstract
Unravelling the evolutionary processes underlying range expansions is fundamental to understand the distribution of organisms, as well as to predict their future responses to environmental change. Predictions for range expansions include a loss of genetic diversity and an accumulation of deleterious alleles along the expansion axis, which can decrease fitness at the range-front (expansion load). In plants, empirical studies supporting expansion load are scarce, and its effects remain to be tested outside a few model species. Leontodon longirostris is a colonizing Asteraceae with a widespread distribution in the Western Mediterranean, providing a particularly interesting system to gain insight into the factors that can enhance or mitigate expansion load. In this study, we produced a first genome draft for the species, covering 418 Mbp (~53% of the genome). Although incomplete, this draft was suitable to design a targeted sequencing of ~1.5 Mbp in 238 L. longirostris plants from 21 populations distributed along putative colonization routes in the Iberian Peninsula. Inferred demographic history supports a range expansion from southern Iberia around 40,000 years ago, reaching northern Iberia around 25,000 years ago. The expansion was accompanied by a loss of genetic diversity and a significant increase in the proportion of putatively deleterious mutations. However, levels of expansion load in L. longirostris were smaller than those found in other plant species, which can be explained, at least partially, by its high dispersal ability, the self-incompatible mating system, and the fact that the expansion occurred along a strong environmental cline.
Collapse
Affiliation(s)
| | - Miquel Riba
- CREAF, Cerdanyola del Vallès, Spain.,Univ. Autònoma Barcelona, Cerdanyola del Vallès, Spain
| | | | - Pedro Seoane
- Department of Molecular Biology and Biochemistry, Universidad de Málaga, and Institute for Mediterranean and Subtropical Horticulture (IHSM-CSIC-UMA), Málaga, Spain.,CIBER de Enfermedades Raras (CIBERER), Málaga, Spain.,Institute of Biomedical Research in Malaga (IBIMA), IBIMA-RARE, Málaga, Spain
| | - Rocío Bautista
- Institute of Biomedical Research in Malaga (IBIMA), IBIMA-RARE, Málaga, Spain.,Andalusian Platform for Bioinformatics-SCBI, Universidad de Málaga, Málaga, Spain
| | - Manuel Gonzalo Claros
- Department of Molecular Biology and Biochemistry, Universidad de Málaga, and Institute for Mediterranean and Subtropical Horticulture (IHSM-CSIC-UMA), Málaga, Spain.,CIBER de Enfermedades Raras (CIBERER), Málaga, Spain.,Institute of Biomedical Research in Malaga (IBIMA), IBIMA-RARE, Málaga, Spain.,Andalusian Platform for Bioinformatics-SCBI, Universidad de Málaga, Málaga, Spain.,Institute for Mediterranean and Subtropical Horticulture "La Mayora" (IHSM-UMA-CSIC), Málaga, Spain
| | | |
Collapse
|
33
|
Wieters B, Steige KA, He F, Koch EM, Ramos-Onsins SE, Gu H, Guo YL, Sunyaev S, de Meaux J. Polygenic adaptation of rosette growth in Arabidopsis thaliana. PLoS Genet 2021; 17:e1008748. [PMID: 33493157 PMCID: PMC7861555 DOI: 10.1371/journal.pgen.1008748] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 02/04/2021] [Accepted: 12/10/2020] [Indexed: 12/16/2022] Open
Abstract
The rate at which plants grow is a major functional trait in plant ecology. However, little is known about its evolution in natural populations. Here, we investigate evolutionary and environmental factors shaping variation in the growth rate of Arabidopsis thaliana. We used plant diameter as a proxy to monitor plant growth over time in environments that mimicked latitudinal differences in the intensity of natural light radiation, across a set of 278 genotypes sampled within four broad regions, including an outgroup set of genotypes from China. A field experiment conducted under natural conditions confirmed the ecological relevance of the observed variation. All genotypes markedly expanded their rosette diameter when the light supply was decreased, demonstrating that environmental plasticity is a predominant source of variation to adapt plant size to prevailing light conditions. Yet, we detected significant levels of genetic variation both in growth rate and growth plasticity. Genome-wide association studies revealed that only 2 single nucleotide polymorphisms associate with genetic variation for growth above Bonferroni confidence levels. However, marginally associated variants were significantly enriched among genes with an annotated role in growth and stress reactions. Polygenic scores computed from marginally associated variants confirmed the polygenic basis of growth variation. For both light regimes, phenotypic divergence between the most distantly related population (China) and the various regions in Europe is smaller than the variation observed within Europe, indicating that the evolution of growth rate is likely to be constrained by stabilizing selection. We observed that Spanish genotypes, however, reach a significantly larger size than Northern European genotypes. Tests of adaptive divergence and analysis of the individual burden of deleterious mutations reveal that adaptive processes have played a more important role in shaping regional differences in rosette growth than maladaptive evolution. The rate at which plants grow is a major functional trait in plant ecology. However, little is known about its genetic variation in natural populations. Here, we investigate genetic and environmental factors shaping variation in the growth rate of Arabidopsis thaliana and ask whether genetic variation in plant growth contributes to adaptation to local environmental conditions. We grew plants under two light regimes that mimic latitudinal differences in the intensity of natural light radiation, and measured plant diameter as it grew over time. When the light supply was decreased, plant diameter grew more slowly but reached a markedly larger final size, confirming that plants can adjust their growth to prevailing light conditions. Yet, we also detected significant levels of genetic variation both in growth rate and in how the growth dynamics is adjusted to the light conditions. We show that this variation is encoded by many loci of small effect that are hard to locate in the genome but overall significantly enriched among genes associated with growth and stress reactions. We further observe that Spanish genotypes tended to reach, on average, a significantly larger rosette size than Northern European genotypes. Tests of adaptive divergence indicate that these differences may reflect adaptation to local environmental conditions.
Collapse
Affiliation(s)
| | - Kim A. Steige
- Institute of Botany, University of Cologne, Cologne, Germany
| | - Fei He
- Institute of Botany, University of Cologne, Cologne, Germany
| | - Evan M. Koch
- Genetics Division, Brigham & Women's Hospital and Harvard Medical School, Boston MA, United States of America
- Department of Biomedical Informatics, Harvard Medical School, Boston MA, United States of America
| | | | - Hongya Gu
- State Key Laboratory for Protein and Plant Gene Research, College of Life Sciences, Peking University, Beijing, China
| | - Ya-Long Guo
- State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, China
| | - Shamil Sunyaev
- Genetics Division, Brigham & Women's Hospital and Harvard Medical School, Boston MA, United States of America
- Department of Biomedical Informatics, Harvard Medical School, Boston MA, United States of America
| | - Juliette de Meaux
- Institute of Botany, University of Cologne, Cologne, Germany
- * E-mail:
| |
Collapse
|
34
|
Castillo D, Lavrentovich MO. Shape of population interfaces as an indicator of mutational instability in coexisting cell populations. Phys Biol 2020; 17:066002. [PMID: 33210619 DOI: 10.1088/1478-3975/abb2dd] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Cellular populations such as avascular tumors and microbial biofilms may 'invade' or grow into surrounding populations. The invading population is often comprised of a heterogeneous mixture of cells with varying growth rates. The population may also exhibit mutational instabilities, such as a heavy deleterious mutation load in a cancerous growth. We study the dynamics of a heterogeneous, mutating population competing with a surrounding homogeneous population, as one might find in a cancerous invasion of healthy tissue. We find that the shape of the population interface serves as an indicator for the evolutionary dynamics within the heterogeneous population. In particular, invasion front undulations become enhanced when the invading population is near a mutational meltdown transition or when the surrounding 'bystander' population is barely able to reinvade the mutating population. We characterize these interface undulations and the effective fitness of the heterogeneous population in one- and two-dimensional systems.
Collapse
Affiliation(s)
- Daniel Castillo
- Department of Physics & Astronomy, University of Tennessee, Knoxville, Tennessee 37996, United States of America
| | | |
Collapse
|
35
|
Willi Y, Fracassetti M, Bachmann O, Van Buskirk J. Demographic Processes Linked to Genetic Diversity and Positive Selection across a Species' Range. PLANT COMMUNICATIONS 2020; 1:100111. [PMID: 33367266 PMCID: PMC7747977 DOI: 10.1016/j.xplc.2020.100111] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 07/27/2020] [Accepted: 09/09/2020] [Indexed: 06/12/2023]
Abstract
Demography determines the strength of genetic drift, which generally reduces genetic variation and the efficacy of selection. Here, we disentangled the importance of demographic processes at a local scale (census size and mating system) and at a species-range scale (old split between population clusters, recolonization after the last glaciation cycle, and admixture) in determining within-population genomic diversity and genomic signatures of positive selection. Analyses were based on re-sequence data from 52 populations of North American Arabidopsis lyrata collected across its entire distribution. The mating system and range dynamics since the last glaciation cycle explained around 60% of the variation in genomic diversity among populations and 52% of the variation in the signature of positive selection. Diversity was lowest in selfing compared with outcrossing populations and in areas further away from glacial refugia. In parallel, reduced positive selection was found in selfing populations and in populations with a longer route of postglacial range expansion. The signature of positive selection was also reduced in populations without admixture. We conclude that recent range expansion can have a profound influence on diversity in coding and non-coding DNA, similar in magnitude to the shift toward selfing. Distribution limits may in fact be caused by reduced effective population size and compromised positive selection in recently colonized parts of the range.
Collapse
Affiliation(s)
- Yvonne Willi
- Department of Environmental Sciences, University of Basel, Schönbeinstrasse 6, CH-4056 Basel, Switzerland
| | - Marco Fracassetti
- Department of Environmental Sciences, University of Basel, Schönbeinstrasse 6, CH-4056 Basel, Switzerland
| | - Olivier Bachmann
- Department of Environmental Sciences, University of Basel, Schönbeinstrasse 6, CH-4056 Basel, Switzerland
| | - Josh Van Buskirk
- Department of Evolutionary Biology and Environmental Studies, University of Zürich, CH-8057 Zürich, Switzerland
| |
Collapse
|
36
|
Angert AL, Bontrager MG, Ågren J. What Do We Really Know About Adaptation at Range Edges? ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2020. [DOI: 10.1146/annurev-ecolsys-012120-091002] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Recent theory and empirical evidence have provided new insights regarding how evolutionary forces interact to shape adaptation at stable and transient range margins. Predictions regarding trait divergence at leading edges are frequently supported. However, declines in fitness at and beyond edges show that trait divergence has sometimes been insufficient to maintain high fitness, so identifying constraints to adaptation at range edges remains a key challenge. Indirect evidence suggests that range expansion may be limited by adaptive genetic variation, but direct estimates of genetic constraints at and beyond range edges are still scarce. Sequence data suggest increased genetic load in edge populations in several systems, but its causes and fitness consequences are usually poorly understood. The balance between maladaptive and positive effects of gene flow on fitness at range edges deserves further study. It is becoming increasingly clear that characterizations about degree of adaptation based solely on geographical peripherality are unsupported.
Collapse
Affiliation(s)
- Amy L. Angert
- Departments of Botany and Zoology, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Megan G. Bontrager
- Department of Evolution and Ecology, University of California, Davis, California 95616, USA
| | - Jon Ågren
- Department of Ecology and Genetics, Uppsala University, SE-752 36 Uppsala, Sweden
| |
Collapse
|
37
|
Prior CJ, Layman NC, Koski MH, Galloway LF, Busch JW. Westward range expansion from middle latitudes explains the Mississippi River discontinuity in a forest herb of eastern North America. Mol Ecol 2020; 29:4473-4486. [PMID: 32978776 DOI: 10.1111/mec.15650] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 09/01/2020] [Accepted: 09/04/2020] [Indexed: 01/22/2023]
Abstract
It is often expected that temperate plants have expanded their geographical ranges northward from primarily southern refugia. Evidence for this hypothesis is mixed in eastern North American species, and there is increasing support for colonization from middle latitudes. We studied genome-wide patterns of variation in RADseq loci to test hypotheses concerning range expansion in a North American forest herb (Campanula americana). First, spatial patterns of genetic differentiation were determined. Then phylogenetic relationships and divergence times were estimated. Spatial signatures of genetic drift were also studied to identify the directionality of recent range expansion and its geographical origins. Finally, spatially explicit scenarios for the spread of plants across the landscape were compared, using variation in the population mutation parameter and Tajima's D. We found strong longitudinal subdivision, with populations clustering into groups west and east of the Mississippi River. While the southeastern region was probably part of a diverse Pleistocene refugium, there is little evidence that range expansion involved founders from these southern locales. Instead, declines in genetic diversity and the loss of rare alleles support a westward colonization wave from a middle latitude refugium near the southern Appalachian Mountains, with subsequent expansion from a Pleistocene staging ground in the Mississippi River Valley (0.51-1.27 million years ago). These analyses implicate stepping stone colonization from middle latitudes as an important mechanism of species range expansion in eastern North America. This study further demonstrates the utility of population genetics as a tool to infer the routes travelled by organisms during geographical range expansion.
Collapse
Affiliation(s)
- Carly J Prior
- School of Biological Sciences, Washington State University, Pullman, WA, USA
| | - Nathan C Layman
- School of Biological Sciences, Washington State University, Pullman, WA, USA
| | - Matthew H Koski
- Department of Biological Sciences, Clemson University, Clemson, SC, USA
| | - Laura F Galloway
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Jeremiah W Busch
- School of Biological Sciences, Washington State University, Pullman, WA, USA
| |
Collapse
|
38
|
Miller TEX, Angert AL, Brown CD, Lee-Yaw JA, Lewis M, Lutscher F, Marculis NG, Melbourne BA, Shaw AK, Szűcs M, Tabares O, Usui T, Weiss-Lehman C, Williams JL. Eco-evolutionary dynamics of range expansion. Ecology 2020; 101:e03139. [PMID: 32697876 DOI: 10.1002/ecy.3139] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Revised: 05/05/2020] [Accepted: 06/08/2020] [Indexed: 01/31/2023]
Abstract
Understanding the movement of species' ranges is a classic ecological problem that takes on urgency in this era of global change. Historically treated as a purely ecological process, range expansion is now understood to involve eco-evolutionary feedbacks due to spatial genetic structure that emerges as populations spread. We synthesize empirical and theoretical work on the eco-evolutionary dynamics of range expansion, with emphasis on bridging directional, deterministic processes that favor evolved increases in dispersal and demographic traits with stochastic processes that lead to the random fixation of alleles and traits. We develop a framework for understanding the joint influence of these processes in changing the mean and variance of expansion speed and its underlying traits. Our synthesis of recent laboratory experiments supports the consistent role of evolution in accelerating expansion speed on average, and highlights unexpected diversity in how evolution can influence variability in speed: results not well predicted by current theory. We discuss and evaluate support for three classes of modifiers of eco-evolutionary range dynamics (landscape context, trait genetics, and biotic interactions), identify emerging themes, and suggest new directions for future work in a field that stands to increase in relevance as populations move in response to global change.
Collapse
Affiliation(s)
- Tom E X Miller
- Program in Ecology and Evolutionary Biology, Department of BioSciences, Rice University, Houston, Texas, 77005, USA
| | - Amy L Angert
- Department of Botany, University of British Columbia, Vancouver, British Columbia, V6T 1Z2, Canada
| | - Carissa D Brown
- Department of Geography, Memorial University, 230 Elizabeth Avenue, St John's, Newfoundland and Labrador, A1B 3X9, Canada
| | - Julie A Lee-Yaw
- Department of Botany, University of British Columbia, Vancouver, British Columbia, V6T 1Z2, Canada.,Department of Biological Sciences, University of Lethbridge, 4401 University Drive, Lethbridge, Alberta, T1K 3M4, Canada
| | - Mark Lewis
- Department of Mathematical and Statistical Sciences, University of Alberta, Edmonton, Alberta, T6G 2G1, Canada.,Department of Biological Sciences, University of Alberta, Edmonton, Alberta, T6G 2G1, Canada
| | - Frithjof Lutscher
- Department of Mathematics and Statistics, and Department of Biology, University of Ottawa, Ottawa, Ottawa, K1N 6N5, Canada
| | - Nathan G Marculis
- Department of Mathematical and Statistical Sciences, University of Alberta, Edmonton, Alberta, T6G 2G1, Canada.,Department of Environmental Science and Policy, University of California-Davis, Davis, California, 95616, USA
| | - Brett A Melbourne
- Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, Colorado, 80309, USA
| | - Allison K Shaw
- Department of Ecology, Evolution, and Behavior, University of Minnesota, St. Paul, Minnesota, 55108, USA
| | - Marianna Szűcs
- Department of Entomology, Michigan State University, 288 Farm Lane, East Lansing, Michigan, 48824, USA
| | - Olivia Tabares
- Department of Geography and Biodiversity Research Centre, University of British Columbia, 1984 West Mall, Vancouver, British Columbia, V6T 1Z2, Canada
| | - Takuji Usui
- Department of Botany, University of British Columbia, Vancouver, British Columbia, V6T 1Z2, Canada
| | - Christopher Weiss-Lehman
- Department of Ecology, Evolution, and Behavior, University of Minnesota, St. Paul, Minnesota, 55108, USA
| | - Jennifer L Williams
- Department of Geography and Biodiversity Research Centre, University of British Columbia, 1984 West Mall, Vancouver, British Columbia, V6T 1Z2, Canada
| |
Collapse
|
39
|
Jones MR, Mills LS, Jensen JD, Good JM. The Origin and Spread of Locally Adaptive Seasonal Camouflage in Snowshoe Hares. Am Nat 2020; 196:316-332. [DOI: 10.1086/710022] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
40
|
Rougemont Q, Moore JS, Leroy T, Normandeau E, Rondeau EB, Withler RE, Van Doornik DM, Crane PA, Naish KA, Garza JC, Beacham TD, Koop BF, Bernatchez L. Demographic history shaped geographical patterns of deleterious mutation load in a broadly distributed Pacific Salmon. PLoS Genet 2020; 16:e1008348. [PMID: 32845885 PMCID: PMC7478589 DOI: 10.1371/journal.pgen.1008348] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 09/08/2020] [Accepted: 06/24/2020] [Indexed: 12/24/2022] Open
Abstract
A thorough reconstruction of historical processes is essential for a comprehensive understanding of the mechanisms shaping patterns of genetic diversity. Indeed, past and current conditions influencing effective population size have important evolutionary implications for the efficacy of selection, increased accumulation of deleterious mutations, and loss of adaptive potential. Here, we gather extensive genome-wide data that represent the extant diversity of the Coho salmon (Oncorhynchus kisutch) to address two objectives. We demonstrate that a single glacial refugium is the source of most of the present-day genetic diversity, with detectable inputs from a putative secondary micro-refugium. We found statistical support for a scenario whereby ancestral populations located south of the ice sheets expanded recently, swamping out most of the diversity from other putative micro-refugia. Demographic inferences revealed that genetic diversity was also affected by linked selection in large parts of the genome. Moreover, we demonstrate that the recent demographic history of this species generated regional differences in the load of deleterious mutations among populations, a finding that mirrors recent results from human populations and provides increased support for models of expansion load. We propose that insights from these historical inferences should be better integrated in conservation planning of wild organisms, which currently focuses largely on neutral genetic diversity and local adaptation, with the role of potentially maladaptive variation being generally ignored. Reconstruction of a species’ past demographic history from genetic data can highlight historical factors that have shaped the distribution of genetic diversity along its genome and its geographic range. Here, we combine genotyping-by-sequencing with demographic modelling to address these issues in the Coho salmon, a Pacific salmon of conservation concern in some parts of its range, notably in the south. Our demographic reconstructions reveal a linear decrease in genetic diversity toward the north of the species range, supporting the hypothesis of a northern route of postglacial recolonization from a single major southern refugium. As predicted by theory, we also observed a higher proportion of deleterious mutations in the most distant populations from this refugium. Beyond this general pattern, among-site variation in the proportion of deleterious mutations is consistent with different local trends in effective population sizes. Our results highlight the potential importance of understanding historical factors that have shaped geographic patterns of the distribution of deleterious mutations in order to implement effective management programs for the conservation of wild populations. Such fundamental knowledge of human historical demography is now having major impacts on health sciences, and we argue it is time to integrate such approaches in conservation science as well.
Collapse
Affiliation(s)
- Quentin Rougemont
- Département de Biologie, Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Québec, Canada
- * E-mail:
| | - Jean-Sébastien Moore
- Département de Biologie, Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Québec, Canada
| | - Thibault Leroy
- ISEM, Univ. Montpellier, CNRS, EPHE, IRD, Montpellier, France
- Department of Botany & Biodiversity Research, University of Vienna, Vienna, Austria
| | - Eric Normandeau
- Département de Biologie, Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Québec, Canada
| | - Eric B. Rondeau
- Centre for Biomedical Research, University of Victoria, Victoria, BC, Canada
- Department of Biology, University of Victoria, Victoria, BC, Canada
| | - Ruth E. Withler
- Department of Fisheries and Ocean, Pacific Biological Station, Nanaimo, British Columbia, Canada
| | - Donald M. Van Doornik
- National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Northwest Fisheries Science Center, Manchester Research Station, Port Orchard, Washington, United States of America
| | - Penelope A. Crane
- Conservation Genetics Laboratory, U.S. Fish and Wildlife Service, Anchorage, Alaska, United States of America
| | - Kerry A. Naish
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA, United States of America
| | - John Carlos Garza
- Fisheries Ecology Division, Southwest Fisheries Science Center, National Marine Fisheries Service and Institute of Marine Sciences, University of California–Santa Cruz, Santa Cruz, California, United States of America
| | - Terry D. Beacham
- Department of Fisheries and Ocean, Pacific Biological Station, Nanaimo, British Columbia, Canada
| | - Ben F. Koop
- Centre for Biomedical Research, University of Victoria, Victoria, BC, Canada
- Department of Biology, University of Victoria, Victoria, BC, Canada
| | - Louis Bernatchez
- Département de Biologie, Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, Québec, Canada
| |
Collapse
|
41
|
The spatial Muller's ratchet: Surfing of deleterious mutations during range expansion. Theor Popul Biol 2020; 135:19-31. [PMID: 32818523 DOI: 10.1016/j.tpb.2020.07.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 07/19/2020] [Accepted: 07/21/2020] [Indexed: 11/20/2022]
Abstract
During a range expansion, deleterious mutations can "surf" on the colonization front. The resultant decrease in fitness is known as expansion load. An Allee effect is known to reduce the loss of genetic diversity of expanding populations, by changing the nature of the expansion from "pulled" to "pushed". We study the impact of an Allee effect on the formation of an expansion load with a new model, in which individuals have the genetic structure of a Muller's ratchet. A key feature of Muller's ratchet is that the population fatally accumulates deleterious mutations due to the stochastic loss of the fittest individuals, an event called a click of the ratchet. We observe fast clicks of the ratchet at the colonization front owing to small population size, followed by a slow fitness recovery due to migration of fit individuals from the bulk of the population, leading to a transient expansion load. For large population size, we are able to derive quantitative features of the expansion wave, such as the wave speed and the frequency of individuals carrying a given number of mutations. Using simulations, we show that the presence of an Allee effect reduces the rate at which clicks occur at the front, and thus reduces the expansion load.
Collapse
|
42
|
Sinclair EA, Edgeloe JM, Anthony JM, Statton J, Breed MF, Kendrick GA. Variation in reproductive effort, genetic diversity and mating systems across Posidonia australis seagrass meadows in Western Australia. AOB PLANTS 2020; 12:plaa038. [PMID: 32904346 PMCID: PMC7454027 DOI: 10.1093/aobpla/plaa038] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 08/04/2020] [Indexed: 06/11/2023]
Abstract
Populations at the edges of their geographical range tend to have lower genetic diversity, smaller effective population sizes and limited connectivity relative to centre of range populations. Range edge populations are also likely to be better adapted to more extreme conditions for future survival and resilience in warming environments. However, they may also be most at risk of extinction from changing climate. We compare reproductive and genetic data of the temperate seagrass, Posidonia australis on the west coast of Australia. Measures of reproductive effort (flowering and fruit production and seed to ovule ratios) and estimates of genetic diversity and mating patterns (nuclear microsatellite DNA loci) were used to assess sexual reproduction in northern range edge (low latitude, elevated salinities, Shark Bay World Heritage Site) and centre of range (mid-latitude, oceanic salinity, Perth metropolitan waters) meadows in Western Australia. Flower and fruit production were highly variable among meadows and there was no significant relationship between seed to ovule ratio and clonal diversity. However, Shark Bay meadows were two orders of magnitude less fecund than those in Perth metropolitan waters. Shark Bay meadows were characterized by significantly lower levels of genetic diversity and a mixed mating system relative to meadows in Perth metropolitan waters, which had high genetic diversity and a completely outcrossed mating system. The combination of reproductive and genetic data showed overall lower sexual productivity in Shark Bay meadows relative to Perth metropolitan waters. The mixed mating system is likely driven by a combination of local environmental conditions and pollen limitation. These results indicate that seagrass restoration in Shark Bay may benefit from sourcing plant material from multiple reproductive meadows to increase outcrossed pollen availability and seed production for natural recruitment.
Collapse
Affiliation(s)
- Elizabeth A Sinclair
- School of Biological Sciences, University of Western Australia, Crawley, Western Australia, Australia
- Oceans Institute, University of Western Australia, Crawley, Western Australia, Australia
- Kings Park Science, Department of Biodiversity Conservation and Attractions, West Perth, Western Australia, Australia
| | - Jane M Edgeloe
- School of Biological Sciences, University of Western Australia, Crawley, Western Australia, Australia
| | - Janet M Anthony
- School of Biological Sciences, University of Western Australia, Crawley, Western Australia, Australia
- Kings Park Science, Department of Biodiversity Conservation and Attractions, West Perth, Western Australia, Australia
| | - John Statton
- School of Biological Sciences, University of Western Australia, Crawley, Western Australia, Australia
- Oceans Institute, University of Western Australia, Crawley, Western Australia, Australia
| | - Martin F Breed
- College of Science and Engineering, Flinders University, Adelaide, South Australia, Australia
| | - Gary A Kendrick
- School of Biological Sciences, University of Western Australia, Crawley, Western Australia, Australia
- Oceans Institute, University of Western Australia, Crawley, Western Australia, Australia
| |
Collapse
|
43
|
Feutry P, Devloo-Delva F, Tran Lu Y A, Mona S, Gunasekera RM, Johnson G, Pillans RD, Jaccoud D, Kilian A, Morgan DL, Saunders T, Bax NJ, Kyne PM. One panel to rule them all: DArTcap genotyping for population structure, historical demography, and kinship analyses, and its application to a threatened shark. Mol Ecol Resour 2020; 20:1470-1485. [PMID: 32492756 DOI: 10.1111/1755-0998.13204] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 05/26/2020] [Accepted: 05/28/2020] [Indexed: 01/25/2023]
Abstract
With recent advances in sequencing technology, genomic data are changing how important conservation management decisions are made. Applications such as Close-Kin Mark-Recapture demand large amounts of data to estimate population size and structure, and their full potential can only be realised through ongoing improvements in genotyping strategies. Here we introduce DArTcap, a cost-efficient method that combines DArTseq and sequence capture, and illustrate its use in a high resolution population analysis of Glyphis garricki, a rare, poorly known and threatened euryhaline shark. Clustering analyses and spatial distribution of kin pairs from four different regions across northern Australia and one in Papua New Guinea, representing its entire known range, revealed that each region hosts at least one distinct population. Further structuring is likely within Van Diemen Gulf, the region that included the most rivers sampled, suggesting additional population structuring would be found if other rivers were sampled. Coalescent analyses and spatially explicit modelling suggest that G. garricki experienced a recent range expansion during the opening of the Gulf of Carpentaria following the conclusion of the Last Glacial Maximum. The low migration rates between neighbouring populations of a species that is found only in restricted coastal and riverine habitats show the importance of managing each population separately, including careful monitoring of local and remote anthropogenic activities that may affect their environments. Overall we demonstrated how a carefully chosen SNP panel combined with DArTcap can provide highly accurate kinship inference and also support population structure and historical demography analyses, therefore maximising cost-effectiveness.
Collapse
Affiliation(s)
| | - Floriaan Devloo-Delva
- CSIRO Oceans and Atmosphere, Hobart, TAS, Australia.,School of Natural Sciences - Quantitative Marine Science, University of Tasmania, Hobart, TAS, Australia
| | - Adrien Tran Lu Y
- Institut de Systématique, Évolution, Biodiversité (ISYEB), UMR 7205, MNHN, CNRS, EPHE, Sorbonne Université, Paris, France.,EPHE, PSL University, Paris, France
| | - Stefano Mona
- Institut de Systématique, Évolution, Biodiversité (ISYEB), UMR 7205, MNHN, CNRS, EPHE, Sorbonne Université, Paris, France.,EPHE, PSL University, Paris, France.,Laboratoire d'Excellence CORAIL, Papetoai, French Polynesia
| | | | - Grant Johnson
- Department of Primary Industry and Fisheries, Aquatic Resource Research Unit, Darwin, NT, Australia
| | | | - Damian Jaccoud
- Diversity Arrays Technology Pty Ltd, University of Canberra, Bruce, ACT, Australia
| | - Andrzej Kilian
- Diversity Arrays Technology Pty Ltd, University of Canberra, Bruce, ACT, Australia
| | - David L Morgan
- Centre for Sustainable Aquatic Ecosystems, Harry Butler Institute, Murdoch University, Murdoch, WA, Australia
| | - Thor Saunders
- Department of Primary Industry and Fisheries, Aquatic Resource Research Unit, Darwin, NT, Australia
| | - Nicholas J Bax
- CSIRO Oceans and Atmosphere, Hobart, TAS, Australia.,Institute for Marine and Antarctic Science, University of Tasmania, Hobart, TAS, Australia
| | - Peter M Kyne
- Research Institute for the Environment and Livelihoods, Charles Darwin University, Darwin, NT, Australia
| |
Collapse
|
44
|
Koski MH, Galloway LF. Geographic Variation in Floral Color and Reflectance Correlates With Temperature and Colonization History. FRONTIERS IN PLANT SCIENCE 2020; 11:991. [PMID: 32714360 PMCID: PMC7340105 DOI: 10.3389/fpls.2020.00991] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 06/17/2020] [Indexed: 05/12/2023]
Abstract
Petal color variation within species is common and may be molded by abiotic or biotic selection pressures, or neutral population structure. For example, darker flowers may be favored in cooler environments because they absorb more solar radiation, elevating the temperature of reproductive structures. Additionally, flower color may evolve to attract the dominant or most efficient pollinator type in a given population. Here, we evaluate geographic variation in petal coloration across the range of Campanula americana in Eastern North America and test whether color covaries with abiotic factors, the pollination community, and genetic structure established through post-glacial expansion. Consistent with other studies, flowers from cooler, higher latitude populations were less reflective across the UV-NIR spectrum than those from warmer populations. Local temperature explained variation in petal reflectance better than the pollinator community or colonization history. Petal color perceived by trichromatic bee pollinators displayed a strong longitudinal pattern but was unassociated with climatic factors and the pollinator community. Instead, pollinator-perceived color was tightly correlated with the geographic distance from C. americana's glacial refugium. In total, abiotic conditions appear to shape large-scale geographic variation in the intensity of petal reflectance while genetic structure is the strongest driver of pollinator-perceived petal coloration. This study highlights the importance of abiotic factors and historical processes associated with range expansion as major evolutionary forces shaping diversity of flower coloration on large geographic scales.
Collapse
Affiliation(s)
- Matthew H. Koski
- Department of Biological Sciences, Clemson University, Clemson, SC, United States
- Department of Biology, University of Virginia, Charlottesville, VA, United States
| | - Laura F. Galloway
- Department of Biology, University of Virginia, Charlottesville, VA, United States
| |
Collapse
|
45
|
Perrier A, Sánchez-Castro D, Willi Y. Expressed mutational load increases toward the edge of a species' geographic range. Evolution 2020; 74:1711-1723. [PMID: 32538471 DOI: 10.1111/evo.14042] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 05/26/2020] [Accepted: 06/05/2020] [Indexed: 12/14/2022]
Abstract
There is no general explanation for why species have restricted geographic distributions. One hypothesis posits that range expansion or increasing scarcity of suitable habitat results in accumulation of mutational load due to enhanced genetic drift, which constrains population performance toward range limits and further expansion. We tested this hypothesis in the North American plant, Arabidopsis lyrata. We experimentally assessed mutational load by crossing plants of 20 populations from across the entire species range and by raising the offspring of within- and between-population crosses at five common garden sites within and beyond the range. Offspring performance was tracked over three growing seasons. The heterosis effect, depicting expressed mutational load, was increased in populations with heightened genomic estimates of load, longer expansion distance or long-term isolation, and a selfing mating system. The decline in performance of within-population crosses amounted to 80%. Mutation accumulation due to past range expansion and long-term isolation of populations in the area of range margins is therefore a strong determinant of population-mean performance, and the magnitude of effect may be sufficient to cause range limits.
Collapse
Affiliation(s)
- Antoine Perrier
- Department of Environmental Sciences, University of Basel, Basel, 4056, Switzerland
| | - Darío Sánchez-Castro
- Department of Environmental Sciences, University of Basel, Basel, 4056, Switzerland
| | - Yvonne Willi
- Department of Environmental Sciences, University of Basel, Basel, 4056, Switzerland
| |
Collapse
|
46
|
Orsucci M, Milesi P, Hansen J, Girodolle J, Glémin S, Lascoux M. Shift in ecological strategy helps marginal populations of shepherd's purse ( Capsella bursa-pastoris) to overcome a high genetic load. Proc Biol Sci 2020; 287:20200463. [PMID: 32429810 PMCID: PMC7287375 DOI: 10.1098/rspb.2020.0463] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The outcome of species range expansion depends on the interplay of demographic, environmental and genetic factors. Self-fertilizing species usually show a higher invasive ability than outcrossers but selfing and bottlenecks during colonization also lead to an increased genetic load. The relationship between genomic and phenotypic characteristics of expanding populations has, hitherto, rarely been tested experimentally. We analysed how accessions of the shepherd's purse, Capsella bursa-pastoris, from the colonization front or from the core of the natural range performed under increasing density of competitors. First, accessions from the front showed a lower fitness than those from the core. Second, for all accessions, competitor density impacted negatively both vegetative growth and fruit production. However, despite their higher genetic load and lower absolute performances, accessions from the front were less affected by competition than accessions from the core. This seems to be due to phenotypic trade-offs and a shift in phenology that allow accessions from the front to avoid competition.
Collapse
Affiliation(s)
- Marion Orsucci
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - Pascal Milesi
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden.,Science for Life Laboratory, Uppsala, Sweden
| | - Johanna Hansen
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - Johanna Girodolle
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - Sylvain Glémin
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden.,ECOBIO UMR 6553 CNRS University of Rennes 1, Rennes, France
| | - Martin Lascoux
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| |
Collapse
|
47
|
Peischl S, Gilbert KJ. Evolution of Dispersal Can Rescue Populations from Expansion Load. Am Nat 2020; 195:349-360. [DOI: 10.1086/705993] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
48
|
Walden N, Lucek K, Willi Y. Lineage‐specific adaptation to climate involves flowering time in North American
Arabidopsis lyrata. Mol Ecol 2020; 29:1436-1451. [DOI: 10.1111/mec.15338] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 11/16/2019] [Accepted: 12/10/2019] [Indexed: 01/06/2023]
Affiliation(s)
- Nora Walden
- Department of Environmental Sciences University of Basel Basel Switzerland
- Centre for Organismal Studies Heidelberg University of Heidelberg Heidelberg Germany
| | - Kay Lucek
- Department of Environmental Sciences University of Basel Basel Switzerland
| | - Yvonne Willi
- Department of Environmental Sciences University of Basel Basel Switzerland
| |
Collapse
|
49
|
Lucek K, Hohmann N, Willi Y. Postglacial ecotype formation under outcrossing and self-fertilization in Arabidopsis lyrata. Mol Ecol 2019; 28:1043-1055. [PMID: 30719799 DOI: 10.1111/mec.15035] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 01/18/2019] [Accepted: 01/28/2019] [Indexed: 12/01/2022]
Abstract
The formation of ecotypes has been invoked as an important driver of postglacial biodiversity, because many species colonized heterogeneous habitats and experienced divergent selection. Ecotype formation has been predominantly studied in outcrossing taxa, while far less attention has been paid to the implications of mating system shifts. Here, we addressed whether substrate-related ecotypes exist in selfing and outcrossing populations of Arabidopsis lyrata subsp. lyrata and whether the genomic footprint differs between mating systems. The North American subspecies colonized both rocky and sandy habitats during postglacial range expansion and shifted the mating system from predominantly outcrossing to predominantly selfing in a number of regions. We performed an association study on pooled whole-genome sequence data of 20 selfing or outcrossing populations, which suggested genes involved in adaptation to substrate. Motivated by enriched gene ontology terms, we compared root growth between plants from the two substrates in a common environment and found that plants originating from sand grew roots faster and produced more side roots, independent of mating system. Furthermore, single nucleotide polymorphisms associated with substrate-related ecotypes were more clustered among selfing populations. Our study provides evidence for substrate-related ecotypes in A. lyrata and divergence in the genomic footprint between mating systems. The latter is the likely result of selfing populations having experienced divergent selection on larger genomic regions due to higher genome-wide linkage disequilibrium.
Collapse
Affiliation(s)
- Kay Lucek
- Department of Environmental Sciences, University of Basel, Basel, Switzerland
| | - Nora Hohmann
- Department of Environmental Sciences, University of Basel, Basel, Switzerland
| | - Yvonne Willi
- Department of Environmental Sciences, University of Basel, Basel, Switzerland
| |
Collapse
|
50
|
Bélouard N, Paillisson J, Oger A, Besnard A, Petit EJ. Genetic drift during the spread phase of a biological invasion. Mol Ecol 2019; 28:4375-4387. [DOI: 10.1111/mec.15238] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 08/27/2019] [Accepted: 08/27/2019] [Indexed: 12/28/2022]
Affiliation(s)
- Nadège Bélouard
- UMR ECOBIO CNRS Université de Rennes 1 Rennes France
- UMR ESE Ecology and Ecosystem Health INRA, Agrocampus Ouest Rennes France
| | | | - Adrien Oger
- UMR ECOBIO CNRS Université de Rennes 1 Rennes France
| | - Anne‐Laure Besnard
- UMR ESE Ecology and Ecosystem Health INRA, Agrocampus Ouest Rennes France
| | - Eric J. Petit
- UMR ESE Ecology and Ecosystem Health INRA, Agrocampus Ouest Rennes France
| |
Collapse
|