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Judson BJ, Kristjánsson BK, Leblanc CA, Ferguson MM. The role of neutral and adaptive evolutionary processes on patterns of genetic diversity across small cave-dwelling populations of Icelandic Arctic charr ( Salvelinus alpinus). Ecol Evol 2024; 14:e11363. [PMID: 38770124 PMCID: PMC11103641 DOI: 10.1002/ece3.11363] [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: 02/28/2024] [Revised: 04/10/2024] [Accepted: 04/12/2024] [Indexed: 05/22/2024] Open
Abstract
Understanding the adaptability of small populations in the face of environmental change is a central problem in evolutionary biology. Solving this problem is challenging because neutral evolutionary processes that operate on historical and contemporary timescales can override the effects of selection in small populations. We assessed the effects of isolation by colonization (IBC), isolation by dispersal limitation (IBDL) as reflected by a pattern of isolation by distance (IBD), and isolation by adaptation (IBA) and the roles of genetic drift and gene flow on patterns of genetic differentiation among 19 cave-dwelling populations of Icelandic Arctic charr (Salvelinus alpinus). We detected evidence of IBC based on the genetic affinity of nearby cave populations and the genetic relationships between the cave populations and the presumed ancestral population in the lake. A pattern of IBD was evident regardless of whether high-level genetic structuring (IBC) was taken into account. Genetic signatures of bottlenecks and lower genetic diversity in smaller populations indicate the effect of drift. Estimates of gene flow and fish movement suggest that gene flow is limited to nearby populations. In contrast, we found little evidence of IBA as patterns of local ecological and phenotypic variation showed little association with genetic differentiation among populations. Thus, patterns of genetic variation in these small populations likely reflect localized gene flow and genetic drift superimposed onto a larger-scale structure that is largely a result of colonization history. Our simultaneous assessment of the effects of neutral and adaptive processes in a tractable and replicated system has yielded novel insights into the evolution of small populations on both historical and contemporary timescales and over a smaller spatial scale than is typically studied.
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Affiliation(s)
- Braden J. Judson
- Department of Integrative BiologyUniversity of GuelphGuelphOntarioCanada
| | | | | | - Moira M. Ferguson
- Department of Integrative BiologyUniversity of GuelphGuelphOntarioCanada
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2
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Murray CS, Karram M, Bass DJ, Doceti M, Becker D, Nunez JCB, Ratan A, Bergland AO. Balancing selection and the functional effects of shared polymorphism in cryptic Daphnia species. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.16.589693. [PMID: 38659826 PMCID: PMC11042267 DOI: 10.1101/2024.04.16.589693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
The patterns of genetic variation within and between related taxa represent the genetic history of a species. Shared polymorphisms, loci with identical alleles across species, are of unique interest as they may represent cases of ancient selection maintaining functional variation post-speciation. In this study, we investigate the abundance of shared polymorphism in the Daphnia pulex species complex. We test whether shared mutations are consistent with the action of balancing selection or alternative hypotheses such as hybridization, incomplete lineage sorting, or convergent evolution. We analyzed over 2,000 genomes from North American and European D. pulex and several outgroup species to examine the prevalence and distribution of shared alleles between the focal species pair, North American and European D. pulex. We show that while North American and European D. pulex diverged over ten million years ago, they retained tens of thousands of shared alleles. We found that the number of shared polymorphisms between North American and European D. pulex cannot be explained by hybridization or incomplete lineage sorting alone. Instead, we show that most shared polymorphisms could be the product of convergent evolution, that a limited number appear to be old trans-specific polymorphisms, and that balancing selection is affecting young and ancient mutations alike. Finally, we provide evidence that a blue wavelength opsin gene with trans-specific polymorphisms has functional effects on behavior and fitness in the wild. Ultimately, our findings provide insights into the genetic basis of adaptation and the maintenance of genetic diversity between species.
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Affiliation(s)
- Connor S. Murray
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Madison Karram
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - David J. Bass
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Madison Doceti
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Dörthe Becker
- Department of Biology, University of Virginia, Charlottesville, VA, USA
- School of Biosciences, Ecology and Evolutionary Biology, University of Sheffield, Sheffield, UK
| | | | - Aakrosh Ratan
- Center of Public Health Genomics, University of Virginia, Charlottesville, VA, USA
- Department of Public Health Sciences, University of Virginia, Charlottesville, VA, USA
| | - Alan O. Bergland
- Department of Biology, University of Virginia, Charlottesville, VA, USA
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3
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Sethuraman A, Nunziata SO, Jones A, Obrycki J, Weisrock DW. Go west: Population genomics reveals unexpected population fluctuations and little gene flow in Western hemisphere populations of the predatory lady beetle, Hippodamia convergens. Evol Appl 2024; 17:e13631. [PMID: 38283604 PMCID: PMC10810170 DOI: 10.1111/eva.13631] [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: 05/12/2023] [Revised: 11/22/2023] [Accepted: 11/30/2023] [Indexed: 01/30/2024] Open
Abstract
Hippodamia convergens-the convergent lady beetle, has been used extensively in augmentative biological control of aphids, thrips, and whiteflies across its native range in North America, and was introduced into South America in the 1950s. Overwintering H. convergens populations from its native western range in the United States are commercially collected and released across its current range in the eastern USA, with little knowledge of the effectiveness of its augmentative biological control. Here we use a novel ddRADseq-based SNP/haplotype discovery approach to estimate its range-wide population diversity, differentiation, and recent evolutionary history. Our results indicate (1) significant population differentiation among eastern USA, western USA, and South American populations of H. convergens, with (2) little to no detectable recent admixture between them, despite repeated population augmentation, and (3) continued recent population size expansion across its range. These results contradict previous findings using microsatellite markers. In light of these new findings, the implications for the effectiveness of augmentative biological control using H. convergens are discussed. Additionally, because quantifying the non-target effects of augmentative biological control is a difficult problem in migratory beetles, our results could serve as a cornerstone in improving and predicting the efficacy of future releases of H. convergens across its range.
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Affiliation(s)
- Arun Sethuraman
- Department of BiologySan Diego State UniversitySan DiegoCaliforniaUSA
| | - Schyler O. Nunziata
- Department of BiologyUniversity of KentuckyLexingtonKentuckyUSA
- Present address:
United States Department of AgricultureWashingtonDCUSA
| | - Angela Jones
- Department of BiologyUniversity of KentuckyLexingtonKentuckyUSA
- Present address:
Duke UniversityDurhamNorth CarolinaUSA
| | - John Obrycki
- Department of EntomologyUniversity of KentuckyLexingtonKentuckyUSA
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4
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Nigenda-Morales SF, Lin M, Nuñez-Valencia PG, Kyriazis CC, Beichman AC, Robinson JA, Ragsdale AP, Urbán R J, Archer FI, Viloria-Gómora L, Pérez-Álvarez MJ, Poulin E, Lohmueller KE, Moreno-Estrada A, Wayne RK. The genomic footprint of whaling and isolation in fin whale populations. Nat Commun 2023; 14:5465. [PMID: 37699896 PMCID: PMC10497599 DOI: 10.1038/s41467-023-40052-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 07/10/2023] [Indexed: 09/14/2023] Open
Abstract
Twentieth century industrial whaling pushed several species to the brink of extinction, with fin whales being the most impacted. However, a small, resident population in the Gulf of California was not targeted by whaling. Here, we analyzed 50 whole-genomes from the Eastern North Pacific (ENP) and Gulf of California (GOC) fin whale populations to investigate their demographic history and the genomic effects of natural and human-induced bottlenecks. We show that the two populations diverged ~16,000 years ago, after which the ENP population expanded and then suffered a 99% reduction in effective size during the whaling period. In contrast, the GOC population remained small and isolated, receiving less than one migrant per generation. However, this low level of migration has been crucial for maintaining its viability. Our study exposes the severity of whaling, emphasizes the importance of migration, and demonstrates the use of genome-based analyses and simulations to inform conservation strategies.
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Affiliation(s)
- Sergio F Nigenda-Morales
- Advanced Genomics Unit, National Laboratory of Genomics for Biodiversity (Langebio), Center for Research and Advanced Studies (Cinvestav), Irapuato, Guanajuato, 36824, Mexico.
- Department of Biological Sciences, California State University San Marcos, San Marcos, CA, 92096, USA.
| | - Meixi Lin
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, CA, 90095, USA.
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA, 94305, USA.
| | - Paulina G Nuñez-Valencia
- Advanced Genomics Unit, National Laboratory of Genomics for Biodiversity (Langebio), Center for Research and Advanced Studies (Cinvestav), Irapuato, Guanajuato, 36824, Mexico
- Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, México
| | - Christopher C Kyriazis
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Annabel C Beichman
- Department of Genome Sciences, University of Washington, Seattle, WA, 98195, USA
| | - Jacqueline A Robinson
- Institute for Human Genetics, University of California, San Francisco (UCSF), San Francisco, CA, 94143, USA
| | - Aaron P Ragsdale
- Advanced Genomics Unit, National Laboratory of Genomics for Biodiversity (Langebio), Center for Research and Advanced Studies (Cinvestav), Irapuato, Guanajuato, 36824, Mexico
- Department of Integrative Biology, University of Wisconsin, Madison, WI, 53706, USA
| | - Jorge Urbán R
- Departamento de Ciencias Marinas y Costeras, Universidad Autónoma de Baja California Sur (UABCS), La Paz, Baja California Sur, Mexico
| | - Frederick I Archer
- Marine Mammal and Turtle Division, Southwest Fisheries Science Center, La Jolla, CA, 92037, USA
| | - Lorena Viloria-Gómora
- Departamento de Ciencias Marinas y Costeras, Universidad Autónoma de Baja California Sur (UABCS), La Paz, Baja California Sur, Mexico
| | - María José Pérez-Álvarez
- Escuela de Medicina Veterinaria, Facultad de Medicina y Ciencias de la Salud, Universidad Mayor, Santiago, Chile
- Millennium Institute Biodiversity of Antarctic and Subantarctic Ecosystems (BASE), Universidad de Chile, Santiago, Chile
| | - Elie Poulin
- Millennium Institute Biodiversity of Antarctic and Subantarctic Ecosystems (BASE), Universidad de Chile, Santiago, Chile
| | - Kirk E Lohmueller
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, CA, 90095, USA.
- Interdepartmental Program in Bioinformatics, University of California, Los Angeles, CA, 90095, USA.
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, CA, USA.
| | - Andrés Moreno-Estrada
- Advanced Genomics Unit, National Laboratory of Genomics for Biodiversity (Langebio), Center for Research and Advanced Studies (Cinvestav), Irapuato, Guanajuato, 36824, Mexico.
| | - Robert K Wayne
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, CA, 90095, USA
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5
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Abstract
Insects constitute vital components of ecosystems. There is alarming evidence for global declines in insect species diversity, abundance, and biomass caused by anthropogenic drivers such as habitat degradation or loss, agricultural practices, climate change, and environmental pollution. This raises important concerns about human food security and ecosystem functionality and calls for more research to assess insect population trends and identify threatened species and the causes of declines to inform conservation strategies. Analysis of genetic diversity is a powerful tool to address these goals, but so far animal conservation genetics research has focused strongly on endangered vertebrates, devoting less attention to invertebrates, such as insects, that constitute most biodiversity. Insects' shorter generation times and larger population sizes likely necessitate different analytical methods and management strategies. The availability of high-quality reference genome assemblies enables population genomics to address several key issues. These include precise inference of past demographic fluctuations and recent declines, measurement of genetic load levels, delineation of evolutionarily significant units and cryptic species, and analysis of genetic adaptation to stressors. This enables identification of populations that are particularly vulnerable to future threats, considering their potential to adapt and evolve. We review the application of population genomics to insect conservation and the outlook for averting insect declines.
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Affiliation(s)
- Matthew T Webster
- Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden;
| | - Alexis Beaurepaire
- Institute of Bee Health, Vetsuisse Faculty, University of Bern, Bern, Switzerland.,Agroscope, Swiss Bee Research Centre, Bern, Switzerland
| | - Peter Neumann
- Institute of Bee Health, Vetsuisse Faculty, University of Bern, Bern, Switzerland.,Agroscope, Swiss Bee Research Centre, Bern, Switzerland
| | - Eckart Stolle
- Leibniz Institute for the Analysis of Biodiversity Change, Museum Koenig, Bonn, Germany
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6
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Hoey JA, Able KW, Pinsky ML. Genetic decline and recovery of a demographically rebuilt fishery species. Mol Ecol 2022; 31:5684-5698. [PMID: 36114805 PMCID: PMC9828022 DOI: 10.1111/mec.16697] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 09/09/2022] [Accepted: 09/15/2022] [Indexed: 01/13/2023]
Abstract
The demographic history of a population is important for conservation and evolution, but this history is unknown for many populations. Methods that use genomic data have been developed to infer demography, but they can be challenging to implement and interpret, particularly for large populations. Thus, understanding if and when genetic estimates of demography correspond to true population history is important for assessing the performance of these genetic methods. Here, we used double-digest restriction-site associated DNA (ddRAD) sequencing data from archived collections of larval summer flounder (Paralichthys dentatus, n = 279) from three cohorts (1994-1995, 1997-1998 and 2008-2009) along the U.S. East coast to examine how contemporary effective population size and genetic diversity responded to changes in abundance in a natural population. Despite little to no detectable change in genetic diversity, coalescent-based demographic modelling from site frequency spectra revealed that summer flounder effective population size declined dramatically in the early 1980s. The timing and direction of change corresponded well with the observed decline in spawning stock census abundance in the late 1980s from independent fish surveys. Census abundance subsequently recovered and achieved the prebottleneck size. Effective population size also grew following the bottleneck. Our results for summer flounder demonstrate that genetic sampling and site frequency spectra can be useful for detecting population dynamics, even in species with large effective sizes.
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Affiliation(s)
- Jennifer A. Hoey
- Ecology, Evolution, & Natural ResourcesRutgers UniversityNew BrunswickNew JerseyUSA,Institute for Biodiversity Science and SustainabilityCalifornia Academy of SciencesSan FranciscoCaliforniaUSA
| | - Kenneth W. Able
- Marine Field Station, Department of Marine and Coastal Sciences, Rutgers UniversityTuckertonNew JerseyUSA
| | - Malin L. Pinsky
- Ecology, Evolution, & Natural ResourcesRutgers UniversityNew BrunswickNew JerseyUSA
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7
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Friis G, Atwell JW, Fudickar AM, Greives TJ, Yeh PJ, Price TD, Ketterson ED, Milá B. Rapid evolutionary divergence of a songbird population following recent colonization of an urban area. Mol Ecol 2022; 31:2625-2643. [DOI: 10.1111/mec.16422] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 01/14/2022] [Accepted: 03/01/2022] [Indexed: 11/27/2022]
Affiliation(s)
- Guillermo Friis
- National Museum of Natural Sciences Department of Biodiversity and Evolutionary Biology Spanish National Research Council (CSIC) Madrid 28006 Spain
| | | | - Adam M. Fudickar
- Department of Biology Indiana University Bloomington IN 47405 USA
| | - Timothy J. Greives
- Department of Biological Sciences North Dakota State University Fargo ND 58105 USA
| | - Pamela J. Yeh
- Department of Ecology and Evolutionary Biology University of California Los Angeles Los Angeles CA 90095 USA
| | - Trevor D. Price
- Department of Ecology and Evolution University of Chicago Chicago IL 60637 USA
| | | | - Borja Milá
- National Museum of Natural Sciences Department of Biodiversity and Evolutionary Biology Spanish National Research Council (CSIC) Madrid 28006 Spain
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8
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Liu X, Glémin S, Karrenberg S. Evolution of putative barrier loci at an intermediate stage of speciation with gene flow in campions (Silene). Mol Ecol 2020; 29:3511-3525. [PMID: 32740990 PMCID: PMC7540528 DOI: 10.1111/mec.15571] [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] [Received: 07/15/2019] [Revised: 07/09/2020] [Accepted: 07/16/2020] [Indexed: 12/22/2022]
Abstract
Understanding the origin of new species is a central goal in evolutionary biology. Diverging lineages often evolve highly heterogeneous patterns of genetic differentiation; however, the underlying mechanisms are not well understood. We investigated evolutionary processes governing genetic differentiation between the hybridizing campions Silene dioica (L.) Clairv. and S. latifolia Poiret. Demographic modelling indicated that the two species diverged with gene flow. The best‐supported scenario with heterogeneity in both migration rate and effective population size suggested that a small proportion of the loci evolved without gene flow. Differentiation (FST) and sequence divergence (dXY) were correlated and both tended to peak in the middle of most linkage groups, consistent with reduced gene flow at highly differentiated loci. Highly differentiated loci further exhibited signatures of selection. In between‐species population pairs, isolation by distance was stronger for genomic regions with low between‐species differentiation than for highly differentiated regions that may contain barrier loci. Moreover, differentiation landscapes within and between species were only weakly correlated, suggesting that linked selection due to shared recombination and gene density landscapes is not the dominant determinant of genetic differentiation in these lineages. Instead, our results suggest that divergent selection shaped the genomic landscape of differentiation between the two Silene species, consistent with predictions for speciation in the face of gene flow.
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Affiliation(s)
- Xiaodong Liu
- 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.,UMR CNRS 6553 ECOBIO, Université de Rennes I, Rennes Cedex, France
| | - Sophie Karrenberg
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
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9
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Sendell-Price AT, Ruegg KC, Clegg SM. Rapid morphological divergence following a human-mediated introduction: the role of drift and directional selection. Heredity (Edinb) 2020; 124:535-549. [PMID: 32080374 PMCID: PMC7080774 DOI: 10.1038/s41437-020-0298-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 01/31/2020] [Accepted: 02/03/2020] [Indexed: 01/25/2023] Open
Abstract
Theory predicts that when populations are established by few individuals, random founder effects can facilitate rapid phenotypic divergence even in the absence of selective processes. However, empirical evidence from historically documented colonisations suggest that, in most cases, drift alone is not sufficient to explain the rate of morphological divergence. Here, using the human-mediated introduction of the silvereye (Zosterops lateralis) to French Polynesia, which represents a potentially extreme example of population founding, we reassess the potential for morphological shifts to arise via drift alone. Despite only 80 years of separation from their New Zealand ancestors, French Polynesian silvereyes displayed significant changes in body and bill size and shape, most of which could be accounted for by drift, without the need to invoke selection. However, signatures of selection at genes previously identified as candidates for bill size and body shape differences in a range of bird species, also suggests a role for selective processes in driving morphological shifts within this population. Twenty-four SNPs in our RAD-Seq dataset were also found to be strongly associated with phenotypic variation. Hence, even under population founding extremes, when it is difficult to reject drift as the sole mechanism based on rate tests of phenotypic shifts, the additional role of divergent natural selection in novel environments can be revealed at the level of the genome.
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Affiliation(s)
- Ashley T Sendell-Price
- Department of Zoology, Edward Grey Institute of Field Ornithology, University of Oxford, Oxford, OX1 3PS, UK.
| | - Kristen C Ruegg
- Department of Zoology, Edward Grey Institute of Field Ornithology, University of Oxford, Oxford, OX1 3PS, UK
- Department of Biology, Colorado State University, Fort Collins, CO, USA
- Center for Tropical Research, Institute of the Environment and Sustainability, University of California, Los Angeles, Los Angeles, CA, USA
| | - Sonya M Clegg
- Department of Zoology, Edward Grey Institute of Field Ornithology, University of Oxford, Oxford, OX1 3PS, UK
- Environmental Futures Research Institute, Griffith University, Queensland, 4111, Australia
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10
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Noskova E, Ulyantsev V, Koepfli KP, O’Brien SJ, Dobrynin P. GADMA: Genetic algorithm for inferring demographic history of multiple populations from allele frequency spectrum data. Gigascience 2020; 9:giaa005. [PMID: 32112099 PMCID: PMC7049072 DOI: 10.1093/gigascience/giaa005] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2019] [Revised: 09/16/2019] [Accepted: 01/13/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND The demographic history of any population is imprinted in the genomes of the individuals that make up the population. One of the most popular and convenient representations of genetic information is the allele frequency spectrum (AFS), the distribution of allele frequencies in populations. The joint AFS is commonly used to reconstruct the demographic history of multiple populations, and several methods based on diffusion approximation (e.g., ∂a∂i) and ordinary differential equations (e.g., moments) have been developed and applied for demographic inference. These methods provide an opportunity to simulate AFS under a variety of researcher-specified demographic models and to estimate the best model and associated parameters using likelihood-based local optimizations. However, there are no known algorithms to perform global searches of demographic models with a given AFS. RESULTS Here, we introduce a new method that implements a global search using a genetic algorithm for the automatic and unsupervised inference of demographic history from joint AFS data. Our method is implemented in the software GADMA (Genetic Algorithm for Demographic Model Analysis, https://github.com/ctlab/GADMA). CONCLUSIONS We demonstrate the performance of GADMA by applying it to sequence data from humans and non-model organisms and show that it is able to automatically infer a demographic model close to or even better than the one that was previously obtained manually. Moreover, GADMA is able to infer multiple demographic models at different local optima close to the global one, providing a larger set of possible scenarios to further explore demographic history.
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Affiliation(s)
- Ekaterina Noskova
- Computer Technologies Laboratory, ITMO University, 49 Kronverkskiy Pr., St. Petersburg 197101, Russian Federation
| | - Vladimir Ulyantsev
- Computer Technologies Laboratory, ITMO University, 49 Kronverkskiy Pr., St. Petersburg 197101, Russian Federation
| | - Klaus-Peter Koepfli
- Computer Technologies Laboratory, ITMO University, 49 Kronverkskiy Pr., St. Petersburg 197101, Russian Federation
- Smithsonian Conservation Biology Institute, Center for Species Survival, National Zoological Park, 3001 Connecticut Ave., NW Washington, D.C. 20008, USA
| | - Stephen J O’Brien
- Computer Technologies Laboratory, ITMO University, 49 Kronverkskiy Pr., St. Petersburg 197101, Russian Federation
- Guy Harvey Oceanographic Center, Nova Southeastern University Ft. Lauderdale, 8000 North Ocean Drive, Ft. Lauderdale, Florida 33004, USA
| | - Pavel Dobrynin
- Computer Technologies Laboratory, ITMO University, 49 Kronverkskiy Pr., St. Petersburg 197101, Russian Federation
- Smithsonian Conservation Biology Institute, Center for Species Survival, National Zoological Park, 3001 Connecticut Ave., NW Washington, D.C. 20008, USA
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11
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Garot E, Joët T, Combes MC, Severac D, Lashermes P. Plant population dynamics on oceanic islands during the Late Quaternary climate changes: genetic evidence from a tree species (Coffea mauritiana) in Reunion Island. THE NEW PHYTOLOGIST 2019; 224:974-986. [PMID: 31291469 DOI: 10.1111/nph.16052] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Accepted: 07/04/2019] [Indexed: 06/09/2023]
Abstract
Past climatic fluctuations have played a major role in shaping the current plant biodiversity. Although harbouring an exceptional biota, oceanic islands have received little attention in studies on species demographic history and past vegetation patterns. We investigated the impact of past climatic changes on the effective population size of a tree (Coffea mauritiana) that is endemic to Reunion Island, located in the south-western Indian Ocean (SWIO). Demographic changes were inferred using summary statistics calculated from genomic data. Using ecological niche modelling and the current distribution of genetic diversity, the paleodistribution of the species was also assessed. A reduction in the effective population size of C. mauritiana during the last glaciation maximum was inferred. The distribution of the species was reduced on the western side of the island, due to low rainfall. It appeared that a major reduction in rainfall and a slight temperature decrease prevailed in the SWIO. Our findings indicated that analyses on the current patterns of intraspecific genetic variations can efficiently contribute to past climatic changes characterisation in remote islands. Identifying area with higher resilience in oceanic islands could provide guidance in forest management and conservation faced to the global climate change.
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Affiliation(s)
- Edith Garot
- IRD, University of Montpellier, DIADE, 34394, Montpellier, France
| | - Thierry Joët
- IRD, University of Montpellier, DIADE, 34394, Montpellier, France
| | | | - Dany Severac
- MGX, University of Montpellier, CNRS, INSERM, 34095, Montpellier, France
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12
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Huang JP. Holocene Population Decline and Conservation Implication for the Western Hercules Beetle, Dynastes grantii (Coleoptera, Scarabaeidae). J Hered 2019; 110:629-637. [DOI: 10.1093/jhered/esz036] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2019] [Accepted: 05/25/2019] [Indexed: 12/17/2022] Open
Abstract
Abstract
The Western Hercules beetle (Dynastes grantii) is endemic to the highland forest habitats of southwestern United States and northern Mexico. The habitats harbor many endemic species, but are being threatened by rapid climate change and urban development. In this study, the genetic structure of D. grantii populations from southwestern United States was investigated. Specifically, genomic data from double-digest restriction-site-associated DNA sequencing libraries were utilized to test whether geographically distant populations from the Mogollon Rim (Arizona [N = 12 individuals] and New Mexico [N = 10 individuals]) are genetically structured. The study also estimated the effective population size of the Mogollon Rim populations based on genetic diversity. The results indicated that the 2 geographic populations from the Mogollon Rim were not genetically structured. A population size reduction was detected since the end of the last glacial period, which coincided with a reduction of forest habitat in the study area. The results implied that the connectivity and the size of highland forest habitats in the Mogollon Rim could have been the major factors shaping the population genetic structure and demographic history of D. grantii. The Western Hercules beetle could be a useful flagship species for local natural history education and to promote the conservation of highland forest habitats.
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Affiliation(s)
- Jen-Pan Huang
- Biodiversity Research Center, Academia Sinica, Nankang, Taipei, Taiwan
- Integrative Research Center, The Field Museum of Natural History, Chicago, IL
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13
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Beichman AC, Huerta-Sanchez E, Lohmueller KE. Using Genomic Data to Infer Historic Population Dynamics of Nonmodel Organisms. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2018. [DOI: 10.1146/annurev-ecolsys-110617-062431] [Citation(s) in RCA: 89] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Genome sequence data are now being routinely obtained from many nonmodel organisms. These data contain a wealth of information about the demographic history of the populations from which they originate. Many sophisticated statistical inference procedures have been developed to infer the demographic history of populations from this type of genomic data. In this review, we discuss the different statistical methods available for inference of demography, providing an overview of the underlying theory and logic behind each approach. We also discuss the types of data required and the pros and cons of each method. We then discuss how these methods have been applied to a variety of nonmodel organisms. We conclude by presenting some recommendations for researchers looking to use genomic data to infer demographic history.
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Affiliation(s)
- Annabel C. Beichman
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, California 90095, USA
| | - Emilia Huerta-Sanchez
- Department of Molecular and Cell Biology, University of California, Merced, California 95343, USA
- Current affiliation: Department of Ecology and Evolutionary Biology, Brown University, Providence, Rhode Island 02912, USA
| | - Kirk E. Lohmueller
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, California 90095, USA
- Interdepartmental Program in Bioinformatics and Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, California 90095, USA
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14
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Fraïsse C, Roux C, Gagnaire PA, Romiguier J, Faivre N, Welch JJ, Bierne N. The divergence history of European blue mussel species reconstructed from Approximate Bayesian Computation: the effects of sequencing techniques and sampling strategies. PeerJ 2018; 6:e5198. [PMID: 30083438 PMCID: PMC6071616 DOI: 10.7717/peerj.5198] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 06/19/2018] [Indexed: 01/25/2023] Open
Abstract
Genome-scale diversity data are increasingly available in a variety of biological systems, and can be used to reconstruct the past evolutionary history of species divergence. However, extracting the full demographic information from these data is not trivial, and requires inferential methods that account for the diversity of coalescent histories throughout the genome. Here, we evaluate the potential and limitations of one such approach. We reexamine a well-known system of mussel sister species, using the joint site frequency spectrum (jSFS) of synonymous mutations computed either from exome capture or RNA-seq, in an Approximate Bayesian Computation (ABC) framework. We first assess the best sampling strategy (number of: individuals, loci, and bins in the jSFS), and show that model selection is robust to variation in the number of individuals and loci. In contrast, different binning choices when summarizing the jSFS, strongly affect the results: including classes of low and high frequency shared polymorphisms can more effectively reveal recent migration events. We then take advantage of the flexibility of ABC to compare more realistic models of speciation, including variation in migration rates through time (i.e., periodic connectivity) and across genes (i.e., genome-wide heterogeneity in migration rates). We show that these models were consistently selected as the most probable, suggesting that mussels have experienced a complex history of gene flow during divergence and that the species boundary is semi-permeable. Our work provides a comprehensive evaluation of ABC demographic inference in mussels based on the coding jSFS, and supplies guidelines for employing different sequencing techniques and sampling strategies. We emphasize, perhaps surprisingly, that inferences are less limited by the volume of data, than by the way in which they are analyzed.
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Affiliation(s)
- Christelle Fraïsse
- Institut des Sciences de l’Evolution UMR5554, University Montpellier, CNRS, IRD, EPHE, Montpellier, France
- Department of Genetics, University of Cambridge, Cambridge, UK
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Camille Roux
- Université de Lille, Unité Evo-Eco-Paléo (EEP), UMR 8198, Villeneuve d’Ascq, France
| | - Pierre-Alexandre Gagnaire
- Institut des Sciences de l’Evolution UMR5554, University Montpellier, CNRS, IRD, EPHE, Montpellier, France
| | - Jonathan Romiguier
- Institut des Sciences de l’Evolution UMR5554, University Montpellier, CNRS, IRD, EPHE, Montpellier, France
| | - Nicolas Faivre
- Institut des Sciences de l’Evolution UMR5554, University Montpellier, CNRS, IRD, EPHE, Montpellier, France
- Department of Genetics, University of Cambridge, Cambridge, UK
| | - John J. Welch
- Department of Genetics, University of Cambridge, Cambridge, UK
| | - Nicolas Bierne
- Institut des Sciences de l’Evolution UMR5554, University Montpellier, CNRS, IRD, EPHE, Montpellier, France
- Department of Genetics, University of Cambridge, Cambridge, UK
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15
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Parobek CM, Parr JB, Brazeau NF, Lon C, Chaorattanakawee S, Gosi P, Barnett EJ, Norris LD, Meshnick SR, Spring MD, Lanteri CA, Bailey JA, Saunders DL, Lin JT, Juliano JJ. Partner-Drug Resistance and Population Substructuring of Artemisinin-Resistant Plasmodium falciparum in Cambodia. Genome Biol Evol 2018; 9:1673-1686. [PMID: 28854635 PMCID: PMC5522704 DOI: 10.1093/gbe/evx126] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/08/2017] [Indexed: 12/13/2022] Open
Abstract
Plasmodium falciparum in western Cambodia has developed resistance to artemisinin and its partner drugs, causing frequent treatment failure. Understanding this evolution can inform the deployment of new therapies. We investigated the genetic architecture of 78 falciparum isolates using whole-genome sequencing, correlating results to in vivo and ex vivo drug resistance and exploring the relationship between population structure, demographic history, and partner drug resistance. Principle component analysis, network analysis and demographic inference identified a diverse central population with three clusters of clonally expanding parasite populations, each associated with specific K13 artemisinin resistance alleles and partner drug resistance profiles which were consistent with the sequential deployment of artemisinin combination therapies in the region. One cluster displayed ex vivo piperaquine resistance and mefloquine sensitivity with a high rate of in vivo failure of dihydroartemisinin-piperaquine. Another cluster displayed ex vivo mefloquine resistance and piperaquine sensitivity with high in vivo efficacy of dihydroartemisinin-piperaquine. The final cluster was clonal and displayed intermediate sensitivity to both drugs. Variations in recently described piperaquine resistance markers did not explain the difference in mean IC90 or clinical failures between the high and intermediate piperaquine resistance groups, suggesting additional loci may be involved in resistance. The results highlight an important role for partner drug resistance in shaping the P. falciparum genetic landscape in Southeast Asia and suggest that further work is needed to evaluate for other mutations that drive piperaquine resistance.
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Affiliation(s)
- Christian M Parobek
- Curriculum in Genetics and Molecular Biology, School of Medicine, University of North Carolina, Chapel Hill
| | - Jonathan B Parr
- Division of Infectious Diseases, University of North Carolina, Chapel Hill
| | - Nicholas F Brazeau
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill
| | - Chanthap Lon
- Department of Immunology and Medicine, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Suwanna Chaorattanakawee
- Department of Immunology and Medicine, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Panita Gosi
- Department of Immunology and Medicine, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Eric J Barnett
- School of Medicine, Upstate Medical University, State University of New York, Syracuse
| | - Lauren D Norris
- Division of Infectious Diseases, University of North Carolina, Chapel Hill
| | - Steven R Meshnick
- Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill
| | - Michele D Spring
- Department of Immunology and Medicine, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Charlotte A Lanteri
- Department of Immunology and Medicine, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Jeffrey A Bailey
- Program in Bioinformatics and Integrative Biology, Division of Transfusion Medicine, University of Massachusetts Medical School
| | - David L Saunders
- Department of Immunology and Medicine, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Jessica T Lin
- Division of Infectious Diseases, University of North Carolina, Chapel Hill
| | - Jonathan J Juliano
- Curriculum in Genetics and Molecular Biology, School of Medicine, University of North Carolina, Chapel Hill.,Division of Infectious Diseases, University of North Carolina, Chapel Hill.,Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina, Chapel Hill
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16
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Nunziata SO, Weisrock DW. Estimation of contemporary effective population size and population declines using RAD sequence data. Heredity (Edinb) 2017; 120:196-207. [PMID: 29269932 DOI: 10.1038/s41437-017-0037-y] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 10/12/2017] [Accepted: 11/09/2017] [Indexed: 12/12/2022] Open
Abstract
Large genomic data sets generated with restriction site-associated DNA sequencing (RADseq), in combination with demographic inference methods, are improving our ability to gain insights into the population history of species. We used a simulation approach to examine the potential for RADseq data sets to accurately estimate effective population size (N e) over the course of stable and declining population trends, and we compare the ability of two methods of analysis to accurately distinguish stable from steadily declining populations over a contemporary time scale (20 generations). Using a linkage disequilibrium-based analysis, individual sampling (i.e., n ≥ 30) had the greatest effect on N e estimation and the detection of population size declines, with declines reliably detected across scenarios ~10 generations after they began. Coalescent-based inference required fewer sampled individuals (i.e., n = 15), and instead was most influenced by the size of the SNP data set, with 25,000-50,000 SNPs required for accurate detection of population trends and at least 20 generations after decline began. The number of samples available and targeted number of RADseq loci are important criteria when choosing between these methods. Neither method suffered any apparent bias due to the effects of allele dropout typical of RAD data. With an understanding of the limitations and biases of these approaches, researchers can make more informed decisions when designing their sampling and analyses. Overall, our results reveal that demographic inference using RADseq data can be successfully applied to infer recent population size change and may be an important tool for population monitoring and conservation biology.
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Affiliation(s)
- Schyler O Nunziata
- Department of Biology, University of Kentucky, Lexington, KY, 40506, USA.
| | - David W Weisrock
- Department of Biology, University of Kentucky, Lexington, KY, 40506, USA
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17
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Leblois R, Gautier M, Rohfritsch A, Foucaud J, Burban C, Galan M, Loiseau A, Sauné L, Branco M, Gharbi K, Vitalis R, Kerdelhué C. Deciphering the demographic history of allochronic differentiation in the pine processionary moth Thaumetopoea pityocampa. Mol Ecol 2017; 27:264-278. [DOI: 10.1111/mec.14411] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 10/17/2017] [Accepted: 10/25/2017] [Indexed: 01/01/2023]
Affiliation(s)
- R. Leblois
- CBGP, INRA, CIRAD, IRD, Montpellier SupAgro, Univ. Montpellier; Montferrier sur Lez Cedex France
- Institut de Biologie Computationnelle (IBC); Université de Montpellier; Montpellier France
| | - M. Gautier
- CBGP, INRA, CIRAD, IRD, Montpellier SupAgro, Univ. Montpellier; Montferrier sur Lez Cedex France
- Institut de Biologie Computationnelle (IBC); Université de Montpellier; Montpellier France
| | - A. Rohfritsch
- CBGP, INRA, CIRAD, IRD, Montpellier SupAgro, Univ. Montpellier; Montferrier sur Lez Cedex France
| | - J. Foucaud
- CBGP, INRA, CIRAD, IRD, Montpellier SupAgro, Univ. Montpellier; Montferrier sur Lez Cedex France
| | - C. Burban
- INRA, UMR1202 BIOGECO (INRA - Université de Bordeaux); Cestas Cedex France
| | - M. Galan
- CBGP, INRA, CIRAD, IRD, Montpellier SupAgro, Univ. Montpellier; Montferrier sur Lez Cedex France
| | - A. Loiseau
- CBGP, INRA, CIRAD, IRD, Montpellier SupAgro, Univ. Montpellier; Montferrier sur Lez Cedex France
| | - L. Sauné
- CBGP, INRA, CIRAD, IRD, Montpellier SupAgro, Univ. Montpellier; Montferrier sur Lez Cedex France
| | - M. Branco
- Centro de Estudos Florestais (CEF); Instituto Superior de Agronomia (ISA); University of Lisbon; Lisbon Portugal
| | - K. Gharbi
- Edinburgh Genomics; School of Biological Sciences; University of Edinburgh; Edinburgh UK
| | - R. Vitalis
- CBGP, INRA, CIRAD, IRD, Montpellier SupAgro, Univ. Montpellier; Montferrier sur Lez Cedex France
- Institut de Biologie Computationnelle (IBC); Université de Montpellier; Montpellier France
| | - C. Kerdelhué
- CBGP, INRA, CIRAD, IRD, Montpellier SupAgro, Univ. Montpellier; Montferrier sur Lez Cedex France
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18
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Genomic data reveal a loss of diversity in two species of tuco-tucos (genus Ctenomys) following a volcanic eruption. Sci Rep 2017; 7:16227. [PMID: 29176629 PMCID: PMC5701162 DOI: 10.1038/s41598-017-16430-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 11/03/2017] [Indexed: 11/28/2022] Open
Abstract
Marked reductions in population size can trigger corresponding declines in genetic variation. Understanding the precise genetic consequences of such reductions, however, is often challenging due to the absence of robust pre- and post-reduction datasets. Here, we use heterochronous genomic data from samples obtained before and immediately after the 2011 eruption of the Puyehue-Cordón Caulle volcanic complex in Patagonia to explore the genetic impacts of this event on two parapatric species of rodents, the colonial tuco-tuco (Ctenomys sociabilis) and the Patagonian tuco-tuco (C. haigi). Previous analyses using microsatellites revealed no post-eruption changes in genetic variation in C. haigi, but an unexpected increase in variation in C. sociabilis. To explore this outcome further, we used targeted gene capture to sequence over 2,000 putatively neutral regions for both species. Our data revealed that, contrary to the microsatellite analyses, the eruption was associated with a small but significant decrease in genetic variation in both species. We suggest that genome-level analyses provide greater power than traditional molecular markers to detect the genetic consequences of population size changes, particularly changes that are recent, short-term, or modest in size. Consequently, genomic analyses promise to generate important new insights into the effects of specific environmental events on demography and genetic variation.
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19
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Comparison of Single Genome and Allele Frequency Data Reveals Discordant Demographic Histories. G3-GENES GENOMES GENETICS 2017; 7:3605-3620. [PMID: 28893846 PMCID: PMC5677151 DOI: 10.1534/g3.117.300259] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Inference of demographic history from genetic data is a primary goal of population genetics of model and nonmodel organisms. Whole genome-based approaches such as the pairwise/multiple sequentially Markovian coalescent methods use genomic data from one to four individuals to infer the demographic history of an entire population, while site frequency spectrum (SFS)-based methods use the distribution of allele frequencies in a sample to reconstruct the same historical events. Although both methods are extensively used in empirical studies and perform well on data simulated under simple models, there have been only limited comparisons of them in more complex and realistic settings. Here we use published demographic models based on data from three human populations (Yoruba, descendants of northwest-Europeans, and Han Chinese) as an empirical test case to study the behavior of both inference procedures. We find that several of the demographic histories inferred by the whole genome-based methods do not predict the genome-wide distribution of heterozygosity, nor do they predict the empirical SFS. However, using simulated data, we also find that the whole genome methods can reconstruct the complex demographic models inferred by SFS-based methods, suggesting that the discordant patterns of genetic variation are not attributable to a lack of statistical power, but may reflect unmodeled complexities in the underlying demography. More generally, our findings indicate that demographic inference from a small number of genomes, routine in genomic studies of nonmodel organisms, should be interpreted cautiously, as these models cannot recapitulate other summaries of the data.
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20
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Neethiraj R, Hornett EA, Hill JA, Wheat CW. Investigating the genomic basis of discrete phenotypes using a Pool-Seq-only approach: New insights into the genetics underlying colour variation in diverse taxa. Mol Ecol 2017; 26:4990-5002. [PMID: 28614599 DOI: 10.1111/mec.14205] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 05/09/2017] [Accepted: 05/15/2017] [Indexed: 12/11/2022]
Abstract
While large-scale genomic approaches are increasingly revealing the genetic basis of polymorphic phenotypes such as colour morphs, such approaches are almost exclusively conducted in species with high-quality genomes and annotations. Here, we use Pool-Seq data for both genome assembly and SNP frequency estimation, followed by scanning for FST outliers to identify divergent genomic regions. Using paired-end, short-read sequencing data from two groups of individuals expressing divergent phenotypes, we generate a de novo rough-draft genome, identify SNPs and calculate genomewide FST differences between phenotypic groups. As genomes generated by Pool-Seq data are highly fragmented, we also present an approach for super-scaffolding contigs using existing protein-coding data sets. Using this approach, we reanalysed genomic data from two recent studies of birds and butterflies investigating colour pattern variation and replicated their core findings, demonstrating the accuracy and power of a Pool-Seq-only approach. Additionally, we discovered new regions of high divergence and new annotations that together suggest novel parallels between birds and butterflies in the origins of their colour pattern variation.
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Affiliation(s)
| | - Emily A Hornett
- Department of Biology, Pennsylvania State University, University Park, PA, USA.,Department of Zoology, University of Cambridge, Cambridge, UK
| | - Jason A Hill
- Department of Zoology, Stockholm University, Stockholm, Sweden
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21
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Brown AP, Greenway R, Morgan S, Quackenbush CR, Giordani L, Arias-Rodriguez L, Tobler M, Kelley JL. Genome-scale data reveal that endemic Poecilia populations from small sulphidic springs display no evidence of inbreeding. Mol Ecol 2017; 26:4920-4934. [PMID: 28731545 DOI: 10.1111/mec.14249] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 04/04/2017] [Accepted: 06/21/2017] [Indexed: 12/27/2022]
Abstract
Populations with limited ranges can be highly vulnerable to changes in their environment and are, thus, of high conservation concern. Populations that experience human-induced range reductions are often highly inbred and lack genetic diversity, but it is unknown whether this is also the case for populations with naturally small ranges. The fishes Poecilia sulphuraria (listed as critically endangered) and Poecilia thermalis, which are endemic to small hydrogen sulphide-rich springs in southern Mexico, are examples of such populations with inherently small habitats. We used geometric morphometrics and population genetics to quantify phenotypic and genetic variation within and among two populations of P. sulphuraria and one population of P. thermalis. Principal component analyses revealed phenotypic and genetic differences among the populations. Evidence for inbreeding was low compared to populations that have undergone habitat reduction. The genetic data were also used to infer the demographic history of these populations to obtain estimates for effective population sizes and migration rates. Effective population sizes were large given the small habitats of these populations. Our results imply that these three endemic extremophile populations should each be considered separately for conservation purposes. Additionally, this study suggests that populations in naturally small habitats may have lower rates of inbreeding and higher genetic diversity than expected, and therefore may be better equipped to handle environmental perturbations than anticipated. We caution, however, that the inferred lack of inbreeding and the large effective population sizes could potentially be a result of colonization by genetically diverse ancestors.
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Affiliation(s)
- Anthony P Brown
- School of Biological Sciences, Washington State University, Pullman, WA, USA
| | - Ryan Greenway
- Division of Biology, Kansas State University, Manhattan, KS, USA
| | - Samuel Morgan
- Division of Biology, Kansas State University, Manhattan, KS, USA
| | - Corey R Quackenbush
- School of Biological Sciences, Washington State University, Pullman, WA, USA
| | | | - Lenin Arias-Rodriguez
- División Académica de Ciencias Biológicas, Universidad Juárez Autónoma de Tabasco (UJAT), Villahermosa, Tabasco, México
| | - Michael Tobler
- Division of Biology, Kansas State University, Manhattan, KS, USA
| | - Joanna L Kelley
- School of Biological Sciences, Washington State University, Pullman, WA, USA
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22
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Phuong MA, Bi K, Moritz C. Range instability leads to cytonuclear discordance in a morphologically cryptic ground squirrel species complex. Mol Ecol 2017; 26:4743-4755. [PMID: 28734067 DOI: 10.1111/mec.14238] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Accepted: 06/15/2017] [Indexed: 01/06/2023]
Abstract
The processes responsible for cytonuclear discordance frequently remain unclear. Here, we employed an exon capture data set and demographic methods to test hypotheses generated by species distribution models to examine how contrasting histories of range stability vs. fluctuation have caused cytonuclear concordance and discordance in ground squirrel lineages from the Otospermophilus beecheyi species complex. Previous studies in O. beecheyi revealed three morphologically cryptic and highly divergent mitochondrial DNA lineages (named the Northern, Central and Southern lineages based on geography) with only the Northern lineage exhibiting concordant divergence for nuclear genes. Here, we showed that these mtDNA lineages likely formed in allopatry during the Pleistocene, but responded differentially to climatic changes that occurred since the last interglacial (~120,000 years ago). We find that the Northern lineage maintained a stable range throughout this period, correlating with genetic distinctiveness among all genetic markers and low migration rates with the other lineages. In contrast, our results suggested that the Southern lineage expanded from Baja California Sur during the Late Pleistocene to overlap and potentially swamp a contracting Central lineage. High rates of intraspecific gene flow between Southern lineage individuals among expansion origin and expansion edge populations largely eroded Central ancestry from autosomal markers. However, male-biased dispersal in this system preserved signals of this past hybridization and introgression event in matrilineal-biased X-chromosome and mtDNA markers. Our results highlight the importance of range stability in maintaining the persistence of phylogeographic lineages, whereas unstable range dynamics can increase the tendency for lineages to merge upon secondary contact.
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Affiliation(s)
- Mark A Phuong
- Department of Integrative Biology and Museum of Vertebrate Zoology, University of California, Berkeley, CA, USA
| | - Ke Bi
- Department of Integrative Biology and Museum of Vertebrate Zoology, University of California, Berkeley, CA, USA.,Computational Genomics Resource Laboratory, California Institute for Quantitative Biosciences, University of California, Berkeley, CA, USA
| | - Craig Moritz
- Department of Integrative Biology and Museum of Vertebrate Zoology, University of California, Berkeley, CA, USA.,Research School of Biology and Centre for Biodiversity Analysis, The Australian National University, Acton, ACT, Australia
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23
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Wong Miller KM, Bracewell RR, Eisen MB, Bachtrog D. Patterns of Genome-Wide Diversity and Population Structure in the Drosophila athabasca Species Complex. Mol Biol Evol 2017; 34:1912-1923. [PMID: 28431021 PMCID: PMC5850846 DOI: 10.1093/molbev/msx134] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The Drosophila athabasca species complex contains three recently diverged, prezygotically isolated semispecies (Western-Northern, Eastern-A, and Eastern-B) that are distributed across North America and share zones of sympatry. Inferences based on a handful of loci suggest that this complex might be an ideal system for studying the genetics of incipient speciation and the evolution of prezygotic isolating mechanisms, but patterns of differentiation have not been characterized systematically. Here, we assembled a draft genome for D. athabasca and analyze whole-genome re-sequencing data for 28 individuals from across the species range to characterize genome-wide patterns of diversity and population differentiation among semispecies. Patterns of differentiation on the X-chromosome vs. autosomes vary, with the X-chromosome showing better phylogenetic resolution and increased levels of between semispecies divergence. Despite low levels of overall differentiation and a lack of phylogenetic resolution of the autosomes for the most closely related semispecies, individuals do exhibit distinct genetic clustering. Demographic analyses provide some support for a model of isolation with migration within D. athabasca, with divergence times <20 kya. The young divergence times of the semispecies of D. athabasca, together with strong levels of sexual isolation, makes them a promising system for studying the evolution of prezygotic isolation and speciation.
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Affiliation(s)
- Karen M. Wong Miller
- Department of Integrative Biology, University of California Berkeley, Berkeley, CA
| | - Ryan R. Bracewell
- Department of Integrative Biology, University of California Berkeley, Berkeley, CA
| | - Michael B. Eisen
- Department of Integrative Biology, University of California Berkeley, Berkeley, CA
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA
- Howard Hughes Medical Institute, University of California Berkeley, Berkeley, CA
| | - Doris Bachtrog
- Department of Integrative Biology, University of California Berkeley, Berkeley, CA
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24
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Li X, Jian Y, Xie C, Wu J, Xu Y, Zou C. Fast diffusion of domesticated maize to temperate zones. Sci Rep 2017; 7:2077. [PMID: 28522839 PMCID: PMC5437101 DOI: 10.1038/s41598-017-02125-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 04/06/2017] [Indexed: 11/09/2022] Open
Abstract
Adaptation to a temperate climate was a prerequisite for the spread of maize across a broad geographical range. To explicitly explore the demographic process underlying maize adaptation, we used a diffusion-based method to model the differentiation between temperate and tropical populations using the Non-Stiff Stalk group as a proxy for temperate maize. Based on multiple sequential Markovian coalescent approaches, we estimate that tropical and temperate maize diverged approximately 3'000 to 5'000 years ago and the population size shrank after the split. Using composite likelihood approaches, we identified a distinct tropical-temperate divergence event initiated 4'958 years ago (95% confidence interval (CI): 4'877-5'039) from an ancestral population whose effective size was 24,162 (95% CI: 23,914-24,409). We found that continuous gene flow between tropical and temperate maize accompanied the differentiation of temperate maize. Long identical-by-descent tracts shared by tropical and temperate inbred lines have been identified, which might be the result of gene flow between tropical and temperate maize or artificial selection during domestication and crop improvement. Understanding the demographic history of maize diffusion not only provides evidence for population dynamics of maize, but will also assist the identification of regions under selection and the genetic basis of complex traits of agronomic importance.
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Affiliation(s)
- Xiaolong Li
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
- Centre of Pear Engineering Technology Research, State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yinqiao Jian
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Chuanxiao Xie
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Jun Wu
- Centre of Pear Engineering Technology Research, State Key Laboratory of Crop Genetics and Germplasm Enhancement, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yunbi Xu
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
- International Maize and Wheat Improvement Center (CIMMYT), El Batán, 56130, Texcoco, Mexico.
| | - Cheng Zou
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
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Qi X, An H, Ragsdale AP, Hall TE, Gutenkunst RN, Chris Pires J, Barker MS. Genomic inferences of domestication events are corroborated by written records in Brassica rapa. Mol Ecol 2017; 26:3373-3388. [PMID: 28371014 DOI: 10.1111/mec.14131] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Revised: 03/15/2017] [Accepted: 03/17/2017] [Indexed: 12/26/2022]
Abstract
Demographic modelling is often used with population genomic data to infer the relationships and ages among populations. However, relatively few analyses are able to validate these inferences with independent data. Here, we leverage written records that describe distinct Brassica rapa crops to corroborate demographic models of domestication. Brassica rapa crops are renowned for their outstanding morphological diversity, but the relationships and order of domestication remain unclear. We generated genomewide SNPs from 126 accessions collected globally using high-throughput transcriptome data. Analyses of more than 31,000 SNPs across the B. rapa genome revealed evidence for five distinct genetic groups and supported a European-Central Asian origin of B. rapa crops. Our results supported the traditionally recognized South Asian and East Asian B. rapa groups with evidence that pak choi, Chinese cabbage and yellow sarson are likely monophyletic groups. In contrast, the oil-type B. rapa subsp. oleifera and brown sarson were polyphyletic. We also found no evidence to support the contention that rapini is the wild type or the earliest domesticated subspecies of B. rapa. Demographic analyses suggested that B. rapa was introduced to Asia 2,400-4,100 years ago, and that Chinese cabbage originated 1,200-2,100 years ago via admixture of pak choi and European-Central Asian B. rapa. We also inferred significantly different levels of founder effect among the B. rapa subspecies. Written records from antiquity that document these crops are consistent with these inferences. The concordance between our age estimates of domestication events with historical records provides unique support for our demographic inferences.
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Affiliation(s)
- Xinshuai Qi
- Department of Ecology & Evolutionary Biology, University of Arizona, Tucson, AZ, USA
| | - Hong An
- Division of Biological Sciences, University of Missouri, Columbia, MI, USA.,National Key Lab of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, China
| | - Aaron P Ragsdale
- Program in Applied Mathematics, University of Arizona, Tucson, AZ, USA
| | - Tara E Hall
- Department of Ecology & Evolutionary Biology, University of Arizona, Tucson, AZ, USA
| | - Ryan N Gutenkunst
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ, USA
| | - J Chris Pires
- Division of Biological Sciences, University of Missouri, Columbia, MI, USA
| | - Michael S Barker
- Department of Ecology & Evolutionary Biology, University of Arizona, Tucson, AZ, USA
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26
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Nunziata SO, Lance SL, Scott DE, Lemmon EM, Weisrock DW. Genomic data detect corresponding signatures of population size change on an ecological time scale in two salamander species. Mol Ecol 2017; 26:1060-1074. [PMID: 28026889 DOI: 10.1111/mec.13988] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Revised: 11/15/2016] [Accepted: 11/16/2016] [Indexed: 12/25/2022]
Abstract
Understanding the demography of species over recent history (e.g. <100 years) is critical in studies of ecology and evolution, but records of population history are rarely available. Surveying genetic variation is a potential alternative to census-based estimates of population size, and can yield insight into the demography of a population. However, to assess the performance of genetic methods, it is important to compare their estimates of population history to known demography. Here, we leveraged the exceptional resources from a wetland with 37 years of amphibian mark-recapture data to study the utility of genetically based demographic inference on salamander species with documented population declines (Ambystoma talpoideum) and expansions (A. opacum), patterns that have been shown to be correlated with changes in wetland hydroperiod. We generated ddRAD data from two temporally sampled populations of A. opacum (1993, 2013) and A. talpoideum (1984, 2011) and used coalescent-based demographic inference to compare alternate evolutionary models. For both species, demographic model inference supported population size changes that corroborated mark-recapture data. Parameter estimation in A. talpoideum was robust to our variations in analytical approach, while estimates for A. opacum were highly inconsistent, tempering our confidence in detecting a demographic trend in this species. Overall, our robust results in A. talpoideum suggest that genome-based demographic inference has utility on an ecological scale, but researchers should also be cognizant that these methods may not work in all systems and evolutionary scenarios. Demographic inference may be an important tool for population monitoring and conservation management planning.
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Affiliation(s)
- Schyler O Nunziata
- Department of Biology, University of Kentucky, Lexington, KY, 40506, USA
| | - Stacey L Lance
- Savannah River Ecology Laboratory, University of Georgia, P O Drawer E, Aiken, SC, 29802, USA
| | - David E Scott
- Savannah River Ecology Laboratory, University of Georgia, P O Drawer E, Aiken, SC, 29802, USA
| | | | - David W Weisrock
- Department of Biology, University of Kentucky, Lexington, KY, 40506, USA
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27
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Xuereb ATJ, Rouse JD, Cunnington G, Lougheed SC. Population genetic structure at the northern range limit of the threatened eastern hog-nosed snake (Heterodon platirhinos). CONSERV GENET 2015. [DOI: 10.1007/s10592-015-0737-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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28
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Evidence for extensive horizontal gene transfer from the draft genome of a tardigrade. Proc Natl Acad Sci U S A 2015; 112:15976-81. [PMID: 26598659 DOI: 10.1073/pnas.1510461112] [Citation(s) in RCA: 107] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Horizontal gene transfer (HGT), or the transfer of genes between species, has been recognized recently as more pervasive than previously suspected. Here, we report evidence for an unprecedented degree of HGT into an animal genome, based on a draft genome of a tardigrade, Hypsibius dujardini. Tardigrades are microscopic eight-legged animals that are famous for their ability to survive extreme conditions. Genome sequencing, direct confirmation of physical linkage, and phylogenetic analysis revealed that a large fraction of the H. dujardini genome is derived from diverse bacteria as well as plants, fungi, and Archaea. We estimate that approximately one-sixth of tardigrade genes entered by HGT, nearly double the fraction found in the most extreme cases of HGT into animals known to date. Foreign genes have supplemented, expanded, and even replaced some metazoan gene families within the tardigrade genome. Our results demonstrate that an unexpectedly large fraction of an animal genome can be derived from foreign sources. We speculate that animals that can survive extremes may be particularly prone to acquiring foreign genes.
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Hasselmann M, Ferretti L, Zayed A. Beyond fruit-flies: population genomic advances in non-Drosophila arthropods. Brief Funct Genomics 2015; 14:424-31. [DOI: 10.1093/bfgp/elv010] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
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30
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Robinson JD, Coffman AJ, Hickerson MJ, Gutenkunst RN. Sampling strategies for frequency spectrum-based population genomic inference. BMC Evol Biol 2014; 14:254. [PMID: 25471595 PMCID: PMC4269862 DOI: 10.1186/s12862-014-0254-4] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Accepted: 11/24/2014] [Indexed: 01/25/2023] Open
Abstract
Background The allele frequency spectrum (AFS) consists of counts of the number of single nucleotide polymorphism (SNP) loci with derived variants present at each given frequency in a sample. Multiple approaches have recently been developed for parameter estimation and calculation of model likelihoods based on the joint AFS from two or more populations. We conducted a simulation study of one of these approaches, implemented in the Python module δaδi, to compare parameter estimation and model selection accuracy given different sample sizes under one- and two-population models. Results Our simulations included a variety of demographic models and two parameterizations that differed in the timing of events (divergence or size change). Using a number of SNPs reasonably obtained through next-generation sequencing approaches (10,000 - 50,000), accurate parameter estimates and model selection were possible for models with more ancient demographic events, even given relatively small numbers of sampled individuals. However, for recent events, larger numbers of individuals were required to achieve accuracy and precision in parameter estimates similar to that seen for models with older divergence or population size changes. We quantify i) the uncertainty in model selection, using tools from information theory, and ii) the accuracy and precision of parameter estimates, using the root mean squared error, as a function of the timing of demographic events, sample sizes used in the analysis, and complexity of the simulated models. Conclusions Here, we illustrate the utility of the genome-wide AFS for estimating demographic history and provide recommendations to guide sampling in population genomics studies that seek to draw inference from the AFS. Our results indicate that larger samples of individuals (and thus larger AFS) provide greater power for model selection and parameter estimation for more recent demographic events. Electronic supplementary material The online version of this article (doi:10.1186/s12862-014-0254-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- John D Robinson
- Department of Biology, City College of New York, New York, NY, 10031, USA. .,Current Address: South Carolina Department of Natural Resources, Marine Resources Research Institute, Charleston, SC, 29412, USA.
| | - Alec J Coffman
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ, 85721, USA.
| | - Michael J Hickerson
- Department of Biology, City College of New York, New York, NY, 10031, USA. .,Subprogram in Ecology, Evolution and Behavior, the Graduate Center of the City University of New York, New York, NY, 10016, USA. .,Division of Invertebrate Zoology, American Museum of Natural History, New York, NY, 10024, USA.
| | - Ryan N Gutenkunst
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ, 85721, USA.
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Hemmer-Hansen J, Therkildsen NO, Pujolar JM. Population genomics of marine fishes: next-generation prospects and challenges. THE BIOLOGICAL BULLETIN 2014; 227:117-132. [PMID: 25411371 DOI: 10.1086/bblv227n2p117] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Over the past few years, technological advances have facilitated giant leaps forward in our ability to generate genome-wide molecular data, offering exciting opportunities for gaining new insights into the ecology and evolution of species where genomic information is still limited. Marine fishes are valuable organisms for advancing our understanding of evolution on historical and contemporary time scales, and here we highlight areas in which research on these species is likely to be particularly important in the near future. These include possibilities for gaining insights into processes on ecological time scales, identifying genomic signatures associated with population divergence under gene flow, and determining the genetic basis of phenotypic traits. We also consider future challenges pertaining to the implementation of genome-wide coverage through next-generation sequencing and genotyping methods in marine fishes. Complications associated with fast decay of linkage disequilibrium, as expected for species with large effective population sizes, and the possibility that adaptation is associated with both soft selective sweeps and polygenic selection, leaving complex genomic signatures in natural populations, are likely to challenge future studies. However, the combination of high genome coverage and new statistical developments offers promising solutions. Thus, the next generation of studies is likely to truly facilitate the transition from population genetics to population genomics in marine fishes. This transition will advance our understanding of basic evolutionary processes and will offer new possibilities for conservation and management of valuable marine resources.
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Affiliation(s)
- Jakob Hemmer-Hansen
- Section for Marine Living Resources, National Institute of Aquatic Resources, Technical University of Denmark, Vejlsøvej 39, DK-8600 Silkeborg, Denmark;
| | | | - José Martin Pujolar
- Department of Bioscience, Aarhus University, Ny Munkegade 114, DK-8000 Aarhus C, Denmark
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Harris SE, O'Neill RJ, Munshi-South J. Transcriptome resources for the white-footed mouse (Peromyscus leucopus): new genomic tools for investigating ecologically divergent urban and rural populations. Mol Ecol Resour 2014; 15:382-94. [PMID: 24980186 DOI: 10.1111/1755-0998.12301] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 06/26/2014] [Accepted: 06/27/2014] [Indexed: 12/30/2022]
Abstract
Genomic resources are important and attainable for examining evolutionary change in divergent natural populations of nonmodel species. We utilized two next-generation sequencing (NGS) platforms, 454 and SOLiD 5500XL, to assemble low-coverage transcriptomes of the white-footed mouse (Peromyscus leucopus), a widespread and abundant native rodent in eastern North America. We sequenced liver mRNA transcripts from multiple individuals collected from urban populations in New York City and rural populations in undisturbed protected areas nearby and assembled a reference transcriptome using 1 080 065 954 SOLiD 5500XL (75 bp) reads and 3 052 640 454 GS FLX + reads. The reference contained 40 908 contigs with a N50 = 1044 bp and a total content of 30.06 Megabases (Mb). Contigs were annotated from Mus musculus (39.96% annotated) Uniprot databases. We identified 104 655 high-quality single nucleotide polymorphisms (SNPs) and 65 single sequence repeats (SSRs) with flanking primers. We also used normalized read counts to identify putative gene expression differences in 10 genes between populations. There were 19 contigs significantly differentially expressed in urban populations compared to rural populations, with gene function annotations generally related to the translation and modification of proteins and those involved in immune responses. The individual transcriptomes generated in this study will be used to investigate evolutionary responses to urbanization. The reference transcriptome provides a valuable resource for the scientific community using North American Peromyscus species as emerging model systems for ecological genetics and adaptation.
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Affiliation(s)
- Stephen E Harris
- Program in Ecology, Evolutionary Biology, & Behavior, The Graduate Center, City University of New York (CUNY), New York, NY, 10016, USA
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