151
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Hooper R, Brealey JC, van der Valk T, Alberdi A, Durban JW, Fearnbach H, Robertson KM, Baird RW, Bradley Hanson M, Wade P, Gilbert MTP, Morin PA, Wolf JBW, Foote AD, Guschanski K. Host-derived population genomics data provides insights into bacterial and diatom composition of the killer whale skin. Mol Ecol 2019; 28:484-502. [PMID: 30187987 PMCID: PMC6487819 DOI: 10.1111/mec.14860] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 08/15/2018] [Accepted: 08/27/2018] [Indexed: 12/20/2022]
Abstract
Recent exploration into the interactions and relationship between hosts and their microbiota has revealed a connection between many aspects of the host's biology, health and associated micro-organisms. Whereas amplicon sequencing has traditionally been used to characterize the microbiome, the increasing number of published population genomics data sets offers an underexploited opportunity to study microbial profiles from the host shotgun sequencing data. Here, we use sequence data originally generated from killer whale Orcinus orca skin biopsies for population genomics, to characterize the skin microbiome and investigate how host social and geographical factors influence the microbial community composition. Having identified 845 microbial taxa from 2.4 million reads that did not map to the killer whale reference genome, we found that both ecotypic and geographical factors influence community composition of killer whale skin microbiomes. Furthermore, we uncovered key taxa that drive the microbiome community composition and showed that they are embedded in unique networks, one of which is tentatively linked to diatom presence and poor skin condition. Community composition differed between Antarctic killer whales with and without diatom coverage, suggesting that the previously reported episodic migrations of Antarctic killer whales to warmer waters associated with skin turnover may control the effects of potentially pathogenic bacteria such as Tenacibaculum dicentrarchi. Our work demonstrates the feasibility of microbiome studies from host shotgun sequencing data and highlights the importance of metagenomics in understanding the relationship between host and microbial ecology.
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Affiliation(s)
- Rebecca Hooper
- Animal EcologyDepartment of Ecology and GeneticsEvolutionary Biology CentreUppsala UniversityUppsalaSweden
| | - Jaelle C. Brealey
- Animal EcologyDepartment of Ecology and GeneticsEvolutionary Biology CentreUppsala UniversityUppsalaSweden
| | - Tom van der Valk
- Animal EcologyDepartment of Ecology and GeneticsEvolutionary Biology CentreUppsala UniversityUppsalaSweden
| | - Antton Alberdi
- Centre for GeoGeneticsNatural History Museum of DenmarkUniversity of CopenhagenCopenhagen KDenmark
| | - John W. Durban
- Marine Mammal and Turtle DivisionSouthwest Fisheries Science CenterNational Marine Fisheries ServiceNational Oceanic and Atmospheric AdministrationLa JollaCalifornia
| | - Holly Fearnbach
- SR3, SeaLife Response, Rehabilitation, and ResearchSeattleWashington
| | - Kelly M. Robertson
- Marine Mammal and Turtle DivisionSouthwest Fisheries Science CenterNational Marine Fisheries ServiceNational Oceanic and Atmospheric AdministrationLa JollaCalifornia
| | | | - M. Bradley Hanson
- Northwest Fisheries Science CenterNational Marine Fisheries ServiceNational Oceanic and Atmospheric AdministrationSeattleWashington
| | - Paul Wade
- National Marine Mammal LaboratoryAlaska Fisheries Science CenterNational Marine Fisheries ServiceNational Oceanic and Atmospheric AdministrationSeattleWashington
| | - M. Thomas P. Gilbert
- Centre for GeoGeneticsNatural History Museum of DenmarkUniversity of CopenhagenCopenhagen KDenmark
- NTNU University MuseumTrondheimNorway
| | - Phillip A. Morin
- Marine Mammal and Turtle DivisionSouthwest Fisheries Science CenterNational Marine Fisheries ServiceNational Oceanic and Atmospheric AdministrationLa JollaCalifornia
| | - Jochen B. W. Wolf
- Science of Life Laboratories and Department of Evolutionary BiologyEvolutionary Biology CentreUppsala UniversityUppsalaSweden
- Section of Evolutionary BiologyFaculty of BiologyLMU MunichMunichGermany
| | - Andrew D. Foote
- Molecular Ecology and Fisheries Genetics LaboratorySchool of Biological SciencesBangor UniversityBangorGwyneddUK
| | - Katerina Guschanski
- Animal EcologyDepartment of Ecology and GeneticsEvolutionary Biology CentreUppsala UniversityUppsalaSweden
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152
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Friis G, Fandos G, Zellmer AJ, McCormack JE, Faircloth BC, Milá B. Genome-wide signals of drift and local adaptation during rapid lineage divergence in a songbird. Mol Ecol 2018; 27:5137-5153. [PMID: 30451354 DOI: 10.1111/mec.14946] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 09/26/2018] [Accepted: 10/15/2018] [Indexed: 12/25/2022]
Abstract
The formation of independent evolutionary lineages involves neutral and selective factors, and understanding their relative roles in population divergence is a fundamental goal of speciation research. Correlations between allele frequencies and environmental variability can reveal the role of selection, yet the relative contribution of drift can be difficult to establish. Recently diversified taxa like the Oregon junco (Aves, Passerellidae, Junco hyemalis oreganus) of western North America provide ideal scenarios to apply genetic-environment association analyses (GEA) while controlling for population structure. Analysis of genome-wide SNP loci revealed marked genetic structure consisting of differentiated populations in isolated, dry southern mountain ranges, and less divergent, recently expanded populations in humid northern latitudes. We used correlations between genomic and environmental variance to test for three specific modes of evolutionary divergence: (a) drift in geographic isolation, (b) differentiation along continuous selective gradients and (c) isolation-by-adaptation. We found evidence of strong drift in southern mountains, but also signals of local adaptation driven by temperature, precipitation, elevation and vegetation, especially when controlling for population history. We identified numerous variants under selection scattered across the genome, suggesting that local adaptation can promote rapid differentiation when acting over multiple independent loci.
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Affiliation(s)
- Guillermo Friis
- National Museum of Natural Sciences, Spanish National Research Council (CSIC), Madrid, Spain
| | - Guillermo Fandos
- Department of Biodiversity, Ecology and Evolution, Complutense University of Madrid, Madrid, Spain
| | - Amanda J Zellmer
- Department of Biology, Occidental College, Los Angeles, California
| | - John E McCormack
- Department of Biology, Occidental College, Los Angeles, California.,Moore Laboratory of Zoology and Department of Biology, Occidental College, Los Angeles, California
| | - Brant C Faircloth
- Department of Biological Sciences and Museum of Natural Science, Louisiana State University, Baton Rouge, Louisiana
| | - Borja Milá
- National Museum of Natural Sciences, Spanish National Research Council (CSIC), Madrid, Spain
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153
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Wang Q, Lu W, Yang J, Jiang L, Zhang Q, Kan X, Yang X. Comparative transcriptomics in three Passerida species provides insights into the evolution of avian mitochondrial complex I. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY D-GENOMICS & PROTEOMICS 2018; 28:27-36. [DOI: 10.1016/j.cbd.2018.06.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 06/04/2018] [Accepted: 06/13/2018] [Indexed: 02/02/2023]
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154
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Uy JAC, Irwin DE, Webster MS. Behavioral Isolation and Incipient Speciation in Birds. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2018. [DOI: 10.1146/annurev-ecolsys-110617-062646] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Behavioral changes, such as those involved in mating, foraging, and migration, can generate reproductive barriers between populations. Birds, in particular, are known for their great diversity in these behaviors, and so behavioral isolation is often proposed to be the major driver of speciation. Here, we review empirical evidence to evaluate the importance of behavioral isolation in the early stages of avian speciation. Experimentally measured mating preferences indicate that changes in mating behavior can result in premating barriers, with their strength depending on the extent of divergence in mating signals. Differences in migratory and foraging behavior also can play important roles in generating reproductive barriers in the early stages of speciation. However, because premating behavioral isolation is imperfect, extrinsic postzygotic barriers, in the form of selection against hybrids having intermediate phenotypes, also play an important role in avian diversification, especially in completing the speciation process.
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Affiliation(s)
- J. Albert C. Uy
- Department of Biology, University of Miami, Coral Gables, Florida 33146, USA
| | - Darren E. Irwin
- Department of Zoology, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Michael S. Webster
- Cornell Lab of Ornithology and Department of Neurobiology and Behavior, Cornell University, Ithaca, New York 14850, USA
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155
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Kardos M, Shafer AB. The Peril of Gene-Targeted Conservation. Trends Ecol Evol 2018; 33:827-839. [DOI: 10.1016/j.tree.2018.08.011] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Revised: 08/27/2018] [Accepted: 08/28/2018] [Indexed: 01/01/2023]
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156
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Abolins-Abols M, Kornobis E, Ribeca P, Wakamatsu K, Peterson MP, Ketterson ED, Milá B. Differential gene regulation underlies variation in melanic plumage coloration in the dark-eyed junco (Junco hyemalis
). Mol Ecol 2018; 27:4501-4515. [DOI: 10.1111/mec.14878] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2018] [Revised: 08/22/2018] [Accepted: 09/07/2018] [Indexed: 01/01/2023]
Affiliation(s)
- Mikus Abolins-Abols
- Department of Animal Biology; University of Illinois; Urbana Illinois
- Department of Biology; Indiana University; Bloomington Indiana
| | - Etienne Kornobis
- National Museum of Natural Sciences; Spanish National Research Council (CSIC); Madrid Spain
| | | | - Kazumasa Wakamatsu
- Department of Chemistry; Fujita Health University School of Health Sciences; Toyoake Aichi Japan
| | | | | | - Borja Milá
- National Museum of Natural Sciences; Spanish National Research Council (CSIC); Madrid Spain
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157
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Tilak MK, Botero-Castro F, Galtier N, Nabholz B. Illumina Library Preparation for Sequencing the GC-Rich Fraction of Heterogeneous Genomic DNA. Genome Biol Evol 2018; 10:616-622. [PMID: 29385572 PMCID: PMC5808798 DOI: 10.1093/gbe/evy022] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/18/2018] [Indexed: 02/06/2023] Open
Abstract
Standard Illumina libraries are biased toward sequences of intermediate GC-content. This results in an underrepresentation of GC-rich regions in sequencing projects of genomes with heterogeneous base composition, such as mammals and birds. We developed a simple, cost-effective protocol to enrich sheared genomic DNA in its GC-rich fraction by subtracting AT-rich DNA. This was achieved by heating DNA up to 90 °C before applying Illumina library preparation. We tested the new approach on chicken DNA and found that heated DNA increased average coverage in the GC-richest chromosomes by a factor up to six. Using a Taq polymerase supposedly appropriate for PCR amplification of GC-rich sequences had a much weaker effect. Our protocol should greatly facilitate sequencing and resequencing of the GC-richest regions of heterogeneous genomes, in combination with standard short-read and long-read technologies.
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Affiliation(s)
- Marie-Ka Tilak
- Institut des Sciences de l'Evolution, ISEM, Université de Montellier, CNRS, IRD, EPHE, France
| | - Fidel Botero-Castro
- Institut des Sciences de l'Evolution, ISEM, Université de Montellier, CNRS, IRD, EPHE, France
| | - Nicolas Galtier
- Institut des Sciences de l'Evolution, ISEM, Université de Montellier, CNRS, IRD, EPHE, France
| | - Benoit Nabholz
- Institut des Sciences de l'Evolution, ISEM, Université de Montellier, CNRS, IRD, EPHE, France
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158
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Abstract
Populations often show “islands of divergence” in the genome. Analysis of divergence between subspecies of Antirrhinum that differ in flower color patterns shows that sharp peaks in relative divergence occur at two causal loci. The island is shaped by a combination of gene flow and multiple selective sweeps, showing how divergence and barriers between populations can arise and be maintained. Genomes of closely-related species or populations often display localized regions of enhanced relative sequence divergence, termed genomic islands. It has been proposed that these islands arise through selective sweeps and/or barriers to gene flow. Here, we genetically dissect a genomic island that controls flower color pattern differences between two subspecies of Antirrhinum majus, A.m.striatum and A.m.pseudomajus, and relate it to clinal variation across a natural hybrid zone. We show that selective sweeps likely raised relative divergence at two tightly-linked MYB-like transcription factors, leading to distinct flower patterns in the two subspecies. The two patterns provide alternate floral guides and create a strong barrier to gene flow where populations come into contact. This barrier affects the selected flower color genes and tightly-linked loci, but does not extend outside of this domain, allowing gene flow to lower relative divergence for the rest of the chromosome. Thus, both selective sweeps and barriers to gene flow play a role in shaping genomic islands: sweeps cause elevation in relative divergence, while heterogeneous gene flow flattens the surrounding “sea,” making the island of divergence stand out. By showing how selective sweeps establish alternative adaptive phenotypes that lead to barriers to gene flow, our study sheds light on possible mechanisms leading to reproductive isolation and speciation.
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159
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Damas J, Kim J, Farré M, Griffin DK, Larkin DM. Reconstruction of avian ancestral karyotypes reveals differences in the evolutionary history of macro- and microchromosomes. Genome Biol 2018; 19:155. [PMID: 30290830 PMCID: PMC6173868 DOI: 10.1186/s13059-018-1544-8] [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] [Received: 01/12/2018] [Accepted: 09/18/2018] [Indexed: 11/29/2022] Open
Abstract
Background Reconstruction of ancestral karyotypes is critical for our understanding of genome evolution, allowing for the identification of the gross changes that shaped extant genomes. The identification of such changes and their time of occurrence can shed light on the biology of each species, clade and their evolutionary history. However, this is impeded by both the fragmented nature of the majority of genome assemblies and the limitations of the available software to work with them. These limitations are particularly apparent in birds, with only 10 chromosome-level assemblies reported thus far. Algorithmic approaches applied to fragmented genome assemblies can nonetheless help define patterns of chromosomal change in defined taxonomic groups. Results Here, we make use of the DESCHRAMBLER algorithm to perform the first large-scale study of ancestral chromosome structure and evolution in birds. This algorithm allows us to reconstruct the overall genome structure of 14 key nodes of avian evolution from the Avian ancestor to the ancestor of the Estrildidae, Thraupidae and Fringillidae families. Conclusions Analysis of these reconstructions provides important insights into the variability of rearrangement rates during avian evolution and allows the detection of patterns related to the chromosome distribution of evolutionary breakpoint regions. Moreover, the inclusion of microchromosomes in our reconstructions allows us to provide novel insights into the evolution of these avian chromosomes, specifically. Electronic supplementary material The online version of this article (10.1186/s13059-018-1544-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Joana Damas
- Department of Comparative Biomedical Sciences, Royal Veterinary College, University of London, London, NW1 0TU, UK
| | - Jaebum Kim
- Department of Biomedical Science and Engineering, Konkuk University, Seoul, 05029, South Korea
| | - Marta Farré
- Department of Comparative Biomedical Sciences, Royal Veterinary College, University of London, London, NW1 0TU, UK
| | - Darren K Griffin
- School of Biosciences, University of Kent, Canterbury, CT2 7NY, UK
| | - Denis M Larkin
- Department of Comparative Biomedical Sciences, Royal Veterinary College, University of London, London, NW1 0TU, UK.
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160
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Toomey MB, Marques CI, Andrade P, Araújo PM, Sabatino S, Gazda MA, Afonso S, Lopes RJ, Corbo JC, Carneiro M. A non-coding region near Follistatin controls head colour polymorphism in the Gouldian finch. Proc Biol Sci 2018; 285:20181788. [PMID: 30282656 PMCID: PMC6191701 DOI: 10.1098/rspb.2018.1788] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Accepted: 09/05/2018] [Indexed: 12/17/2022] Open
Abstract
Discrete colour morphs coexisting within a single population are common in nature. In a broad range of organisms, sympatric colour morphs often display major differences in other traits, including morphology, physiology or behaviour. Despite the repeated occurrence of this phenomenon, our understanding of the genetics that underlie multi-trait differences and the factors that promote the long-term maintenance of phenotypic variability within a freely interbreeding population are incomplete. Here, we investigated the genetic basis of red and black head colour in the Gouldian finch (Erythrura gouldiae), a classic polymorphic system in which naturally occurring colour morphs also display differences in aggressivity and reproductive success. We show that the candidate locus is a small (approx. 70 kb) non-coding region mapping to the Z chromosome near the Follistatin (FST) gene. Unlike recent findings in other systems where phenotypic morphs are explained by large inversions containing hundreds of genes (so-called supergenes), we did not identify any structural rearrangements between the two haplotypes using linked-read sequencing technology. Nucleotide divergence between the red and black alleles was high when compared to the remainder of the Z chromosome, consistent with their maintenance as balanced polymorphisms over several million years. Our results illustrate how pleiotropic phenotypes can arise from simple genetic variation, probably regulatory in nature.
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Affiliation(s)
- Matthew B Toomey
- Department of Pathology and Immunology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Cristiana I Marques
- CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, 4485-661 Vairão, Portugal
- Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, 4169-007 Porto, Portugal
| | - Pedro Andrade
- CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, 4485-661 Vairão, Portugal
- Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, 4169-007 Porto, Portugal
| | - Pedro M Araújo
- CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, 4485-661 Vairão, Portugal
- Centro de Ciências do Mar e do Ambiente, Departamento de Ciências da Vida, Universidade de Coimbra, 3004-517 Coimbra, Portugal
| | - Stephen Sabatino
- CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, 4485-661 Vairão, Portugal
| | - Małgorzata A Gazda
- CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, 4485-661 Vairão, Portugal
- Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, 4169-007 Porto, Portugal
| | - Sandra Afonso
- CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, 4485-661 Vairão, Portugal
| | - Ricardo J Lopes
- CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, 4485-661 Vairão, Portugal
| | - Joseph C Corbo
- Department of Pathology and Immunology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Miguel Carneiro
- CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, 4485-661 Vairão, Portugal
- Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, 4169-007 Porto, Portugal
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161
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Richards EJ, Poelstra JW, Martin CH. Don't throw out the sympatric speciation with the crater lake water: fine-scale investigation of introgression provides equivocal support for causal role of secondary gene flow in one of the clearest examples of sympatric speciation. Evol Lett 2018; 2:524-540. [PMID: 30283699 PMCID: PMC6145409 DOI: 10.1002/evl3.78] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Revised: 07/13/2018] [Accepted: 07/18/2018] [Indexed: 12/19/2022] Open
Abstract
Genomic data has revealed complex histories of colonization and repeated gene flow previously unrecognized in some of the most celebrated examples of sympatric speciation and radiation. However, much of the evidence for secondary gene flow into these radiations comes from summary statistics calculated from sparse genomic sampling without knowledge of which specific genomic regions introgressed. This tells us little about how gene flow potentially influenced sympatric diversification. Here, we investigated whole genomes of Barombi Mbo crater lake cichlids for fine-scale patterns of introgression with neighboring riverine cichlid populations. We found evidence of secondary gene flow into the radiation scattered across <0.24% of the genome; however, from our analyses, it is not clear if the functional diversity in these regions contributed to the ecological, sexual, and morphological diversity found in the lake. Unlike similar studies, we found no obvious candidate genes for adaptive introgression and we cannot rule out that secondary gene flow was predominantly neutral with respect to the diversification process. We also found evidence for differential assortment of ancestral polymorphisms found in riverine populations between sympatric sister species, suggesting the presence of an ancestral hybrid swarm. Although the history of gene flow and colonization is more complicated than previously assumed, the lack of compelling evidence for secondary gene flow's role in species diversification suggests that we should not yet rule out one of the most celebrated examples of sympatric speciation in nature without a more thorough investigation of the timing and functional role of each introgressed region.
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Affiliation(s)
- Emilie J. Richards
- Biology DepartmentUniversity of North Carolina at Chapel HillChapel HillNorth Carolina27599
| | - Jelmer W. Poelstra
- Biology DepartmentUniversity of North Carolina at Chapel HillChapel HillNorth Carolina27599
- Biology DepartmentDuke UniversityDurhamNorth Carolina27710
| | - Christopher H. Martin
- Biology DepartmentUniversity of North Carolina at Chapel HillChapel HillNorth Carolina27599
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162
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Gao G, Xu M, Bai C, Yang Y, Li G, Xu J, Wei Z, Min J, Su G, Zhou X, Guo J, Hao Y, Zhang G, Yang X, Xu X, Widelitz RB, Chuong CM, Zhang C, Yin J, Zuo Y. Comparative genomics and transcriptomics of Chrysolophus provide insights into the evolution of complex plumage coloration. Gigascience 2018; 7:5091803. [PMID: 30192940 PMCID: PMC6204425 DOI: 10.1093/gigascience/giy113] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Accepted: 08/29/2018] [Indexed: 01/05/2023] Open
Abstract
Background As one of the most recognizable characteristics in birds, plumage color has a high impact on understanding the evolution and mechanisms of coloration. Feather and skin are ideal tissues to explore the genomics and complexity of color patterns in vertebrates. Two species of the genus Chrysolophus, golden pheasant (Chrysolophus pictus) and Lady Amherst's pheasant (Chrysolophus amherstiae), exhibit brilliant colors in their plumage, but with extreme phenotypic differences, making these two species great models to investigate plumage coloration mechanisms in birds. Results We sequenced and assembled a genome of golden pheasant with high coverage and annotated 15,552 protein-coding genes. The genome of Lady Amherst's pheasant is sequenced with low coverage. Based on the feather pigment identification, a series of genomic and transcriptomic comparisons were conducted to investigate the complex features of plumage coloration. By identifying the lineage-specific sequence variations in Chrysolophus and golden pheasant against different backgrounds, we found that four melanogenesis biosynthesis genes and some lipid-related genes might be candidate genomic factors for the evolution of melanin and carotenoid pigmentation, respectively. In addition, a study among 47 birds showed some candidate genes related to carotenoid coloration in a broad range of birds. The transcriptome data further reveal important regulators of the two colorations, particularly one splicing transcript of the microphthalmia-associated transcription factor gene for pheomelanin synthesis. Conclusions Analysis of the golden pheasant and its sister pheasant genomes, as well as comparison with other avian genomes, are helpful to reveal the underlying regulation of their plumage coloration. The present study provides important genomic information and insights for further studies of avian plumage evolution and diversity.
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Affiliation(s)
- Guangqi Gao
- The State key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, Inner Mongolia University, No.235, University West Road, Saihan District,Hohhot, Inner Mongolia, 010021, China.,College of Life Science, Inner Mongolia University, Hohhot, 010070, China
| | - Meng Xu
- BGI Genomics, Co., Ltd. Buiding No.7, BGI Park, No.21 Hongan 3rd Street, Yantian District, Shenzhen, 518083, China
| | - Chunling Bai
- The State key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, Inner Mongolia University, No.235, University West Road, Saihan District,Hohhot, Inner Mongolia, 010021, China.,College of Life Science, Inner Mongolia University, Hohhot, 010070, China
| | - Yulan Yang
- BGI Genomics, Co., Ltd. Buiding No.7, BGI Park, No.21 Hongan 3rd Street, Yantian District, Shenzhen, 518083, China
| | - Guangpeng Li
- The State key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, Inner Mongolia University, No.235, University West Road, Saihan District,Hohhot, Inner Mongolia, 010021, China
| | - Junyang Xu
- BGI Genomics, Co., Ltd. Buiding No.7, BGI Park, No.21 Hongan 3rd Street, Yantian District, Shenzhen, 518083, China
| | - Zhuying Wei
- The State key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, Inner Mongolia University, No.235, University West Road, Saihan District,Hohhot, Inner Mongolia, 010021, China.,College of Life Science, Inner Mongolia University, Hohhot, 010070, China
| | - Jiumeng Min
- BGI Genomics, Co., Ltd. Buiding No.7, BGI Park, No.21 Hongan 3rd Street, Yantian District, Shenzhen, 518083, China
| | - Guanghua Su
- The State key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, Inner Mongolia University, No.235, University West Road, Saihan District,Hohhot, Inner Mongolia, 010021, China.,College of Life Science, Inner Mongolia University, Hohhot, 010070, China
| | - Xianqiang Zhou
- BGI Genomics, Co., Ltd. Buiding No.7, BGI Park, No.21 Hongan 3rd Street, Yantian District, Shenzhen, 518083, China
| | - Jun Guo
- College of Life Science, Inner Mongolia Agricultural University, No.306, Zhaowuda Road, Saihan District, Hohhot, Inner Mongolia, 010018
| | - Yu Hao
- College of Life Science, Inner Mongolia Agricultural University, No.306, Zhaowuda Road, Saihan District, Hohhot, Inner Mongolia, 010018
| | - Guiping Zhang
- BGI Genomics, Co., Ltd. Buiding No.7, BGI Park, No.21 Hongan 3rd Street, Yantian District, Shenzhen, 518083, China
| | - Xukui Yang
- BGI Genomics, Co., Ltd. Buiding No.7, BGI Park, No.21 Hongan 3rd Street, Yantian District, Shenzhen, 518083, China
| | - Xiaomin Xu
- BGI Genomics, Co., Ltd. Buiding No.7, BGI Park, No.21 Hongan 3rd Street, Yantian District, Shenzhen, 518083, China
| | - Randall B Widelitz
- Department of Pathology, Keck School of Medicine, Universit of Southern California, 2011 Zonal Avenue, HMR315B, Los Angeles, CA90033, USA
| | - Cheng-Ming Chuong
- Department of Pathology, Keck School of Medicine, Universit of Southern California, 2011 Zonal Avenue, HMR315B, Los Angeles, CA90033, USA
| | - Chi Zhang
- BGI Genomics, Co., Ltd. Buiding No.7, BGI Park, No.21 Hongan 3rd Street, Yantian District, Shenzhen, 518083, China
| | - Jun Yin
- College of Life Science, Inner Mongolia Agricultural University, No.306, Zhaowuda Road, Saihan District, Hohhot, Inner Mongolia, 010018
| | - Yongchun Zuo
- The State key Laboratory of Reproductive Regulation and Breeding of Grassland Livestock, Inner Mongolia University, No.235, University West Road, Saihan District,Hohhot, Inner Mongolia, 010021, China.,College of Life Science, Inner Mongolia University, Hohhot, 010070, China
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163
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Ng CS, Li WH. Genetic and Molecular Basis of Feather Diversity in Birds. Genome Biol Evol 2018; 10:2572-2586. [PMID: 30169786 PMCID: PMC6171735 DOI: 10.1093/gbe/evy180] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/13/2018] [Indexed: 12/16/2022] Open
Abstract
Feather diversity is striking in many aspects. Although the development of feather has been studied for decades, genetic and genomic studies of feather diversity have begun only recently. Many questions remain to be answered by multidisciplinary approaches. In this review, we discuss three levels of feather diversity: Feather morphotypes, intraspecific variations, and interspecific variations. We summarize recent studies of feather evolution in terms of genetics, genomics, and developmental biology and provide perspectives for future research. Specifically, this review includes the following topics: 1) Diversity of feather morphotype; 2) feather diversity among different breeds of domesticated birds, including variations in pigmentation pattern, in feather length or regional identity, in feather orientation, in feather distribution, and in feather structure; and 3) diversity of feathers among avian species, including plumage color and morph differences between species and the regulatory differences in downy feather development between altricial and precocial birds. Finally, we discussed future research directions.
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Affiliation(s)
- Chen Siang Ng
- Institute of Molecular and Cellular Biology & Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan.,The iEGG and Animal Biotechnology Center, National Chung Hsing University, Taichung, Taiwan
| | - Wen-Hsiung Li
- The iEGG and Animal Biotechnology Center, National Chung Hsing University, Taichung, Taiwan.,Biodiversity Research Center, Academia Sinica, Taipei, Taiwan.,Department of Ecology and Evolution, University of Chicago
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164
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Semenov GA, Basheva EA, Borodin PM, Torgasheva AA. High rate of meiotic recombination and its implications for intricate speciation patterns in the white wagtail (Motacilla alba). Biol J Linn Soc Lond 2018. [DOI: 10.1093/biolinnean/bly133] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Georgy A Semenov
- Ecology and Evolutionary Biology, University of Colorado, Ramaley Hall, Boulder, CO, USA
- Institute of Systematics and Ecology of Animals, Frunze, Novosibirsk, Russian Federation
- Ecology and Evolutionary Biology, University of Colorado, Ramaley Hall, Boulder, CO, USA
| | - Ekaterina A Basheva
- Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, Lavrentiev Ave., Novosibirsk, Russian Federation
| | - Pavel M Borodin
- Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, Lavrentiev Ave., Novosibirsk, Russian Federation
- Novosibirsk State Research University, Department of Cytology and Genetics, Pirogova st., Novosibirsk, Russian Federation
| | - Anna A Torgasheva
- Institute of Systematics and Ecology of Animals, Frunze, Novosibirsk, Russian Federation
- Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, Lavrentiev Ave., Novosibirsk, Russian Federation
- Novosibirsk State Research University, Department of Cytology and Genetics, Pirogova st., Novosibirsk, Russian Federation
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165
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Raposo do Amaral F, Maldonado‐Coelho M, Aleixo A, Luna LW, Rêgo PSD, Araripe J, Souza TO, Silva WAG, Thom G. Recent chapters of Neotropical history overlooked in phylogeography: Shallow divergence explains phenotype and genotype uncoupling in
Antilophia
manakins. Mol Ecol 2018; 27:4108-4120. [DOI: 10.1111/mec.14843] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 06/06/2018] [Accepted: 06/11/2018] [Indexed: 12/15/2022]
Affiliation(s)
- Fabio Raposo do Amaral
- Departamento de Ecologia e Biologia Evolutiva Universidade Federal de São Paulo Diadema SP Brazil
| | - Marcos Maldonado‐Coelho
- Departamento de Ecologia e Biologia Evolutiva Universidade Federal de São Paulo Diadema SP Brazil
| | - Alexandre Aleixo
- Coordenação de Zoologia Museu Paraense Emílio Goeldi Belém PA Brazil
| | - Leilton W. Luna
- Laboratório de Genética e Conservação Instituto de Estudos Costeiros Universidade Federal do Pará Bragança PA Brazil
| | - Péricles Sena do Rêgo
- Laboratório de Genética e Conservação Instituto de Estudos Costeiros Universidade Federal do Pará Bragança PA Brazil
| | - Juliana Araripe
- Laboratório de Genética e Conservação Instituto de Estudos Costeiros Universidade Federal do Pará Bragança PA Brazil
| | - Thainara O. Souza
- Laboratório de Genética e Conservação Instituto de Estudos Costeiros Universidade Federal do Pará Bragança PA Brazil
| | - Weber A. G. Silva
- Associação de Pesquisa e Preservação de Ecossistemas Aquáticos Fortaleza Brazil
| | - Gregory Thom
- Departamento de Genética e Biologia Evolutiva Universidade de São Paulo São Paulo SP Brazil
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166
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Walsh J, Kovach AI, Olsen BJ, Shriver WG, Lovette IJ. Bidirectional adaptive introgression between two ecologically divergent sparrow species. Evolution 2018; 72:2076-2089. [PMID: 30101975 DOI: 10.1111/evo.13581] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 07/10/2018] [Accepted: 07/31/2018] [Indexed: 12/24/2022]
Abstract
Natural hybrid zones can be used to dissect the mechanisms driving key evolutionary processes by allowing us to identify genomic regions important for establishing reproductive isolation and that allow for transfer of adaptive variation. We leverage whole-genome data in a system where two bird species, the saltmarsh (Ammospiza caudacuta) and Nelson's (A. nelsoni) sparrow, hybridize despite their relatively high background genetic differentiation and past ecological divergence. Adaptive introgression is plausible in this system because Nelson's sparrows are recent colonists of saltwater marshes, compared to the specialized saltmarsh sparrow that has a longer history of saltmarsh adaptation. Comparisons among whole-genome sequences of 34 individuals from allopatric and sympatric populations show that ongoing gene flow is shaping the genomic landscape, with allopatric populations exhibiting genome-wide FST estimates close to double of that observed in sympatry. We characterized patterns of introgression across the genome and identify regions that exhibit biased introgression into hybrids from one parental species. These regions offer compelling candidates for genes related to tidal marsh adaptations suggesting that adaptive introgression may be an important consequence of hybridization. These findings highlight the value of considering the landscapes of both genome-wide introgression and divergence when characterizing the evolutionary forces that drive speciation.
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Affiliation(s)
- Jennifer Walsh
- Fuller Evolutionary Biology Program, Cornell Laboratory of Ornithology, Ithaca, New York 14850.,Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, New York 14853
| | - Adrienne I Kovach
- Department of Natural Resources and the Environment, University of New Hampshire, Durham, New Hampshire 03824
| | - Brian J Olsen
- School of Biology and Ecology, University of Maine, Orono, Maine 04469
| | - W Gregory Shriver
- Department of Entomology and Wildlife Ecology, University of Delaware, Newark, Delaware 19716
| | - Irby J Lovette
- Fuller Evolutionary Biology Program, Cornell Laboratory of Ornithology, Ithaca, New York 14850.,Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, New York 14853
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167
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Parchman TL, Edelaar P, Uckele K, Mezquida ET, Alonso D, Jahner JP, Summers RW, Benkman CW. Resource stability and geographic isolation are associated with genome divergence in western Palearctic crossbills. J Evol Biol 2018; 31:1715-1731. [PMID: 30125437 DOI: 10.1111/jeb.13367] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 07/25/2018] [Accepted: 08/11/2018] [Indexed: 01/08/2023]
Abstract
While many conifers produce annually variable seed crops, serotinous species (which hold seeds in cones for multiple years) represent unusually stable food resources for seed predators. Such stability is conducive to residency and potentially population divergence of consumers as exemplified by the Cassia crossbill (Loxia sinesciuris) in North America. We used genotyping by sequencing (GBS) to test whether three Mediterranean subspecies of common crossbills (L. curvirostra) associated with the serotinous Aleppo pine (Pinus halepensis) were more genetically distinct than European crossbills associated with nonserotinous conifers. We assembled a Cassia crossbill draft genome as a reference for mapping GBS reads and as a first step towards a more contiguous genome assembly. We found clear patterns of genetic divergence for each of the P. halepensis-associated subspecies. Geographic isolation, as promoted by resource stability and residency, is associated with genetic divergence of two of these subspecies. However, geographic isolation cannot account for divergence of L. c. hispana. Instead, resource stability likely contributed to divergence by reducing dispersal and increasing resource competition that may limit breeding by immigrants. In contrast, we found no differentiation among common crossbills associated with less stable resources, and only slight differentiation between common crossbills and parrot crossbills (L. pytyopsittacus). The substantial morphological divergence between common and parrot crossbills has likely originated or been maintained by selection despite gene flow generated by spatiotemporal resource fluctuation. Our results indicate that phenological as well as morphological characteristics of conifers have influenced crossbill diversification, and suggest a possible link between resource stability and population divergence.
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Affiliation(s)
| | - Pim Edelaar
- Department of Molecular Biology and Biochemical Engineering, University Pablo de Olavide, Seville, Spain
| | - Kathryn Uckele
- Program in Ecology, Evolution, and Conservation Biology, University of Nevada Reno, Reno, NV, USA
| | - Eduardo T Mezquida
- Department of Ecology, Faculty of Sciences, Autonomous University of Madrid, Madrid, Spain
| | - Daniel Alonso
- Department of Ornithology, Aranzadi Sciences Society, Donostia-S. Sebastián, Spain
| | - Joshua P Jahner
- Department of Biology, University of Nevada Reno, Reno, NV, USA
| | - Ron W Summers
- Royal Society for the Protection of Birds Centre for Conservation Science, North Scotland Regional Office, Inverness, UK
| | - Craig W Benkman
- Department of Zoology and Physiology, University of Wyoming, Laramie, WY, USA
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168
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Woodruff GC, Phillips PC. Field studies reveal a close relative of C. elegans thrives in the fresh figs of Ficus septica and disperses on its Ceratosolen pollinating wasps. BMC Ecol 2018; 18:26. [PMID: 30129423 PMCID: PMC6102938 DOI: 10.1186/s12898-018-0182-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 07/30/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Biotic interactions are ubiquitous and require information from ecology, evolutionary biology, and functional genetics in order to be understood. However, study systems that are amenable to investigations across such disparate fields are rare. Figs and fig wasps are a classic system for ecology and evolutionary biology with poor functional genetics; Caenorhabditis elegans is a classic system for functional genetics with poor ecology. In order to help bridge these disciplines, here we describe the natural history of a close relative of C. elegans, Caenorhabditis inopinata, that is associated with the fig Ficus septica and its pollinating Ceratosolen wasps. RESULTS To understand the natural context of fig-associated Caenorhabditis, fresh F. septica figs from four Okinawan islands were sampled, dissected, and observed under microscopy. C. inopinata was found in all islands where F. septica figs were found. C.i nopinata was routinely found in the fig interior and almost never observed on the outside surface. C. inopinata was only found in pollinated figs, and C. inopinata was more likely to be observed in figs with more foundress pollinating wasps. Actively reproducing C. inopinata dominated early phase figs, whereas late phase figs with emerging wasp progeny harbored C. inopinata dauer larvae. Additionally, C. inopinata was observed dismounting from Ceratosolen pollinating wasps that were placed on agar plates. C. inopinata was not found on non-pollinating, parasitic Philotrypesis wasps. Finally, C. inopinata was only observed in F. septica figs among five Okinawan Ficus species sampled. CONCLUSION These are the first detailed field observations of C. inopinata, and they suggest a natural history where this species proliferates in early phase F. septica figs and disperses from late phase figs on Ceratosolen pollinating fig wasps. While consistent with other examples of nematode diversification in the fig microcosm, the fig and wasp host specificity of C. inopinata is highly divergent from the life histories of its close relatives and frames hypotheses for future investigations. This natural co-occurrence of the fig/fig wasp and C. inopinata study systems sets the stage for an integrated research program that can help to explain the evolution of interspecific interactions.
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Affiliation(s)
- Gavin C Woodruff
- Forest Pathology Laboratory, Forestry and Forest Products Research Institute, Tsukuba, Japan.
- Department of Biology, Institute of Ecology and Evolution, University of Oregon, Eugene, OR, USA.
| | - Patrick C Phillips
- Department of Biology, Institute of Ecology and Evolution, University of Oregon, Eugene, OR, USA
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169
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Peona V, Weissensteiner MH, Suh A. How complete are “complete” genome assemblies?-An avian perspective. Mol Ecol Resour 2018; 18:1188-1195. [DOI: 10.1111/1755-0998.12933] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 06/11/2018] [Accepted: 07/06/2018] [Indexed: 12/26/2022]
Affiliation(s)
- Valentina Peona
- Department of Evolutionary Biology; Evolutionary Biology Centre; Uppsala University; Uppsala Sweden
| | - Matthias H. Weissensteiner
- Department of Evolutionary Biology; Evolutionary Biology Centre; Uppsala University; Uppsala Sweden
- Division of Evolutionary Biology; Faculty of Biology; Ludwig-Maximilian University of Munich; Planegg-Martinsried Germany
| | - Alexander Suh
- Department of Evolutionary Biology; Evolutionary Biology Centre; Uppsala University; Uppsala Sweden
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170
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Sutton JT, Helmkampf M, Steiner CC, Bellinger MR, Korlach J, Hall R, Baybayan P, Muehling J, Gu J, Kingan S, Masuda BM, Ryder OA. A High-Quality, Long-Read De Novo Genome Assembly to Aid Conservation of Hawaii's Last Remaining Crow Species. Genes (Basel) 2018; 9:genes9080393. [PMID: 30071683 PMCID: PMC6115840 DOI: 10.3390/genes9080393] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 07/23/2018] [Accepted: 07/27/2018] [Indexed: 11/16/2022] Open
Abstract
Genome-level data can provide researchers with unprecedented precision to examine the causes and genetic consequences of population declines, which can inform conservation management. Here, we present a high-quality, long-read, de novo genome assembly for one of the world’s most endangered bird species, the ʻAlalā (Corvus hawaiiensis; Hawaiian crow). As the only remaining native crow species in Hawaiʻi, the ʻAlalā survived solely in a captive-breeding program from 2002 until 2016, at which point a long-term reintroduction program was initiated. The high-quality genome assembly was generated to lay the foundation for both comparative genomics studies and the development of population-level genomic tools that will aid conservation and recovery efforts. We illustrate how the quality of this assembly places it amongst the very best avian genomes assembled to date, comparable to intensively studied model systems. We describe the genome architecture in terms of repetitive elements and runs of homozygosity, and we show that compared with more outbred species, the ʻAlalā genome is substantially more homozygous. We also provide annotations for a subset of immunity genes that are likely to be important in conservation management, and we discuss how this genome is currently being used as a roadmap for downstream conservation applications.
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Affiliation(s)
- Jolene T Sutton
- Department of Biology, University of Hawaii at Hilo, Hilo, HI 96720, USA.
| | - Martin Helmkampf
- Department of Biology, University of Hawaii at Hilo, Hilo, HI 96720, USA.
| | - Cynthia C Steiner
- Institute for Conservation Research, San Diego Zoo, Escondido, CA 92027, USA.
| | - M Renee Bellinger
- Department of Biology, University of Hawaii at Hilo, Hilo, HI 96720, USA.
| | | | | | | | | | - Jenny Gu
- Pacific Biosciences, Menlo Park, CA 94025, USA.
| | | | - Bryce M Masuda
- Institute for Conservation Research, San Diego Zoo Global, Volcano, HI 96785, USA.
| | - Oliver A Ryder
- Institute for Conservation Research, San Diego Zoo, Escondido, CA 92027, USA.
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171
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He Z, Li X, Yang M, Wang X, Zhong C, Duke NC, Wu CI, Shi S. Speciation with gene flow via cycles of isolation and migration: insights from multiple mangrove taxa. Natl Sci Rev 2018; 6:275-288. [PMID: 31258952 PMCID: PMC6599600 DOI: 10.1093/nsr/nwy078] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Allopatric speciation requiring an unbroken period of geographical isolation has been the standard model of neo-Darwinism. While doubts have been repeatedly raised, strict allopatry without any gene flow remains a plausible mechanism in most cases. To rigorously reject strict allopatry, genomic sequences superimposed on the geological records of a well-delineated geographical barrier are necessary. The Strait of Malacca, narrowly connecting the Pacific and Indian Ocean coasts, serves at different times either as a geographical barrier or a conduit of gene flow for coastal/marine species. We surveyed 1700 plants from 29 populations of 5 common mangrove species by large-scale DNA sequencing and added several whole-genome assemblies. Speciation between the two oceans is driven by cycles of isolation and gene flow due to the fluctuations in sea level leading to the opening/closing of the Strait to ocean currents. Because the time required for speciation in mangroves is longer than the isolation phases, speciation in these mangroves has proceeded through many cycles of mixing-isolation-mixing, or MIM, cycles. The MIM mechanism, by relaxing the condition of no gene flow, can promote speciation in many more geographical features than strict allopatry can. Finally, the MIM mechanism of speciation is also efficient, potentially yielding mn (m > 1) species after n cycles.
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Affiliation(s)
- Ziwen He
- State Key Laboratory of Biocontrol, Guangdong Key Lab of Plant Resources, Key Laboratory of Biodiversity Dynamics and Conservation of Guangdong Higher Education Institutes, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Xinnian Li
- State Key Laboratory of Biocontrol, Guangdong Key Lab of Plant Resources, Key Laboratory of Biodiversity Dynamics and Conservation of Guangdong Higher Education Institutes, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Ming Yang
- State Key Laboratory of Biocontrol, Guangdong Key Lab of Plant Resources, Key Laboratory of Biodiversity Dynamics and Conservation of Guangdong Higher Education Institutes, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Xinfeng Wang
- State Key Laboratory of Biocontrol, Guangdong Key Lab of Plant Resources, Key Laboratory of Biodiversity Dynamics and Conservation of Guangdong Higher Education Institutes, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
| | - Cairong Zhong
- Hainan Dongzhai Harbor National Nature Reserve Administration, Haikou 571129, China
| | - Norman C Duke
- Centre for Tropical Water and Aquatic Ecosystem Research, James Cook University, Townsville 4811, Australia
| | - Chung-I Wu
- State Key Laboratory of Biocontrol, Guangdong Key Lab of Plant Resources, Key Laboratory of Biodiversity Dynamics and Conservation of Guangdong Higher Education Institutes, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China.,CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China.,Department of Ecology and Evolution, University of Chicago, Chicago IL 60637, USA
| | - Suhua Shi
- State Key Laboratory of Biocontrol, Guangdong Key Lab of Plant Resources, Key Laboratory of Biodiversity Dynamics and Conservation of Guangdong Higher Education Institutes, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275, China
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172
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Bassham S, Catchen J, Lescak E, von Hippel FA, Cresko WA. Repeated Selection of Alternatively Adapted Haplotypes Creates Sweeping Genomic Remodeling in Stickleback. Genetics 2018; 209:921-939. [PMID: 29794240 PMCID: PMC6028257 DOI: 10.1534/genetics.117.300610] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2017] [Accepted: 05/21/2018] [Indexed: 01/06/2023] Open
Abstract
Heterogeneous genetic divergence can accumulate across the genome when populations adapt to different habitats while still exchanging alleles. How long does diversification take and how much of the genome is affected? When divergence occurs in parallel from standing genetic variation, how often are the same haplotypes involved? We explore these questions using restriction site-associated DNA sequencing genotyping data and show that broad-scale genomic repatterning, fueled by copious standing variation, can emerge in just dozens of generations in replicate natural populations of threespine stickleback fish (Gasterosteus aculeatus). After the catastrophic 1964 Alaskan earthquake, marine stickleback colonized newly created ponds on seismically uplifted islands. We find that freshwater fish in these young ponds differ from their marine ancestors across the same genomic segments previously shown to have diverged in much older lake populations. Outside of these core divergent regions the genome shows no population structure across the ocean-freshwater divide, consistent with strong local selection acting in alternative environments on stickleback populations still connected by significant gene flow. Reinforcing this inference, a majority of divergent haplotypes that are at high frequency in ponds are detectable in the sea, even across great geographic distances. Building upon previous population genomics work in this model species, our data suggest that a long history of divergent selection and gene flow among stickleback populations in oceanic and freshwater habitats has maintained polymorphisms of alternatively adapted DNA sequences that facilitate parallel evolution.
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Affiliation(s)
- Susan Bassham
- Institute of Ecology and Evolution, University of Oregon, Eugene, Oregon 97403
| | - Julian Catchen
- Department of Animal Biology, University of Illinois at Urbana-Champaign, Illinois 61801
| | - Emily Lescak
- Department of Biological Sciences, University of Alaska Anchorage, Alaska 99508
- College of Fisheries and Ocean Science, University of Alaska Fairbanks, Alaska 99775
| | - Frank A von Hippel
- Department of Biological Sciences , Northern Arizona University, Flagstaff, Arizona 86011
- Center for Bioengineering Innovation, Northern Arizona University, Flagstaff, Arizona 86011
| | - William A Cresko
- Institute of Ecology and Evolution, University of Oregon, Eugene, Oregon 97403
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173
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Sohn JI, Nam K, Hong H, Kim JM, Lim D, Lee KT, Do YJ, Cho CY, Kim N, Chai HH, Nam JW. Whole genome and transcriptome maps of the entirely black native Korean chicken breed Yeonsan Ogye. Gigascience 2018; 7:5052204. [PMID: 30010758 PMCID: PMC6065499 DOI: 10.1093/gigascience/giy086] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 05/19/2018] [Accepted: 07/04/2018] [Indexed: 12/30/2022] Open
Abstract
Background Yeonsan Ogye (YO), an indigenous Korean chicken breed (Gallus gallus domesticus), has entirely black external features and internal organs. In this study, the draft genome of YO was assembled using a hybrid de novo assembly method that takes advantage of high-depth Illumina short reads (376.6X) and low-depth Pacific Biosciences (PacBio) long reads (9.7X). Findings The contig and scaffold NG50s of the hybrid de novo assembly were 362.3 Kbp and 16.8 Mbp, respectively. The completeness (97.6%) of the draft genome (Ogye_1.1) was evaluated with single-copy orthologous genes using Benchmarking Universal Single-Copy Orthologs and found to be comparable to the current chicken reference genome (galGal5; 97.4%; contigs were assembled with high-depth PacBio long reads (50X) and scaffolded with short reads) and superior to other avian genomes (92%-93%; assembled with short read-only or hybrid methods). Compared to galGal4 and galGal5, the draft genome included 551 structural variations including the fibromelanosis (FM) locus duplication, related to hyperpigmentation. To comprehensively reconstruct transcriptome maps, RNA sequencing and reduced representation bisulfite sequencing data were analyzed from 20 tissues, including 4 black tissues (skin, shank, comb, and fascia). The maps included 15,766 protein-coding and 6,900 long noncoding RNA genes, many of which were tissue-specifically expressed and displayed tissue-specific DNA methylation patterns in the promoter regions. Conclusions We expect that the resulting genome sequence and transcriptome maps will be valuable resources for studying domestic chicken breeds, including black-skinned chickens, as well as for understanding genomic differences between breeds and the evolution of hyperpigmented chickens and functional elements related to hyperpigmentation.
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Affiliation(s)
- Jang-il Sohn
- Department of Life Science, Hanyang University, Seoul, 133-791, Republic of Korea
- Research Institute for Convergence of Basic Sciences, Hanyang University, Seoul, 133-791, Republic of Korea
| | - Kyoungwoo Nam
- Department of Life Science, Hanyang University, Seoul, 133-791, Republic of Korea
| | - Hyosun Hong
- Department of Life Science, Hanyang University, Seoul, 133-791, Republic of Korea
| | - Jun-Mo Kim
- Department of Animal Science and Technology, Chung-Ang University, Anseong, Gyeonggi-do, 17546, Republic of Korea
| | - Dajeong Lim
- Department of Animal Biotechnology & Environment, National Institute of Animal Science, RDA, Wanju, 55365, Republic of Korea
| | - Kyung-Tai Lee
- Department of Animal Biotechnology & Environment, National Institute of Animal Science, RDA, Wanju, 55365, Republic of Korea
| | - Yoon Jung Do
- Department of Animal Biotechnology & Environment, National Institute of Animal Science, RDA, Wanju, 55365, Republic of Korea
| | - Chang Yeon Cho
- Animal Genetic Resource Research Center, National Institute of Animal Science, RDA, Namwon, 55717, Republic of Korea
| | - Namshin Kim
- Personalized Genomic Medicine Research Center, KRIBB, Daejeon, 34141, Republic of Korea
| | - Han-Ha Chai
- Department of Animal Biotechnology & Environment, National Institute of Animal Science, RDA, Wanju, 55365, Republic of Korea
- College of Pharmacy, Chonnam National University, Kwangju, 61186, Republic of Korea
| | - Jin-Wu Nam
- Department of Life Science, Hanyang University, Seoul, 133-791, Republic of Korea
- Research Institute for Convergence of Basic Sciences, Hanyang University, Seoul, 133-791, Republic of Korea
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174
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Semenov GA, Koblik EA, Red'kin YA, Badyaev AV. Extensive phenotypic diversification coexists with little genetic divergence and a lack of population structure in the White Wagtail subspecies complex (Motacilla alba). J Evol Biol 2018; 31:1093-1108. [PMID: 29873425 DOI: 10.1111/jeb.13305] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Revised: 03/27/2018] [Accepted: 05/28/2018] [Indexed: 02/01/2023]
Abstract
Geographically clustered phenotypes often demonstrate consistent patterns in molecular markers, particularly mitochondrial DNA (mtDNA) traditionally used in phylogeographic studies. However, distinct evolutionary trajectories among traits and markers can lead to their discordance. First, geographic structure in phenotypic traits and nuclear molecular markers can be co-aligned but inconsistent with mtDNA (mito-nuclear discordance). Alternatively, phenotypic variation can have little to do with patterns in neither mtDNA nor nuclear markers. Disentangling between these distinct patterns can provide insight into the role of selection, demography and gene flow in population divergence. Here, we examined a previously reported case of strong inconsistency between geographic structure in mtDNA and plumage traits in a widespread polytypic bird species, the White Wagtail (Motacilla alba). We tested whether this pattern is due to mito-nuclear discordance or discrepancy between morphological evolution and both nuclear and mtDNA markers. We analysed population differentiation and structure across six out of nine commonly recognized subspecies using 17 microsatellite loci and a combination of microsatellites and plumage indices in a comprehensively sampled region of a contact between two subspecies. We did not find support for the mito-nuclear discordance hypothesis: nuclear markers indicated a subtle signal of genetic clustering only partially consistent with plumage groups, similar to previous findings that relied on mtDNA. We discuss evolutionary factors that could have shaped the intricate patterns of phenotypic diversification in the White wagtail and the role that repeated selection on plumage 'hotspots' and hybridization may have played.
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Affiliation(s)
- Georgy A Semenov
- Department of Ecology & Evolutionary Biology, University of Colorado, Boulder, CO, USA.,Department of Ecology & Evolutionary Biology, University of Arizona, Tucson, AZ, USA.,Institute of Systematics and Ecology of Animals, Novosibirsk, Russia
| | - Evgeniy A Koblik
- Department of Ornithology, Zoological Museum of Moscow State University, Moscow, Russia
| | - Yaroslav A Red'kin
- Department of Ornithology, Zoological Museum of Moscow State University, Moscow, Russia
| | - Alexander V Badyaev
- Department of Ecology & Evolutionary Biology, University of Arizona, Tucson, AZ, USA
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175
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Jones MR, Mills LS, Alves PC, Callahan CM, Alves JM, Lafferty DJR, Jiggins FM, Jensen JD, Melo-Ferreira J, Good JM. Adaptive introgression underlies polymorphic seasonal camouflage in snowshoe hares. Science 2018; 360:1355-1358. [DOI: 10.1126/science.aar5273] [Citation(s) in RCA: 182] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Accepted: 05/01/2018] [Indexed: 12/14/2022]
Abstract
Snowshoe hares (Lepus americanus) maintain seasonal camouflage by molting to a white winter coat, but some hares remain brown during the winter in regions with low snow cover. We show that cis-regulatory variation controlling seasonal expression of the Agouti gene underlies this adaptive winter camouflage polymorphism. Genetic variation at Agouti clustered by winter coat color across multiple hare and jackrabbit species, revealing a history of recurrent interspecific gene flow. Brown winter coats in snowshoe hares likely originated from an introgressed black-tailed jackrabbit allele that has swept to high frequency in mild winter environments. These discoveries show that introgression of genetic variants that underlie key ecological traits can seed past and ongoing adaptation to rapidly changing environments.
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176
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Tritsch C, Stuckas H, Martens J, Pentzold S, Kvist L, Lo Valvo M, Giacalone G, Tietze DT, Nazarenko AA, PÄckert M. Gene flow in the European coal tit, Periparus ater (Aves: Passeriformes): low among Mediterranean populations but high in a continental contact zone. Biol J Linn Soc Lond 2018. [DOI: 10.1093/biolinnean/bly043] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Christian Tritsch
- Senckenberg Natural History Collections, Königsbrücker Landstraße, Dresden, Germany
- Institute of Biology, Molecular Evolution & Animal Systematics, University of Leipzig, Leipzig, Germany
| | - Heiko Stuckas
- Senckenberg Natural History Collections, Königsbrücker Landstraße, Dresden, Germany
| | - Jochen Martens
- Institute of Organismic and Molecular Evolution, Johannes Gutenberg University, Mainz, Germany
| | - Stefan Pentzold
- Institute of Biology, Molecular Evolution & Animal Systematics, University of Leipzig, Leipzig, Germany
- Max Planck Institute for Chemical Ecology, Jena, Germany
| | - Laura Kvist
- Department of Ecology and Genetics, University of Oulu, Oulu, Finland
| | - Mario Lo Valvo
- Dipartimento di Scienze e Tecnologie biologiche, chimiche e farmaceutiche, Via Archirafi, Palermo, Italy
| | | | | | - Alexander A Nazarenko
- Federal Scientific Center of the East Asia Terrestrial Biodiversity, Far Eastern Branch of the Russian Academy of Sciences, Vladivostok, Russia
| | - Martin PÄckert
- Senckenberg Natural History Collections, Königsbrücker Landstraße, Dresden, Germany
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177
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Campagna L, Rodriguez P, Mazzulla JC. Transgressive phenotypes and evidence of weak postzygotic isolation in F1 hybrids between closely related capuchino seedeaters. PLoS One 2018; 13:e0199113. [PMID: 29902247 PMCID: PMC6002061 DOI: 10.1371/journal.pone.0199113] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 05/31/2018] [Indexed: 11/18/2022] Open
Abstract
Postzygotic reproductive isolation may become strong only once the process of speciation is in its advanced stages. For taxa in the early stages of speciation, prezygotic reproductive isolation barriers may play a predominant role in maintaining species boundaries. Here, we study the recent capuchino seedeater biological radiation, a group of highly sympatric species from the genus Sporophila that have diversified during the Pleistocene in Neotropical grasslands. Capuchinos can be diagnosed by adult male coloration patterns and song, two sets of characters known to contribute to pre-mating reproductive isolation. However, it remains unknown whether potzygotic incompatibilities contribute to maintaining species limits in this group. Here we use existing breeding records from captive individuals to test for patterns consistent with F1 inviability. We compare hatching success, fledging success, and the sex ratio at adulthood between conspecific and hybrid capuchino pairs. We observed a trend towards lower numbers of the heterogametic sex among adult hybrids, consistent Haldane's rule, but this was supported by only one of our statistical tests. Our study is the first to document hybrid male capuchino phenotypes based on known crosses. We observed phenotypes that were similar or intermediate to those of the parental species, as well as novel plumage patterns that have not been described in the wild. One cross produced a plumage pattern that has been observed at low frequencies in natural populations. We discuss the implications of our results for understanding the relative importance of the mechanisms of reproductive isolation in capuchino seedeaters.
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Affiliation(s)
- Leonardo Campagna
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, United States of America
- Fuller Evolutionary Biology Program, Cornell Lab of Ornithology, Cornell University, Ithaca, NY, United States of America
- * E-mail:
| | - Pablo Rodriguez
- Federación Ornitológica Argentina, Virrey Liniers, Ciudad Autónoma de Buenos Aires, Argentina
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178
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Roesti M. Varied Genomic Responses to Maladaptive Gene Flow and Their Evidence. Genes (Basel) 2018; 9:E298. [PMID: 29899287 PMCID: PMC6027369 DOI: 10.3390/genes9060298] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Revised: 05/17/2018] [Accepted: 05/30/2018] [Indexed: 12/02/2022] Open
Abstract
Adaptation to a local environment often occurs in the face of maladaptive gene flow. In this perspective, I discuss several ideas on how a genome may respond to maladaptive gene flow during adaptation. On the one hand, selection can build clusters of locally adaptive alleles at fortuitously co-localized loci within a genome, thereby facilitating local adaptation with gene flow ('allele-only clustering'). On the other hand, the selective pressure to link adaptive alleles may drive co-localization of the actual loci relevant for local adaptation within a genome through structural genome changes or an evolving intra-genomic crossover rate ('locus clustering'). While the expected outcome is, in both cases, a higher frequency of locally adaptive alleles in some genome regions than others, the molecular units evolving in response to gene flow differ (i.e., alleles versus loci). I argue that, although making this distinction is important, we commonly lack the critical empirical evidence to do so. This is mainly because many current approaches are biased towards detecting local adaptation in genome regions with low crossover rates. The importance of low-crossover genome regions for adaptation with gene flow, such as in co-localizing relevant loci within a genome, thus remains unclear. Future empirical investigations should address these questions by making use of comparative genomics, where multiple de novo genome assemblies from species evolved under different degrees of genetic exchange are compared. This research promises to advance our understanding of how a genome adapts to maladaptive gene flow, thereby promoting adaptive divergence and reproductive isolation.
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Affiliation(s)
- Marius Roesti
- Biodiversity Research Centre and Zoology Department, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada.
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179
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Campbell CR, Poelstra JW, Yoder AD. What is Speciation Genomics? The roles of ecology, gene flow, and genomic architecture in the formation of species. Biol J Linn Soc Lond 2018. [DOI: 10.1093/biolinnean/bly063] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Affiliation(s)
| | - J W Poelstra
- Department of Biology, Duke University, Durham, NC, USA
| | - Anne D Yoder
- Department of Biology, Duke University, Durham, NC, USA
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180
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Nigenda‐Morales SF, Hu Y, Beasley JC, Ruiz‐Piña HA, Valenzuela‐Galván D, Wayne RK. Transcriptomic analysis of skin pigmentation variation in the Virginia opossum (
Didelphis virginiana
). Mol Ecol 2018; 27:2680-2697. [DOI: 10.1111/mec.14712] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Revised: 04/05/2018] [Accepted: 04/17/2018] [Indexed: 12/19/2022]
Affiliation(s)
- Sergio F. Nigenda‐Morales
- Department of Ecology and Evolutionary Biology University of California, Los Angeles Los Angeles California
| | - Yibo Hu
- Key Lab of Animal Ecology and Conservation Biology Institute of Zoology Chinese Academy of Sciences Chaoyang, Beijing China
| | - James C. Beasley
- Savannah River Ecology Lab Warnell School of Forestry and Natural Resources University of Georgia Aiken South Carolina
| | - Hugo A. Ruiz‐Piña
- Centro de Investigaciones Regionales “Dr. Hideyo Noguchi” Universidad Autónoma de Yucatán Mérida Yucatán Mexico
| | - David Valenzuela‐Galván
- Departamento de Ecología Evolutiva Centro de Investigación en Biodiversidad y Conservación Universidad Autónoma del Estado de Morelos Cuernavaca Morelos Mexico
| | - Robert K. Wayne
- Department of Ecology and Evolutionary Biology University of California, Los Angeles Los Angeles California
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181
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Brelsford A, Toews DPL, Irwin DE. Admixture mapping in a hybrid zone reveals loci associated with avian feather coloration. Proc Biol Sci 2018; 284:rspb.2017.1106. [PMID: 29118129 DOI: 10.1098/rspb.2017.1106] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 10/10/2017] [Indexed: 12/30/2022] Open
Abstract
Identifying the genetic bases for colour patterns has provided important insights into the control and expression of pigmentation and how these characteristics influence fitness. However, much more is known about the genetic bases for traits based on melanin pigments than for traits based on another major class of pigments, carotenoids. Here, we use natural admixture in a hybrid zone between Audubon's and myrtle warblers (Setophaga coronata auduboni/S. c. coronata) to identify genomic regions associated with both types of pigmentation. Warblers are known for rapid speciation and dramatic differences in plumage. For each of five plumage coloration traits, we found highly significant associations with multiple single-nucleotide polymorphisms (SNPs) across the genome and these were clustered in discrete regions. Regions near significantly associated SNPs were enriched for genes associated with keratin filaments, fibrils that make up feathers. A carotenoid-based trait that differs between the taxa-throat colour-had more than a dozen genomic regions of association. One cluster of SNPs for this trait overlaps the Scavenger Receptor Class F Member 2 (SCARF2) gene. Other scavenger receptors are presumed to be expressed at target tissues and involved in the selective movement of carotenoids into the target cells, making SCARF2 a plausible new candidate for carotenoid processing. In addition, two melanin-based plumage traits-colours of the eye line and eye spot-show very strong associations with a single genomic region mapping to chromosome 20 in the zebra finch. These findings indicate that only a subset of the genomic regions differentiated between these two warblers are associated with the plumage differences between them and demonstrate the utility of reduced-representation genomic scans in hybrid zones.
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Affiliation(s)
- Alan Brelsford
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, 6270 University Boulevard, Vancouver, British Columbia, Canada V6T 1Z4.,Department of Ecology and Evolution, University of Lausanne, 1015 Lausanne, Switzerland.,Evolution, Ecology, and Organismal Biology Department, University of California Riverside, Riverside, CA, 92521, USA
| | - David P L Toews
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, 6270 University Boulevard, Vancouver, British Columbia, Canada V6T 1Z4 .,Fuller Evolutionary Biology Program, Cornell Lab of Ornithology, Cornell University, 159 Sapsucker Woods Road, Ithaca, NY 14850, USA
| | - Darren E Irwin
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, 6270 University Boulevard, Vancouver, British Columbia, Canada V6T 1Z4
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182
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Wang GD, Zhang BL, Zhou WW, Li YX, Jin JQ, Shao Y, Yang HC, Liu YH, Yan F, Chen HM, Jin L, Gao F, Zhang Y, Li H, Mao B, Murphy RW, Wake DB, Zhang YP, Che J. Selection and environmental adaptation along a path to speciation in the Tibetan frog Nanorana parkeri. Proc Natl Acad Sci U S A 2018; 115:E5056-E5065. [PMID: 29760079 PMCID: PMC5984489 DOI: 10.1073/pnas.1716257115] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Tibetan frogs, Nanorana parkeri, are differentiated genetically but not morphologically along geographical and elevational gradients in a challenging environment, presenting a unique opportunity to investigate processes leading to speciation. Analyses of whole genomes of 63 frogs reveal population structuring and historical demography, characterized by highly restricted gene flow in a narrow geographic zone lying between matrilines West (W) and East (E). A population found only along a single tributary of the Yalu Zangbu River has the mitogenome only of E, whereas nuclear genes of W comprise 89-95% of the nuclear genome. Selection accounts for 579 broadly scattered, highly divergent regions (HDRs) of the genome, which involve 365 genes. These genes fall into 51 gene ontology (GO) functional classes, 14 of which are likely to be important in driving reproductive isolation. GO enrichment analyses of E reveal many overrepresented functional categories associated with adaptation to high elevations, including blood circulation, response to hypoxia, and UV radiation. Four genes, including DNAJC8 in the brain, TNNC1 and ADORA1 in the heart, and LAMB3 in the lung, differ in levels of expression between low- and high-elevation populations. High-altitude adaptation plays an important role in maintaining and driving continuing divergence and reproductive isolation. Use of total genomes enabled recognition of selection and adaptation in and between populations, as well as documentation of evolution along a stepped cline toward speciation.
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Affiliation(s)
- Guo-Dong Wang
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
- Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming 650223, China
| | - Bao-Lin Zhang
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
- Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming 650204, Yunnan, China
| | - Wei-Wei Zhou
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
- Southeast Asia Biodiversity Research Institute, Chinese Academy of Sciences, Yezin, 05282 Nay Pyi Taw, Myanmar
| | - Yong-Xin Li
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
- Kunming College of Life Science, University of Chinese Academy of Sciences, Kunming 650204, Yunnan, China
| | - Jie-Qiong Jin
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
| | - Yong Shao
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
| | - He-Chuan Yang
- Human Genetics, Genome Institute of Singapore, Agency for Science, Technology and Research, Singapore 138672, Singapore
| | - Yan-Hu Liu
- Laboratory for Conservation and Utilization of Bio-Resources & Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming 650091, China
| | - Fang Yan
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
| | - Hong-Man Chen
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
| | - Li Jin
- Key Laboratory of Freshwater Fish Reproduction and Development of the Ministry of Education and Key Laboratory of Aquatic Science of Chongqing, Southwest University School of Life Sciences, Chongqing 400715, China
| | - Feng Gao
- CAS Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Yaoguang Zhang
- Key Laboratory of Freshwater Fish Reproduction and Development of the Ministry of Education and Key Laboratory of Aquatic Science of Chongqing, Southwest University School of Life Sciences, Chongqing 400715, China
| | - Haipeng Li
- Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming 650223, China
- CAS Key Laboratory of Computational Biology, CAS-MPG Partner Institute for Computational Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Bingyu Mao
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
- Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming 650223, China
| | - Robert W Murphy
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
- Centre for Biodiversity and Conservation Biology, Royal Ontario Museum, Toronto, ON, Canada M5S 2C6
| | - David B Wake
- Department of Integrative Biology and Museum of Vertebrate Zoology, University of California, Berkeley, CA 94720-3160
| | - Ya-Ping Zhang
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China;
- Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming 650223, China
| | - Jing Che
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China;
- Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming 650223, China
- Southeast Asia Biodiversity Research Institute, Chinese Academy of Sciences, Yezin, 05282 Nay Pyi Taw, Myanmar
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183
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Schirrmann MK, Zoller S, Croll D, Stukenbrock EH, Leuchtmann A, Fior S. Genomewide signatures of selection in Epichloë reveal candidate genes for host specialization. Mol Ecol 2018; 27:3070-3086. [PMID: 29633410 DOI: 10.1111/mec.14585] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 02/21/2018] [Accepted: 02/23/2018] [Indexed: 12/31/2022]
Abstract
Host specialization is a key process in ecological divergence and speciation of plant-associated fungi. The underlying determinants of host specialization are generally poorly understood, especially in endophytes, which constitute one of the most abundant components of the plant microbiome. We addressed the genetic basis of host specialization in two sympatric subspecies of grass-endophytic fungi from the Epichloë typhina complex: subsp. typhina and clarkii. The life cycle of these fungi entails unrestricted dispersal of gametes and sexual reproduction before infection of a new host, implying that the host imposes a selective barrier on viability of the progeny. We aimed to detect genes under divergent selection between subspecies, experiencing restricted gene flow due to adaptation to different hosts. Using pooled whole-genome sequencing data, we combined FST and DXY population statistics in genome scans and detected 57 outlier genes showing strong differentiation between the two subspecies. Genomewide analyses of nucleotide diversity (π), Tajima's D and dN/dS ratios indicated that these genes have evolved under positive selection. Genes encoding secreted proteins were enriched among the genes showing evidence of positive selection, suggesting that molecular plant-fungus interactions are strong drivers of endophyte divergence. We focused on five genes encoding secreted proteins, which were further sequenced in 28 additional isolates collected across Europe to assess genetic variation in a larger sample size. Signature of positive selection in these isolates and putative identification of pathogenic function supports our findings that these genes represent strong candidates for host specialization determinants in Epichloë endophytes. Our results highlight the role of secreted proteins as key determinants of host specialization.
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Affiliation(s)
- Melanie K Schirrmann
- Institute of Integrative Biology (IBZ), ETH Zürich, Zürich, Switzerland.,Research Group Molecular Diagnostics, Genomics and Bioinformatics, Agroscope, Wädenswil, Switzerland
| | - Stefan Zoller
- Genetic Diversity Centre (GDC), ETH Zürich, Zürich, Switzerland
| | - Daniel Croll
- Laboratory of Evolutionary Genetics, Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland
| | - Eva H Stukenbrock
- Environmental Genomics, Christian-Albrechts University of Kiel, Kiel, Germany.,Max Planck Institute for Evolutionary Biology, Plön, Germany
| | - Adrian Leuchtmann
- Institute of Integrative Biology (IBZ), ETH Zürich, Zürich, Switzerland
| | - Simone Fior
- Institute of Integrative Biology (IBZ), ETH Zürich, Zürich, Switzerland
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184
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Van Belleghem SM, Baquero M, Papa R, Salazar C, McMillan WO, Counterman BA, Jiggins CD, Martin SH. Patterns of Z chromosome divergence among Heliconius species highlight the importance of historical demography. Mol Ecol 2018; 27:3852-3872. [PMID: 29569384 PMCID: PMC6151167 DOI: 10.1111/mec.14560] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 02/14/2018] [Accepted: 02/20/2018] [Indexed: 12/31/2022]
Abstract
Sex chromosomes are disproportionately involved in reproductive isolation and adaptation. In support of such a “large‐X” effect, genome scans between recently diverged populations and species pairs often identify distinct patterns of divergence on the sex chromosome compared to autosomes. When measures of divergence between populations are higher on the sex chromosome compared to autosomes, such patterns could be interpreted as evidence for faster divergence on the sex chromosome, that is “faster‐X”, barriers to gene flow on the sex chromosome. However, demographic changes can strongly skew divergence estimates and are not always taken into consideration. We used 224 whole‐genome sequences representing 36 populations from two Heliconius butterfly clades (H. erato and H. melpomene) to explore patterns of Z chromosome divergence. We show that increased divergence compared to equilibrium expectations can in many cases be explained by demographic change. Among Heliconius erato populations, for instance, population size increase in the ancestral population can explain increased absolute divergence measures on the Z chromosome compared to the autosomes, as a result of increased ancestral Z chromosome genetic diversity. Nonetheless, we do identify increased divergence on the Z chromosome relative to the autosomes in parapatric or sympatric species comparisons that imply postzygotic reproductive barriers. Using simulations, we show that this is consistent with reduced gene flow on the Z chromosome, perhaps due to greater accumulation of incompatibilities. Our work demonstrates the importance of taking demography into account to interpret patterns of divergence on the Z chromosome, but nonetheless provides evidence to support the Z chromosome as a strong barrier to gene flow in incipient Heliconius butterfly species.
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Affiliation(s)
- Steven M Van Belleghem
- Department of Zoology, University of Cambridge, Cambridge, UK.,Department of Biological Sciences, Mississippi State University, Mississippi State, MS, USA.,Department of Biology, Center for Applied Tropical Ecology and Conservation, University of Puerto Rico, Rio Piedras, Puerto Rico.,Smithsonian Tropical Research Institute, Apartado, Panamá, Panama
| | - Margarita Baquero
- Department of Biological Sciences, Mississippi State University, Mississippi State, MS, USA
| | - Riccardo Papa
- Department of Biology, Center for Applied Tropical Ecology and Conservation, University of Puerto Rico, Rio Piedras, Puerto Rico
| | - Camilo Salazar
- Biology Program, Faculty of Natural Sciences and Mathematics, Universidad del Rosario, Carrera, Bogota, Colombia
| | - W Owen McMillan
- Smithsonian Tropical Research Institute, Apartado, Panamá, Panama
| | - Brian A Counterman
- Department of Biological Sciences, Mississippi State University, Mississippi State, MS, USA
| | - Chris D Jiggins
- Department of Zoology, University of Cambridge, Cambridge, UK
| | - Simon H Martin
- Department of Zoology, University of Cambridge, Cambridge, UK
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185
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Ortego J, Gugger PF, Sork VL. Genomic data reveal cryptic lineage diversification and introgression in Californian golden cup oaks (section Protobalanus). THE NEW PHYTOLOGIST 2018; 218:804-818. [PMID: 29274282 DOI: 10.1111/nph.14951] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 11/14/2017] [Indexed: 05/15/2023]
Abstract
Here we study hybridization, introgression and lineage diversification in the widely distributed canyon live oak (Quercus chrysolepis) and the relict island oak (Q. tomentella), two Californian golden cup oaks with an intriguing biogeographical history. We employed restriction-site-associated DNA sequencing and integrated phylogenomic and population genomic analyses to study hybridization and reconstruct the evolutionary past of these taxa. Our analyses revealed the presence of two cryptic lineages within Q. chrysolepis. One of these lineages shares its most recent common ancestor with Q. tomentella, supporting the paraphyly of Q. chrysolepis. The split of these lineages was estimated to take place during the late Pliocene or the early Pleistocene, a time corresponding well with the common presence of Q. tomentella in the fossil records of continental California. Analyses also revealed historical hybridization among lineages, high introgression from Q. tomentella into Q. chrysolepis in their current area of sympatry, and widespread admixture between the two lineages of Q. chrysolepis in contact zones. Our results support that the two lineages of Q. chrysolepis behave as a single functional species phenotypically and ecologically well differentiated from Q. tomentella, a situation that can be only accommodated considering hybridization and speciation as a continuum with diffuse limits.
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Affiliation(s)
- Joaquín Ortego
- Department of Integrative Ecology, Estación Biológica de Doñana, EBD-CSIC, Avda. Américo Vespucio 26, Seville, E-41092, Spain
| | - Paul F Gugger
- Appalachian Laboratory, University of Maryland Center for Environmental Science, 301 Braddock Road, Frostburg, MD, 21532, USA
| | - Victoria L Sork
- Department of Ecology and Evolutionary Biology, University of California, Box 957239, Los Angeles, CA, 90095, USA
- Institute of the Environment and Sustainability, University of California, Box 951496, Los Angeles, CA, 90095-1496, USA
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186
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McGirr JA, Martin CH. Parallel evolution of gene expression between trophic specialists despite divergent genotypes and morphologies. Evol Lett 2018; 2:62-75. [PMID: 30283665 PMCID: PMC6089502 DOI: 10.1002/evl3.41] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 12/22/2017] [Accepted: 01/03/2018] [Indexed: 12/20/2022] Open
Abstract
Parallel evolution of gene expression commonly underlies convergent niche specialization, but parallel changes in expression could also underlie divergent specialization. We investigated divergence in gene expression and whole-genome genetic variation across three sympatric Cyprinodon pupfishes endemic to San Salvador Island, Bahamas. This recent radiation consists of a generalist and two derived specialists adapted to novel niches: a scale-eating and a snail-eating pupfish. We sampled total mRNA from all three species at two early developmental stages and compared gene expression with whole-genome genetic differentiation among all three species in 42 resequenced genomes. Eighty percent of genes that were differentially expressed between snail-eaters and generalists were up or down regulated in the same direction between scale-eaters and generalists; however, there were no fixed variants shared between species underlying these parallel changes in expression. Genes showing parallel evolution of expression were enriched for effects on metabolic processes, whereas genes showing divergent expression were enriched for effects on cranial skeleton development and pigment biosynthesis, reflecting the most divergent phenotypes observed between specialist species. Our findings reveal that even divergent niche specialists may exhibit convergent adaptation to higher trophic levels through shared genetic pathways. This counterintuitive result suggests that parallel evolution in gene expression can accompany divergent ecological speciation during adaptive radiation.
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Affiliation(s)
- Joseph A. McGirr
- Department of BiologyUniversity of North Carolina at Chapel HillChapel HillNorth Carolina27514
| | - Christopher H. Martin
- Department of BiologyUniversity of North Carolina at Chapel HillChapel HillNorth Carolina27514
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187
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Irwin DE. Sex chromosomes and speciation in birds and other ZW systems. Mol Ecol 2018; 27:3831-3851. [PMID: 29443419 DOI: 10.1111/mec.14537] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Revised: 02/03/2018] [Accepted: 02/06/2018] [Indexed: 01/01/2023]
Abstract
Theory and empirical patterns suggest a disproportionate role for sex chromosomes in evolution and speciation. Focusing on ZW sex determination (females ZW, males ZZ; the system in birds, many snakes, and lepidopterans), I review how evolutionary dynamics are expected to differ between the Z, W and the autosomes, discuss how these differences may lead to a greater role of the sex chromosomes in speciation and use data from birds to compare relative evolutionary rates of sex chromosomes and autosomes. Neutral mutations, partially or completely recessive beneficial mutations, and deleterious mutations under many conditions are expected to accumulate faster on the Z than on autosomes. Sexually antagonistic polymorphisms are expected to arise on the Z, raising the possibility of the spread of preference alleles. The faster accumulation of many types of mutations and the potential for complex evolutionary dynamics of sexually antagonistic traits and preferences contribute to a role for the Z chromosome in speciation. A quantitative comparison among a wide variety of bird species shows that the Z tends to have less within-population diversity and greater between-species differentiation than the autosomes, likely due to both adaptive evolution and a greater rate of fixation of deleterious alleles. The W chromosome also shows strong potential to be involved in speciation, in part because of its co-inheritance with the mitochondrial genome. While theory and empirical evidence suggest a disproportionate role for sex chromosomes in speciation, the importance of sex chromosomes is moderated by their small size compared to the whole genome.
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Affiliation(s)
- Darren E Irwin
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, Canada
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188
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Discordance between genomic divergence and phenotypic variation in a rapidly evolving avian genus (Motacilla). Mol Phylogenet Evol 2018; 120:183-195. [DOI: 10.1016/j.ympev.2017.11.020] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Revised: 11/10/2017] [Accepted: 11/29/2017] [Indexed: 01/23/2023]
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189
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Cahill JA, Heintzman PD, Harris K, Teasdale MD, Kapp J, Soares AER, Stirling I, Bradley D, Edwards CJ, Graim K, Kisleika AA, Malev AV, Monaghan N, Green RE, Shapiro B. Genomic Evidence of Widespread Admixture from Polar Bears into Brown Bears during the Last Ice Age. Mol Biol Evol 2018; 35:1120-1129. [DOI: 10.1093/molbev/msy018] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Affiliation(s)
- James A Cahill
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA
| | - Peter D Heintzman
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA
- Tromsø University Museum, UiT – The Arctic University of Norway, Tromsø, Norway
| | - Kelley Harris
- Department of Genetics, Stanford University, Stanford, CA
| | - Matthew D Teasdale
- Smurfit Institute of Genetics, Dublin 2, Ireland
- BioArCh, University of York, York, United Kingdom
| | - Joshua Kapp
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA
| | - Andre E R Soares
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA
| | - Ian Stirling
- Wildlife Research Division, Department of Environment, c/o Department of Biological Sciences, University of Alberta, Edmonton, AB
- Department of Biological Sciences, University of Alberta, Edmonton, AB
| | | | - Ceiridwen J Edwards
- Department of Biological Sciences, School of Applied Sciences, University of Huddersfield, Queensgate, Huddersfield, United Kingdom
| | - Kiley Graim
- Lewis-Sigler Institute for Integrative Genomics, Princeton University, NJ
- Flatiron Institute, Simons Foundation, New York, NY
| | | | | | - Nigel Monaghan
- National Museum of Ireland – Natural History, Dublin, Ireland
| | - Richard E Green
- Department of Biomolecular Engineering, University of California, Santa Cruz, Santa Cruz, CA
- UCSC Genomics Institute, University of California, Santa Cruz, Santa Cruz, CA
| | - Beth Shapiro
- Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, Santa Cruz, CA
- UCSC Genomics Institute, University of California, Santa Cruz, Santa Cruz, CA
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190
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Rafati N, Blanco-Aguiar JA, Rubin CJ, Sayyab S, Sabatino SJ, Afonso S, Feng C, Alves PC, Villafuerte R, Ferrand N, Andersson L, Carneiro M. A genomic map of clinal variation across the European rabbit hybrid zone. Mol Ecol 2018; 27:1457-1478. [PMID: 29359877 DOI: 10.1111/mec.14494] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 12/03/2017] [Accepted: 12/04/2017] [Indexed: 01/02/2023]
Abstract
Speciation is a process proceeding from weak to complete reproductive isolation. In this continuum, naturally hybridizing taxa provide a promising avenue for revealing the genetic changes associated with the incipient stages of speciation. To identify such changes between two subspecies of rabbits that display partial reproductive isolation, we studied patterns of allele frequency change across their hybrid zone using whole-genome sequencing. To connect levels and patterns of genetic differentiation with phenotypic manifestations of subfertility in hybrid rabbits, we further investigated patterns of gene expression in testis. Geographic cline analysis revealed 253 regions characterized by steep changes in allele frequency across their natural region of contact. This catalog of regions is likely to be enriched for loci implicated in reproductive barriers and yielded several insights into the evolution of hybrid dysfunction in rabbits: (i) incomplete reproductive isolation is likely governed by the effects of many loci, (ii) protein-protein interaction analysis suggest that genes within these loci interact more than expected by chance, (iii) regulatory variation is likely the primary driver of incompatibilities, and (iv) large chromosomal rearrangements appear not to be a major mechanism underlying incompatibilities or promoting isolation in the face of gene flow. We detected extensive misregulation of gene expression in testis of hybrid males, but not a statistical overrepresentation of differentially expressed genes in candidate regions. Our results also did not support an X chromosome-wide disruption of expression as observed in mice and cats, suggesting variation in the mechanistic basis of hybrid male reduced fertility among mammals.
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Affiliation(s)
- Nima Rafati
- Science for Life Laboratory Uppsala, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden.,Science for Life Laboratory Uppsala, Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
| | - José A Blanco-Aguiar
- CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, Vairão, Portugal.,Instituto de Investigacion en Recursos Cinegéticos (IREC-CSIC-UCLM-JCCM), Ciudad Real, Spain
| | - Carl J Rubin
- Science for Life Laboratory Uppsala, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Shumaila Sayyab
- Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, Uppsala, Sweden.,Research Center for Modeling and Simulation, National University of Sciences and Technology, Islamabad, Pakistan
| | - Stephen J Sabatino
- CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, Vairão, Portugal
| | - Sandra Afonso
- CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, Vairão, Portugal
| | - Chungang Feng
- Science for Life Laboratory Uppsala, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Paulo C Alves
- CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, Vairão, Portugal.,Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, Porto, Portugal
| | | | - Nuno Ferrand
- CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, Vairão, Portugal.,Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, Porto, Portugal.,Department of Zoology, Faculty of Sciences, University of Johannesburg, Auckland, South Africa
| | - Leif Andersson
- Science for Life Laboratory Uppsala, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden.,Department of Animal Breeding and Genetics, Swedish University of Agricultural Sciences, Uppsala, Sweden.,Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, USA
| | - Miguel Carneiro
- CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, Vairão, Portugal.,Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, Porto, Portugal
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191
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Mason NA, Olvera‐Vital A, Lovette IJ, Navarro‐Sigüenza AG. Hidden endemism, deep polyphyly, and repeated dispersal across the Isthmus of Tehuantepec: Diversification of the White-collared Seedeater complex (Thraupidae: Sporophila torqueola). Ecol Evol 2018; 8:1867-1881. [PMID: 29435260 PMCID: PMC5792519 DOI: 10.1002/ece3.3799] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Revised: 12/04/2017] [Accepted: 12/11/2017] [Indexed: 12/21/2022] Open
Abstract
Phenotypic and genetic variation are present in all species, but lineages differ in how variation is partitioned among populations. Examining phenotypic clustering and genetic structure within a phylogeographic framework can clarify which biological processes have contributed to extant biodiversity in a given lineage. Here, we investigate genetic and phenotypic variation among populations and subspecies within a Neotropical songbird complex, the White-collared Seedeater (Sporophila torqueola) of Central America and Mexico. We combine measurements of morphology and plumage patterning with thousands of nuclear loci derived from ultraconserved elements (UCEs) and mitochondrial DNA to evaluate population differentiation. We find deep levels of molecular divergence between two S. torqueola lineages that are phenotypically diagnosable: One corresponds to S. t. torqueola along the Pacific coast of Mexico, and the other includes S. t. morelleti and S. t. sharpei from the Gulf Coast of Mexico and Central America. Surprisingly, these two lineages are strongly differentiated in both nuclear and mitochondrial markers, and each is more closely related to other Sporophila species than to one another. We infer low levels of gene flow between these two groups based on demographic models, suggesting multiple independent evolutionary lineages within S. torqueola have been obscured by coarse-scale similarity in plumage patterning. These findings improve our understanding of the biogeographic history of this lineage, which includes multiple dispersal events out of South America and across the Isthmus of Tehuantepec into Mesoamerica. Finally, the phenotypic and genetic distinctiveness of the range-restricted S. t. torqueola highlights the Pacific Coast of Mexico as an important region of endemism and conservation priority.
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Affiliation(s)
- Nicholas A. Mason
- Department of Ecology and Evolutionary BiologyCornell UniversityIthacaNYUSA
- Fuller Evolutionary Biology ProgramCornell Laboratory of OrnithologyIthacaNYUSA
| | | | - Irby J. Lovette
- Department of Ecology and Evolutionary BiologyCornell UniversityIthacaNYUSA
- Fuller Evolutionary Biology ProgramCornell Laboratory of OrnithologyIthacaNYUSA
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192
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Freudenstein JV, Broe MB, Folk RA, Sinn BT. Biodiversity and the Species Concept-Lineages are not Enough. Syst Biol 2018; 66:644-656. [PMID: 27798406 DOI: 10.1093/sysbio/syw098] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 10/14/2016] [Indexed: 11/13/2022] Open
Abstract
The nature and definition of species continue to be matters of debate. Current views of species often focus on their nature as lineages-maximal reproductive communities through time. Whereas many authors point to the Evolutionary Species Concept as optimal, in its original form it stressed the ecological role of species as well as their history as lineages, but most recent authors have ignored the role aspect of the concept, making it difficult to apply unambiguously in a time-extended way. This trend has been exacerbated by the application of methods and concepts emphasizing the notion of monophyly, originally applied only at higher levels, to the level of individuals, as well as by the current emphasis on molecular data. Hence, some current authors recognize units that are no more than probable exclusive lineages as species. We argue that biodiversity is inherently a phenotypic concept and that role, as manifested in the organismal extended phenotype, is a necessary component of the species concept. Viewing species as historically connected populations with unique role brings together the temporal and phenotypic natures of species, providing a clear way to view species both in a time-limited and time-extended way. Doing so alleviates perceived issues with "paraphyletic species" and returns the focus of species to units that are most relevant for biodiversity.
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Affiliation(s)
- John V Freudenstein
- Department of Evolution, Ecology and Organismal Biology, The Ohio State University Herbarium, 1315 Kinnear Road, Columbus, OH 43212, USA
| | - Michael B Broe
- Department of Evolution, Ecology and Organismal Biology, The Ohio State University Herbarium, 1315 Kinnear Road, Columbus, OH 43212, USA
| | - Ryan A Folk
- Department of Evolution, Ecology and Organismal Biology, The Ohio State University Herbarium, 1315 Kinnear Road, Columbus, OH 43212, USA.,Florida Museum of Natural History, University of Florida, 1659 Museum Road, Gainesville, FL 32611, USA
| | - Brandon T Sinn
- Department of Evolution, Ecology and Organismal Biology, The Ohio State University Herbarium, 1315 Kinnear Road, Columbus, OH 43212, USA.,New York Botanical Garden, 2900 Southern Blvd., Bronx, NY 10458, USA
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193
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Thom G, Amaral FRD, Hickerson MJ, Aleixo A, Araujo-Silva LE, Ribas CC, Choueri E, Miyaki CY. Phenotypic and Genetic Structure Support Gene Flow Generating Gene Tree Discordances in an Amazonian Floodplain Endemic Species. Syst Biol 2018; 67:700-718. [DOI: 10.1093/sysbio/syy004] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 01/23/2018] [Indexed: 01/25/2023] Open
Affiliation(s)
- Gregory Thom
- Departamento de Genética e Biologia Evolutiva, Universidade de São Paulo, Rua do Matão, 277, Cidade Universitária, São Paulo, SP 05508-090, Brazil
| | - Fabio Raposo Do Amaral
- Instituto de Ciências Ambientais, Químicas e Farmacêuticas, Laboratório de Genética Evolutiva, Universidade Federal de São Paulo, Rua Professor Artur Riedel, 275, Diadema, SP 09972–270, Brazil
| | - Michael J Hickerson
- Department of Biology, Marshak Science Building, City College of New York, 160, Convent Avenue, 10031 New York, NY, USA
| | - Alexandre Aleixo
- Departamento de Ornitologia, Museu Paraense Emílio Goeldi (MPEG), Caixa Postal 399, Belém, PA 66040-170, Brazil
| | - Lucas E Araujo-Silva
- Departamento de Ornitologia, Museu Paraense Emílio Goeldi (MPEG), Caixa Postal 399, Belém, PA 66040-170, Brazil
| | - Camila C Ribas
- Coordenação de biodiversidade, Instituto Nacional de Pesquisas da Amazônia (INPA), Av. André Araújo 2936, Manaus, AM 69060-001, Brazil
| | - Erik Choueri
- Coordenação de biodiversidade, Instituto Nacional de Pesquisas da Amazônia (INPA), Av. André Araújo 2936, Manaus, AM 69060-001, Brazil
| | - Cristina Y Miyaki
- Departamento de Genética e Biologia Evolutiva, Universidade de São Paulo, Rua do Matão, 277, Cidade Universitária, São Paulo, SP 05508-090, Brazil
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194
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Bay RA, Ruegg K. Genomic islands of divergence or opportunities for introgression? Proc Biol Sci 2018; 284:rspb.2016.2414. [PMID: 28275143 DOI: 10.1098/rspb.2016.2414] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 02/10/2017] [Indexed: 11/12/2022] Open
Abstract
In animals, introgression between species is often perceived as the breakdown of reproductive isolating mechanisms, but gene flow between incipient species can also represent a source for potentially beneficial alleles. Recently, genome-wide datasets have revealed clusters of differentiated loci ('genomic islands of divergence') that are thought to play a role in reproductive isolation and therefore have reduced gene flow. We use simulations to further examine the evolutionary forces that shape and maintain genomic islands of divergence between two subspecies of the migratory songbird, Swainson's thrush (Catharus ustulatus), which have come into secondary contact since the last glacial maximum. We find that, contrary to expectation, gene flow is high within islands and is highly asymmetric. In addition, patterns of nucleotide diversity at highly differentiated loci suggest selection was more frequent in a single ecotype. We propose a mechanism whereby beneficial alleles spread via selective sweeps following a post-glacial demographic expansion in one subspecies and move preferentially across the hybrid zone. We find no evidence that genomic islands are the result of divergent selection or reproductive isolation, rather our results suggest that differentiated loci both within and outside islands could provide opportunities for adaptive introgression across porous species boundaries.
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Affiliation(s)
- Rachael A Bay
- Center for Tropical Research, Institute for the Environment and Sustainability, University of California Los Angeles, Los Angeles, CA, USA
| | - Kristen Ruegg
- Center for Tropical Research, Institute for the Environment and Sustainability, University of California Los Angeles, Los Angeles, CA, USA
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195
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Frankl-Vilches C, Gahr M. Androgen and estrogen sensitivity of bird song: a comparative view on gene regulatory levels. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2018; 204:113-126. [PMID: 29209770 PMCID: PMC5790841 DOI: 10.1007/s00359-017-1236-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 11/02/2017] [Accepted: 11/09/2017] [Indexed: 12/16/2022]
Abstract
Singing of songbirds is sensitive to testosterone and its androgenic and estrogenic metabolites in a species-specific way. The hormonal effects on song pattern are likely mediated by androgen receptors (AR) and estrogen receptor alpha (ERα), ligand activated transcription factors that are expressed in neurons of various areas of the songbirds' vocal control circuit. The distribution of AR in this circuit is rather similar between species while that of ERα is species variant and concerns a key vocal control area, the HVC (proper name). We discuss the regulation of the expression of the cognate AR and ERα and putative splice variants. In particular, we suggest that transcription factor binding sites in the promoter of these receptors differ between bird species. Further, we suggest that AR- and ERα-dependent gene regulation in vocal areas differs between species due to species-specific DNA binding sites of putative target genes that are required for the transcriptional activity of the receptors. We suggest that species differences in the distribution of AR and ERα in vocal areas and in the genomic sensitivity to these receptors contribute to species-specific hormonal regulation of the song.
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Affiliation(s)
- Carolina Frankl-Vilches
- Department of Behavioural Neurobiology, Max Planck Institute for Ornithology, 82319, Seewiesen, Germany
| | - Manfred Gahr
- Department of Behavioural Neurobiology, Max Planck Institute for Ornithology, 82319, Seewiesen, Germany.
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196
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Luikart G, Kardos M, Hand BK, Rajora OP, Aitken SN, Hohenlohe PA. Population Genomics: Advancing Understanding of Nature. POPULATION GENOMICS 2018. [DOI: 10.1007/13836_2018_60] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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197
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198
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Nadeau NJ, Kawakami T. Population Genomics of Speciation and Admixture. POPULATION GENOMICS 2018. [DOI: 10.1007/13836_2018_24] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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199
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Low GW, Chattopadhyay B, Garg KM, Irestedt M, Ericson P, Yap G, Tang Q, Wu S, Rheindt FE. Urban landscape genomics identifies fine-scale gene flow patterns in an avian invasive. Heredity (Edinb) 2018; 120:138-153. [PMID: 29225353 PMCID: PMC5837122 DOI: 10.1038/s41437-017-0026-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 10/13/2017] [Accepted: 10/19/2017] [Indexed: 11/09/2022] Open
Abstract
Invasive species exert a serious impact on native fauna and flora and have been the target of many eradication and management efforts worldwide. However, a lack of data on population structure and history, exacerbated by the recency of many species introductions, limits the efficiency with which such species can be kept at bay. In this study we generated a novel genome of high assembly quality and genotyped 4735 genome-wide single nucleotide polymorphic (SNP) markers from 78 individuals of an invasive population of the Javan Myna Acridotheres javanicus across the island of Singapore. We inferred limited population subdivision at a micro-geographic level, a genetic patch size (~13-14 km) indicative of a pronounced dispersal ability, and barely an increase in effective population size since introduction despite an increase of four to five orders of magnitude in actual population size, suggesting that low population-genetic diversity following a bottleneck has not impeded establishment success. Landscape genomic analyses identified urban features, such as low-rise neighborhoods, that constitute pronounced barriers to gene flow. Based on our data, we consider an approach targeting the complete eradication of Javan Mynas across Singapore to be unfeasible. Instead, a mixed approach of localized mitigation measures taking into account urban geographic features and planning policy may be the most promising avenue to reducing the adverse impacts of this urban pest. Our study demonstrates how genomic methods can directly inform the management and control of invasive species, even in geographically limited datasets with high gene flow rates.
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Affiliation(s)
- G W Low
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore.
| | - B Chattopadhyay
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore
| | - K M Garg
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore
| | - M Irestedt
- Department of Bioinformatics and Genetics, Swedish Museum of Natural History, Frescativägen 54, Plan 3, Stockholm, 114018, Sweden
| | - Pgp Ericson
- Department of Zoology, Swedish Museum of Natural History, Frescativägen 54, Plan 3, Stockholm, 114018, Sweden
| | - G Yap
- Environmental Health Institute, National Environment Agency, 11 Biopolis Way, Singapore, 138667, Singapore
| | - Q Tang
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore
| | - S Wu
- Jiangsu Key Laboratory of Phylogenomics & Comparative Genomics, School of Life Sciences, Jiangsu Normal University, 101 Shanghai Road, Xuzhou, Jiangsu, 221116, China
| | - F E Rheindt
- Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore, 117543, Singapore.
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200
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Ancient polymorphisms and divergence hitchhiking contribute to genomic islands of divergence within a poplar species complex. Proc Natl Acad Sci U S A 2017; 115:E236-E243. [PMID: 29279400 PMCID: PMC5777044 DOI: 10.1073/pnas.1713288114] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
One of the outstanding questions in understanding how new species form is how reproductive isolation arises. In particular, the relative roles of gene flow and natural selection in creating two separate species remains open for debate. Here we show within the four continuously speciating lineages of a poplar that local genomic differentiation of populations is not associated with either rate of recent gene flow or time of species divergence. By contrast, we found that these genomic islands of divergence most likely came about by selective processes—sorting of ancient genetic polymorphisms and the incidental hitchhiking of linked variations. These findings substantially enhance our understanding of genomic changes in speciation. How genome divergence eventually leads to speciation is a topic of prime evolutionary interest. Genomic islands of elevated divergence are frequently reported between diverging lineages, and their size is expected to increase with time and gene flow under the speciation-with-gene-flow model. However, such islands can also result from divergent sorting of ancient polymorphisms, recent ecological selection regardless of gene flow, and/or recurrent background selection and selective sweeps in low-recombination regions. It is challenging to disentangle these nonexclusive alternatives, but here we attempt to do this in an analysis of what drove genomic divergence between four lineages comprising a species complex of desert poplar trees. Within this complex we found that two morphologically delimited species, Populus euphratica and Populus pruinosa, were paraphyletic while the four lineages exhibited contrasting levels of gene flow and divergence times, providing a good system for testing hypotheses on the origin of divergence islands. We show that the size and number of genomic islands that distinguish lineages are not associated with either rate of recent gene flow or time of divergence. Instead, they are most likely derived from divergent sorting of ancient polymorphisms and divergence hitchhiking. We found that highly diverged genes under lineage-specific selection and putatively involved in ecological and morphological divergence occur both within and outside these islands. Our results highlight the need to incorporate demography, absolute divergence measurement, and gene flow rate to explain the formation of genomic islands and to identify potential genomic regions involved in speciation.
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