DOCSLIB.ORG

Local Adaptation & Ecological Speciation

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Local Adaptation & Ecological Speciation Genomics of speciation and adaptation: Local adaptation & Ecological speciation 12.03.2019, Filip Kolář Where we are today? The gray zone of speciation Potential for gene flow is decreasing … reproductive isolation is accumulating Big question in this early phase What is the role of selection in speciation? Ecological triggers? Ecological speciation (link divergent selection & reproductive isolation) What makes the BDMI to arise – drift vs. selection? Sympatric speciation? (not today) Genomic architecture of early speciation Islands of divergence (not today) Adaptation A feature of an organism that has been favoured by natural selection because its positive effect on relative fitness Local adaptation Trait conferring higher fitness in specific environmental conditions (e.g. saline, serpentine soil, alpine env.) Adaptations are local – not found throughout species’ range Result of divergent selection Strict definition: Higher fitness at native site than any other introduced population Local adaptation Wild mice (Petromyscus) on differently coloured substrate Arabidopsis thaliana in Italy vs. Sweden Local adaptation Strict definition: Higher fitness at native site than any other introduced population Local Local Local Local Local Local Local Local Which of these show local adaptation (after L. Rieseberg) Ecotype A genetically distinct population/lineage adapted to specific local conditions Betula in Uppsala (Turesson 1930) Achillea in Sierra Nevada (Clausen, Keck Hiesey 1948) Side-note: Adaptive plasticity Plastic response on its own is adaptive (Not regarded here) Ranunculus subg. Batrachium – Terrestrial vs. aquatic form Why study local adaptation Evolutionary biology - quantifying selection strength “real-time” (ecological time) - may be incipient speciation - maintains genetic variation within a species Broader Impact - response to environmental change (immobile plants!!) - agriculture, forestry, human health Tree provenance trial Humans (Fan et al. 2016 Science) How study? Reciprocal transplant experiment Genetic differentiation for traits related to fitness - suggests local adaptation Arabidopsis thaliana in Sweden Peromyscus enclosures in Nebraska How study? Reciprocal transplant experiment How to measure fitness? Biomass? Recruitment / Survival N of progeny (and their fitness?) Among-year variation Agren Schemske 2012 New Phytol. Hereford 2008 How study? Environmental clines Clinal variation – altitudinal, latitudinal gradients Generality? 50 - 71% of cases – LA detected 45% average relative home-advantage Stronger LA Larger env. differences Larger populations Hereford 2008 (74 plant & animal studies), Leimu & Fischer (2008) (35 plant studies) Trade-off? Costs in the non-native environment? Hereford 2008 Genetic basis & genomic architecture Environmental association Common gardens studies NonsynSNPs (red) Syn. (green) LA-associated alleles – original sampling spots intergenic (yellow) associated with climate Hancock et al. 2011 Science, Fournier – Level et al. 2011 Science Genetic mapping (e.g., QTL): Cross both pops – subject F2 mapping population to both environments → “fitness loci” Genomic architecture? Generally largely unknown Differing fitness optima Few large-effect loci Many small-effect loci Lascoux et al. 2016 Genomic architecture? A. thaliana cross+RILs Few (15) fitness QTLs 1/3 of them trade-offs (local genotype favoured at each site) SW: freezing tolerance IT: flowering time Agren Schemske 2012 New Phytol. 15 Fitness QTLs (5 with trade-offs) in Arabidopsis thaliana, 398 RILs, 3 years, 40,000 plants (Agren et al. 2013 PNAS) Genetic basis? Genetic basis of fitness trade-offs: Genetic trade-off – allele beneficial at A, negative at B Conditional neutrality – allele beneficial at A, neutral elsewhere Two loci affecting the same fitness trait (Savolainen et al. 2013) Genomic architecture? Flowering time Conditional neutrality (beneficial in Italy, neutral in Sweden) Flowering time QTLS and overlap with fitness trade-off QTLs (arrow) (Agren et al. 2016 Evolution) Adaptation genes? Peromyscus: Local adaptation (evolution experiment) … at which site is selection stronger? Environment Survival Shift in Barrett et al. 2019 Science coloration Adaptation genes? … and the Agouti locus Allele freq. Change (recapture exp.) – significant in 549 SNPs ENCLOSURE WILD POP. Divergence scan – among SNPs associated with colour: single AA deletion significant selection signal (in both enclosure and natural pop) Mus transgenics … link: genotype-phenotype-fitness Wildtype Serine KO Barrett et al. 2019 Science Limits to adaptation No genetic variation Drift (can oppose selection) Fluctuating selection (in time) Gene flow (still LA possible, will prefer fewer loci with large effects) Savolainen et al. 2013 Adaptation or relaxed constraint? Is the alpine smaller because was selected for (freezing) or just mutation was tolerated (no competition)? Arabidopsis thaliana in ~4000 m a.s.l. Limits to adaptation - constraints Genetic correlations among traits (e.g. pleiotropy) (modified after L. Rieseberg) • Imagine a case where a single diallelic locus controls both inflorescence height and date of first flower Positive genetic Short inflorescence correlation t h 40 g i A e 35 h e 30 a c NS Early flowering n e 25 c s 20 Tall inflorescence e NS r o l 15 f n A a I 10 6 11 16 21 Late flowering Flowering date • Can natural selection lead to late flowering plants with short inflorescences? • Can natural selection lead to early flowering plants with tall inflorescences? Limits to adaptation - drift Small populations When migration – selection balance each other (Yeaman & Otto 2011, Lascoux et al. 2016) Ecological speciation When local adaptation turns into speciation… Wider definition: speciation triggered by divergent selection Three components: Ecological source of divergent selection Reproductive isolation Genetic component linking the two above Nosil 2012 Ecological speciation When local adaptation turns into speciation… Shared genetic mechanism Nosil 2012 Ecological speciation Timema cristinae stick insect in California Camouflage mechanisms – these loci resist introgression (accenuated differentiation between races) But does not affect mate-choice – instead assoc. with affected polygenic chemical signals (not growth of peaks of divergence) Timema bartmani Genetic diff. In Timema cristinae (Riesch et al. 2016 Nature Ecol Evol) Ecological speciation – key question How the gene flow is restricted? Allopatry Sexual selection Reinforcement “Magic traits” - one gene - pleiotropy on RI and target of divergent selection Ecological speciation – key question How the gene flow is restricted? “Magic traits” - one gene - pleiotropy on RI and target of divergent selection Wing colour patterns (mating pref. incl. paper models & divergent sel.) (Jiggins et al. 2001 Nature) Ecological speciation – key question What is the genetic basis? The same locus? Mimulus guttatus – copper mine adaptation Copper adaptation and hybrid lethality – two tightly linked loci → hitchhiking of the RI allele Segregating (C) and non-segregating (D) F2 indivs for copper tolerance (Copperopolis allele of Tol gene) (Wright et al. 2013 Plos Biology) Ecological speciation Ecological source of divergent selection Environmental differences Sexual selection Ecological interactions (e.g. plant-pollinator) Reproductive isolation Habitat and temporal isolation (flowering time) Immigrant inviability Sexual /pollinator isolation Postzygotic isolation (intrinsic, ecological, sexual) Genetic component linking the two above Direct selection & Pleiotropy Indirect selection & Linkage Gene flow Things might get more complex… Selection acting on constraints for speciation Melanistic form of Timema cristinae acts as a bridge in gene flow (Comeault et al. 2015 Curr.Biol.).
Load more

Recommended publications
  • Coupling, Reinforcement, and Speciation Roger Butlin, Carole Smadja
    Coupling, Reinforcement, and Speciation Roger Butlin, Carole Smadja To cite this version: Roger Butlin, Carole Smadja. Coupling, Reinforcement, and Speciation. American Naturalist, Uni- versity of Chicago Press, 2018, 191 (2), pp.155-172. 10.1086/695136. hal-01945350 HAL Id: hal-01945350 https://hal.archives-ouvertes.fr/hal-01945350 Submitted on 5 Dec 2018 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Distributed under a Creative Commons Attribution| 4.0 International License vol. 191, no. 2 the american naturalist february 2018 Synthesis Coupling, Reinforcement, and Speciation Roger K. Butlin1,2,* and Carole M. Smadja1,3 1. Stellenbosch Institute for Advanced Study, Wallenberg Research Centre at Stellenbosch University, Stellenbosch 7600, South Africa; 2. Department of Animal and Plant Sciences, The University of Sheffield, Sheffield S10 2TN, United Kingdom; and Department of Marine Sciences, University of Gothenburg, Tjärnö SE-45296 Strömstad, Sweden; 3. Institut des Sciences de l’Evolution, Unité Mixte de Recherche 5554 (Centre National de la Recherche Scientifique–Institut de Recherche pour le Développement–École pratique des hautes études), Université de Montpellier, 34095 Montpellier, France Submitted March 15, 2017; Accepted August 28, 2017; Electronically published December 15, 2017 abstract: During the process of speciation, populations may di- Introduction verge for traits and at their underlying loci that contribute barriers Understanding how reproductive isolation evolves is key fl to gene ow.
    [Show full text]
  • Ecological Speciation in Phytophagous Insects
    DOI: 10.1111/j.1570-7458.2009.00916.x MINI REVIEW Ecological speciation in phytophagous insects Kei W. Matsubayashi1, Issei Ohshima2 &PatrikNosil3,4* 1Department of Natural History Sciences, Hokkaido University, Sapporo 060-0810, Japan, 2Department of Evolutionary Biology, National Institute for Basic Biology, Okazaki 444-8585, Japan, 3Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO 80309, USA, and 4Wissenschaftskolleg, Institute for Advanced Study, Berlin, 14193, Germany Accepted: 7 August 2009 Key words: host adaptation, genetics of speciation, natural selection, reproductive isolation, herbivo- rous insects Abstract Divergent natural selection has been shown to promote speciation in a wide range of taxa. For exam- ple, adaptation to different ecological environments, via divergent selection, can result in the evolution of reproductive incompatibility between populations. Phytophagous insects have been at the forefront of these investigations of ‘ecological speciation’ and it is clear that adaptation to differ- ent host plants can promote insect speciation. However, much remains unknown. For example, there is abundant variability in the extent to which divergent selection promotes speciation, the sources of divergent selection, the types of reproductive barriers involved, and the genetic basis of divergent adaptation. We review these factors here. Several findings emerge, including the observation that although numerous different sources of divergent selection and reproductive isolation can be involved in insect speciation, their order of evolution and relative importance are poorly understood. Another finding is that the genetic basis of host preference and performance can involve loci of major effect and opposing dominance, factors which might facilitate speciation in the face of gene flow. In addition, we raise a number of other recent issues relating to phytophagous insect speciation, such as alternatives to ecological speciation, the geography of speciation, and the molecular signatures of spe- ciation.
    [Show full text]
  • Ecological Speciation with Gene Flow in Neodiprion Pinetum and N. Lecontei
    University of Kentucky UKnowledge Theses and Dissertations--Biology Biology 2020 FROM GENES TO SPECIES: ECOLOGICAL SPECIATION WITH GENE FLOW IN NEODIPRION PINETUM AND N. LECONTEI Emily E. Bendall University of Kentucky, [email protected] Author ORCID Identifier: https://orcid.org/0000-0003-2524-088X Digital Object Identifier: https://doi.org/10.13023/etd.2020.221 Right click to open a feedback form in a new tab to let us know how this document benefits ou.y Recommended Citation Bendall, Emily E., "FROM GENES TO SPECIES: ECOLOGICAL SPECIATION WITH GENE FLOW IN NEODIPRION PINETUM AND N. LECONTEI" (2020). Theses and Dissertations--Biology. 62. https://uknowledge.uky.edu/biology_etds/62 This Doctoral Dissertation is brought to you for free and open access by the Biology at UKnowledge. It has been accepted for inclusion in Theses and Dissertations--Biology by an authorized administrator of UKnowledge. For more information, please contact [email protected]. STUDENT AGREEMENT: I represent that my thesis or dissertation and abstract are my original work. Proper attribution has been given to all outside sources. I understand that I am solely responsible for obtaining any needed copyright permissions. I have obtained needed written permission statement(s) from the owner(s) of each third-party copyrighted matter to be included in my work, allowing electronic distribution (if such use is not permitted by the fair use doctrine) which will be submitted to UKnowledge as Additional File. I hereby grant to The University of Kentucky and its agents the irrevocable, non-exclusive, and royalty-free license to archive and make accessible my work in whole or in part in all forms of media, now or hereafter known.
    [Show full text]
  • Speciation in Parasites: a Population Genetics Approach
    Review TRENDS in Parasitology Vol.21 No.10 October 2005 Speciation in parasites: a population genetics approach Tine Huyse1, Robert Poulin2 and Andre´ The´ ron3 1Parasitic Worms Division, Department of Zoology, The Natural History Museum, Cromwell Road, London, UK, SW7 5BD 2Department of Zoology, University of Otago, PO Box 56, Dunedin, New Zealand 3Parasitologie Fonctionnelle et Evolutive, UMR 5555 CNRS-UP, CBETM, Universite´ de Perpignan, 52 Avenue Paul Alduy, 66860 Perpignan Cedex, France Parasite speciation and host–parasite coevolution dynamics and their influence on population genetics. The should be studied at both macroevolutionary and first step toward identifying the evolutionary processes microevolutionary levels. Studies on a macroevolutionary that promote parasite speciation is to compare existing scale provide an essential framework for understanding studies on parasite populations. Crucial, and novel, to this the origins of parasite lineages and the patterns of approach is consideration of the various processes that diversification. However, because coevolutionary inter- function on each parasite population level separately actions can be highly divergent across time and space, (from infrapopulation to metapopulation). Patterns of it is important to quantify and compare the phylogeo- genetic differentiation over small spatial scales provide graphic variation in both the host and the parasite information about the mode of parasite dispersal and their throughout their geographical range. Furthermore, to evolutionary dynamics. Parasite population parameters evaluate demographic parameters that are relevant to inform us about the evolutionary potential of parasites, population genetics structure, such as effective popu- which affects macroevolutionary events. For example, lation size and parasite transmission, parasite popu- small effective population size (Ne) and vertical trans- lations must be studied using neutral genetic markers.
    [Show full text]
  • Ecological Speciation
    International Journal of Ecology Ecological Speciation Guest Editors: Marianne Elias, Rui Faria, Zachariah Gompert, and Andrew Hendry Ecological Speciation International Journal of Ecology Ecological Speciation Guest Editors: Marianne Elias, Rui Faria, Zachariah Gompert, and Andrew Hendry Copyright © 2012 Hindawi Publishing Corporation. All rights reserved. This is a special issue published in “International Journal of Ecology.” All articles are open access articles distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Editorial Board Mariana Amato, Italy Jean-Guy Godin, Canada Panos V. Petrakis, Greece Madhur Anand, Canada David Goldstein, USA Daniel I. Rubenstein, USA Joseph R. Bidwell, USA Shibu Jose, USA Herman H. Shugart, USA L. M. Chu, Hong Kong Chandra Prakash Kala, India Andrew Sih, USA Jean Clobert, France Pavlos Kassomenos, Greece R.C. Sihag, India Michel Couderchet, France Thomas H. Kunz, USA C. ter Braak, The Netherlands Ronald D. Delaune, USA Bruce D. Leopold, USA John Whitaker, USA Andrew Denham, Australia A. E. Lugo, USA Walter Whitford, USA Mark A. Elgar, Australia Patricia Mosto, USA J. J. Wiens, USA Jingyun Fang, China Mats Olsson, Australia Xiaozhang Yu, China Contents Factors Influencing Progress toward Ecological Speciation, Marianne Elias, Rui Faria, Zachariah Gompert, and Andrew Hendry Volume 2012, Article ID 235010, 7 pages The Role of Parasitism in Adaptive RadiationsWhen Might Parasites Promote and When Might They Constrain Ecological Speciation?, Anssi Karvonen and Ole Seehausen Volume 2012, Article ID 280169, 20 pages Parallel Ecological Speciation in Plants?, Katherine L. Ostevik, Brook T. Moyers, Gregory L. Owens, and Loren H.
    [Show full text]
  • Adaptive Speciation
    Adaptive Speciation Edited by Ulf Dieckmann, Michael Doebeli, Johan A.J. Metz, and Diethard Tautz PUBLISHED BY THE PRESS SYNDICATE OF THE UNIVERSITY OF CAMBRIDGE The Pitt Building, Trumpington Street, Cambridge, United Kingdom CAMBRIDGE UNIVERSITY PRESS The Edinburgh Building, Cambridge CB2 2RU, UK 40 West 20th Street, New York, NY 10011-4211, USA 477 Williamstown Road, Port Melbourne, VIC 3207, Australia Ruiz de Alarcón 13, 28014 Madrid, Spain Dock House, The Waterfront, Cape Town 8001, South Africa http: //www.cambridge.org c International Institute for Applied Systems Analysis 2004 This book is in copyright. Subject to statutory exception and to the provisions of relevant collective licensing agreements, no reproduction of any part may take place without the written permission of the International Institute for Applied Systems Analysis. http://www.iiasa.ac.at First published 2004 Printed in the United Kingdom at the University Press, Cambridge Typefaces Times; Zapf Humanist 601 (Bitstream Inc.) System LATEX A catalog record for this book is available from the British Library ISBN 0 521 82842 2 hardback Contents Contributing Authors xi Acknowledgments xiii Notational Standards xiv 1 Introduction 1 Ulf Dieckmann, Johan A.J. Metz, Michael Doebeli, and Diethard Tautz 1.1 AShiftinFocus............................... 1 1.2 AdaptiveSpeciation............................. 2 1.3 AdaptiveSpeciationinContext....................... 6 1.4 SpeciesCriteria................................ 9 1.5 RoutesofAdaptiveSpeciation.......................
    [Show full text]
  • Is There a Microevolution to Macroevolution Barrier?
    diversity Article Life History Divergence in Livebearing Fishes in Response to Predation: Is There a Microevolution to Macroevolution Barrier? 1, 1, 1,2 Mark C. Belk * , Spencer J. Ingley y and Jerald B. Johnson 1 Department of Biology and Evolutionary Ecology Laboratories, Brigham Young University, Provo, UT 84602, USA; [email protected] (S.J.I.); [email protected] (J.B.J.) 2 Monte L. Bean Life Science Museum, Brigham Young University, Provo, UT 84602, USA * Correspondence: [email protected]; Tel.: +1-801-361-3243 Current address: Faculty of Science, Brigham Young University, Hawaii, Laie, HI 96762, USA. y Received: 10 April 2020; Accepted: 3 May 2020; Published: 5 May 2020 Abstract: A central problem in evolutionary biology is to determine whether adaptive phenotypic variation within species (microevolution) ultimately gives rise to new species (macroevolution). Predation environment can select for trait divergence among populations within species. The implied hypothesis is that the selection resulting from predation environment that creates population divergence within species would continue across the speciation boundary such that patterns of divergence after speciation would be a magnified accumulation of the trait variation observed before speciation. In this paper, we test for congruence in the mechanisms of microevolution and macroevolution by comparing the patterns of life history divergence among three closely related species of the livebearer genus Brachyrhaphis (Poeciliidae), namely B. rhabdophora, B. roseni, and B. terrabensis. Within B. rhabdophora, populations occur in either predator or predator-free environments, and have been considered to be at a nascent stage of speciation. Sister species B. roseni and B. terrabensis are segregated into predator and predator-free environments, respectively, and represent a post-speciation comparison.
    [Show full text]
  • Extraordinarily Rapid Speciation in a Marine Fish
    Extraordinarily rapid speciation in a marine fish Paolo Momiglianoa,1, Henri Jokinenb,2, Antoine Fraimoutc,2, Ann-Britt Florind, Alf Norkkob,e, and Juha Meriläa aEcological Genetics Research Unit, Department of Biosciences, University of Helsinki, FI-00014 Helsinki, Finland; bTvärminne Zoological Station, University of Helsinki, FI-10900 Hanko, Finland; cInstitut National de la Recherche Agronomique UMR, Centre de Biologie pour la Gestion des Populations (Institut National de la Recherche Agronomique/Institut de Recherche pour le Développement /Cirad/Montpellier SupAgro), FR-34988 Montferrier-sur-Lez, France; dDepartment of Aquatic Resources, Swedish University of Agricultural Sciences, SE-74242 Öregrund, Sweden; and eBaltic Sea Centre, Stockholm University, SE-10691 Stockholm, Sweden Edited by Dolph Schluter, University of British Columbia, Vancouver, BC, Canada, and accepted by Editorial Board Member Douglas Futuyma April 25, 2017 (received for review September 20, 2016) Divergent selection may initiate ecological speciation extremely enhances divergence at increasingly weakly selected loci, which in rapidly. How often and at what pace ecological speciation proceeds turn reduces gene flow (4). to yield strong reproductive isolation is more uncertain. Here, we In the marine environment, evidence for ecological speciation is document a case of extraordinarily rapid speciation associated with scarce (8). This is somehow surprising: barriers to gene flow are ecological selection in the postglacial Baltic Sea. European flounders rarely absolute in the sea, hence models of speciation that can (Platichthys flesus) in the Baltic exhibit two contrasting reproductive operate in the presence of gene flow, such as ecological speciation, behaviors: pelagic and demersal spawning. Demersal spawning en- are likely to be important in explaining marine biodiversity (8).
    [Show full text]
  • Testing Host-Plant Driven Speciation in Phytophagous Insects: a Phylogenetic Perspective
    Preprints (www.preprints.org) | NOT PEER-REVIEWED | Posted: 30 July 2019 doi:10.20944/preprints201902.0215.v2 1 Testing host-plant driven speciation in phytophagous insects: a phylogenetic perspective 2 3 Emmanuelle Jousselin* 1 , Marianne Elias 2 4 1. CBGP, INRA, CIRAD, IRD, Montpellier SupAgro, Univ Montpellier, Montpellier, France 5 2 Institut Systématique Evolution Biodiversité (ISYEB), Muséum national d'Histoire naturelle, 6 CNRS, Sorbonne Université, EPHE, Université des Antilles, 57 rue Cuvier, CP 50, 75005 Paris, 7 France. 8 *corresponding author: [email protected] 9 10 Keyword: coevolution, herbivory; host-plant specialization, phylogeny, speciation. 11 12 Abstract 13 During the last two decades, ecological speciation has been a major research theme in 14 evolutionary biology. Ecological speciation occurs when reproductive isolation between 15 populations evolves as a result of niche differentiation. Phytophagous insects represent model 16 systems for the study of this evolutionary process. The host-plants on which these insects feed and 17 often spend parts of their life cycle constitute ideal agents of divergent selection for these 18 organisms. Adaptation to feeding on different host-plant species can potentially lead to ecological 19 specialization of populations and subsequent speciation. This process is thought to have given 20 birth to the astonishing diversity of phytophagous insects and is often put forward in 21 macroevolutionary scenarios of insect diversification. Consequently, numerous phylogenetic 22 studies on phytophagous insects have aimed at testing whether speciation driven by host-plant 23 adaptation is the main pathway for the diversification of the groups under investigation. The 24 increasing availability of comprehensive and well-resolved phylogenies and the recent 25 developments in phylogenetic comparative methods are offering an unprecedented opportunity to 26 test hypotheses on insect diversification at a macroevolutionary scale, in a robust phylogenetic 27 framework.
    [Show full text]
  • Speciation Genomics 2020 W
    Workshop on Population and Speciation Genomics 2020 W. Salzburger | Speciation Speciation by Prof. Walter Salzburger Zoological Institute, University of Basel, Vesalgasse 1, 4051 Basel, Switzerland Speciation is the evolutionary process by which novel species originate from earlier ones. This process ———————— DIVERSIFICATION is, in principle, equivalent to the divergence of lineages — also called DIVERSIFICATION — at the level The accumulation of (genetic) differences of populations, but implies that new species have arisen from it. Speciation is responsible for the between two ore evolution of the organismal diversity of life on Earth. more taxa through time. Species concepts SPECIMEN An individual There is no consensus in biology what precisely a species is. In practical terms, individuals are grouped organism used for into species in order to categorize organisms and to give these categories names, which in turn scientific study or display. facilitates the identification of biological SPECIMENS. Species descriptions are usually done by taxonomists, who classify species on the basis of shared morphological characters following taxonomy GENE POOL guidelines. Such diagnostic characters are then used to distinguish between members of different species Total number of and to identify organisms, for example using field guides or identification keys. Species identification genes in an interbreeding can be cumbersome because of natural variation: Individuals within a species are variable and there is population at a given usually no “ideal” or “typical” individual. Evolutionary biologists, on the other hand, interpret species time (and across all individuals). as independent evolutionary units. Accordingly, members of the same species share a GENE POOL and fundamental evolutionary processes such as selection and DRIFT operate within a species.
    [Show full text]
  • Testing Host-Plant Driven Speciation in Phytophagous Insects
    RESEARCH ARTICLE Testing host-plant driven speciation in phytophagous insects : a phylogenetic perspective Emmanuelle Jousselin 1, Marianne Elias 2 1. CBGP, INRA, CIRAD, IRD, Montpellier SupAgro, Univ Montpellier, Montpellier, France 2 Cite as: Jousselin E, Elias M. Testing Institut Systématique Evolution Biodiversité (ISYEB), Muséum national d'Histoire host-plant driven speciation in naturelle, CNRS, Sorbonne Université, EPHE, Université des Antilles, 57 rue Cuvier, CP 50, phytophagous insects : a 75005 Paris, France. phylogenetic perspective. ArXiv: 1910.09510, Peer-reviewed and recommended by PCI Evolutionary Biology, (2019). This article has been peer-reviewed and recommended by Peer Community in Evolutionary Biology Posted: 20 th October 2019 Recommender: ABSTRACT Hervé Sauquet During the last two decades, ecological speciation has been a major research theme in evolutionary biology. Ecological speciation occurs when reproductive Reviewers: isolation between populations evolves as a result of niche differentiation. Brian O’Meara and one anonymous Phytophagous insects represent model systems for the study of this evolutionary reviewer process. The host-plants on which these insects feed and often spend parts of Correspondence: their life cycle constitute ideal agents of divergent selection for these organisms. [email protected] Adaptation to feeding on different host-plant species can potentially lead to ecological specialization of populations and subsequent speciation. This process is thought to have given birth to the astonishing diversity of phytophagous insects and is often put forward in macroevolutionary scenarios of insect diversification. Consequently, numerous phylogenetic studies on phytophagous insects have aimed at testing whether speciation driven by host-plant adaptation is the main pathway for the diversification of the groups under investigation.
    [Show full text]
  • Mechanisms of Assortative Mating in Speciation
    Mechanisms of Assortative Mating in Speciation with Gene Flow: Connecting Theory and Empirical Research Michael Kopp, Maria Servedio, Tamra Mendelson, Rebecca Safran, Rafael Rodríguez, Mark Hauber, Elizabeth Scordato, Laurel Symes, Christopher Balakrishnan, David Zonana, et al. To cite this version: Michael Kopp, Maria Servedio, Tamra Mendelson, Rebecca Safran, Rafael Rodríguez, et al.. Mech- anisms of Assortative Mating in Speciation with Gene Flow: Connecting Theory and Empirical Re- search. American Naturalist, University of Chicago Press, 2018, 191 (1), pp.1-20. 10.1086/694889. hal-02013886 HAL Id: hal-02013886 https://hal.archives-ouvertes.fr/hal-02013886 Submitted on 2 May 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. vol. 191, no. 1 the american naturalist january 2018 Synthesis Mechanisms of Assortative Mating in Speciation with Gene Flow: Connecting Theory and Empirical Research Michael Kopp,1,*,† Maria R. Servedio,2,* Tamra C. Mendelson,3 Rebecca J. Safran,4 Rafael L. Rodríguez,5 Mark E. Hauber,6 Elizabeth C. Scordato,4 Laurel B. Symes,7 Christopher N. Balakrishnan,8 David M. Zonana,4 and G. Sander van Doorn9 1. Aix Marseille Université, CNRS, Centrale Marseille, I2M, 3 Place Victor Hugo, 13331 Marseille Cedex 3, France; 2.
    [Show full text]