Population Genetics of Polymorphism and Divergence in Rapidly Evolving Populations

Total Page:16

File Type:pdf, Size:1020Kb

Population Genetics of Polymorphism and Divergence in Rapidly Evolving Populations bioRxiv preprint doi: https://doi.org/10.1101/2021.06.28.450258; this version posted June 30, 2021. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC 4.0 International license. Population genetics of polymorphism and divergence in rapidly evolving populations Matthew J. Melissa1, Benjamin H. Good2, Daniel S. Fisher2, and Michael M. Desai1∗ 1Department of Organismic and Evolutionary Biology, Department of Physics, Quantitative Biology Initiative, and NSF-Simons Center for Mathematical and Statistical Analysis of Biology, Harvard University 2Department of Applied Physics and Department of Bioengineering, Stanford University ∗[email protected] (Dated: June 29, 2021) In rapidly evolving populations, numerous beneficial and deleterious mutations can arise and segregate within a population at the same time. In this regime, evolutionary dy- namics cannot be analyzed using traditional population genetic approaches that assume that sites evolve independently. Instead, the dynamics of many loci must be analyzed simultaneously. Recent work has made progress by first analyzing the fitness variation within a population, and then studying how individual lineages interact with this travel- ing fitness wave. However, these \traveling wave" models have previously been restricted to extreme cases where selection on individual mutations is either much faster or much slower than the typical coalescent timescale Tc. In this work, we show how the traveling wave framework can be extended to intermediate regimes in which the scaled fitness effects of mutations (Tcs) are neither large nor small compared to one. This enables us to describe the dynamics of populations subject to a wide range of fitness effects, and in particular, in cases where it is not immediately clear which mutations are most important in shaping the dynamics and statistics of genetic diversity. We use this ap- proach to derive new expressions for the fixation probabilities and site frequency spectra of mutations as a function of their scaled fitness effects, along with related results for the coalescent timescale Tc and the rate of adaptation or Muller's ratchet. We find that competition between linked mutations can have a dramatic impact on the proportions of neutral and selected polymorphisms, which is not simply summarized by the scaled selection coefficient Tcs. We conclude by discussing the implications of these results for population genetic inferences. I. INTRODUCTION with fitness effect s will fix. From this quantity, we can compute the rate at which mutations will accu- Models of evolutionary dynamics and population mulate (i.e. the rate of genotypic divergence from an genetics aim to predict how observable properties ancestor) and the rate, v, at which the mean fitness of the distribution of genotypes within a population of the population changes over time (McCandlish are shaped by evolutionary forces such as mutations, and Stoltzfus, 2014). In addition to these properties natural selection, and genetic drift. We focus here on of long-term divergence, we wish to predict expected the simplest possible models of these three core evo- patterns of genetic diversity within the population lutionary forces, which consider a population con- at any given time. For example, we aim to compute sisting of N individuals, with each individual sub- the coalescence timescale Tc (the typical time since ject to new mutations at rate U per generation, and individuals are related by common ancestry, which with the fitness effect of each mutation drawn from determines the expected overall level of genetic di- some distribution ρ(s). More complicated models of versity in the population), as well as other readily evolutionary dynamics can incorporate the effects of observable quantities such as the site frequency spec- additional evolutionary forces (e.g., spatial structure trum (which describes the relative abundances of and migration, environmental fluctuations in time polymorphisms at different allele frequencies). Ob- or space, and ecological interactions). However, the taining predictions for patterns of genetic diversity dynamics arising from even the simplest models| is of particular interest because of the potential to incorporating only the forces of mutation, selection, use these predictions, in combination with measured genetic drift|are already rather complex. levels of contemporary sequence diversity, to infer the strength of the various evolutionary forces which Within the context of these simple models, we have acted on a population. wish to understand how several types of observables depend on the key parameters. Specifically, we aim Much classical work proceeds by assuming the dif- to predict the probability, pfix(s), that a mutation ferent loci in the genome evolve completely indepen- bioRxiv preprint doi: https://doi.org/10.1101/2021.06.28.450258; this version posted June 30, 2021. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC 4.0 International license. 2 dently of one another (i.e., by ignoring the physical vian coalescent (McVean and Cardin, 2005)), and linkage of mutations within the same genomic seg- can also incorporate other complications such as ge- ment). The dynamics are then relatively straightfor- ographic subdivision, population structure, and de- ward to analyze (Fisher, 1931; Wright, 1931). This mographic changes (Nordborg, 2004). However, the assumption is reasonable in sexually evolving pop- backwards-time nature of the coalescent approach ulations where recombination is sufficiently rapid makes it difficult to incorporate the effects of se- compared to the timescales on which mutation, se- lection: genealogies cannot be considered indepen- lection and genetic drift generate correlations be- dently of the selected mutations which occur on their tween loci (Falconer and Mackay, 1996). In this case, branches (Kaplan et al., 1988). Efforts to do so have a given mutation is shuffled onto a large number of largely been limited to simulation-based or essen- genetic backgrounds over the course of its evolution- tially numerical approaches, such as the ancestral se- ary trajectory, and any correlations in the fates of lection graph (Krone and Neuhauser, 1997), though mutations at different loci become negligible. analytical progress has been made in certain cases, In asexual populations, however, mutations are particularly in the presence of purifying selection on are fully linked and do not evolve independently of deleterious mutations (Charlesworth, 1994; Hudson one another. Even in the genomes of obligately sex- and Kaplan, 1995). ual organisms, loci that are physically close within To model the effects of selection on beneficial mu- a chromosome will be broken up by recombination tations, much work has instead been done using only over very long timescales, and cannot necessar- forward-time approaches. Broadly speaking, these ily be treated as independently evolving (Weissman approaches seek to characterize the trajectories of and Barton, 2012). A useful opposite regime to con- mutant lineages in a probabilistic sense. Provided sider is then the limit of a genomic region that is selection is sufficiently strong and selected mutations small enough that recombination can be entirely ne- are sufficiently rare (more precisely, if Ns 1 and glected. One can imagine that on sufficiently short NU log Ns < 1), a beneficial mutation typically ei- genomic distance scales (within so-called \linkage ther sweeps to fixation or is purged before another blocks"), evolution proceeds entirely asexually, while such mutation arises within the same linkage block on larger genomic distance scales evolution acts on (Desai and Fisher, 2007). Thus, within this strong- some collection of recombining blocks. It is not en- selection weak-mutation (SSWM) regime, multiple tirely clear how this division between asexual linkage selected mutations are unlikely to segregate simulta- blocks and larger-scale regions consisting of multiple neously within the block. In this case, the dynamics recombining blocks is best modeled, though some re- of each selected mutation can be treated indepen- cent work has begun to address this question (Good dently of one another, using the single-locus meth- et al., 2014; Neher et al., 2013; Weissman and Hal- ods described above (Gillespie, 1983). The impact latschek, 2014). However, we focus in this paper on of these mutations on linked neutral diversity can an even simpler question: how to model the evolu- also be calculated from these dynamics (e.g., to an- tion within a single nonrecombining linkage block. alyze the signature of an isolated selective sweep) As we will see, even within the context of the simple (Smith and Haigh, 1974). However, recent work models described above, evolutionary dynamics even has shown that in a wide range of microbial and within perfectly asexual linkage blocks are surpris- viral populations, and potentially in many linked re- ingly complex, and remain incompletely understood. gions of the genomes of obligately sexual organisms There is a long history of efforts to analyze the such as humans, multiple beneficial mutations often dynamics of purely asexual evolution, and numer- segregate simultaneously (Lieberman et al., 2014; ous approaches
Recommended publications
  • ENZYME POLYMORPHISM and ADAPTATION ( Enzyme Polymorphism, Electrophor Esis, Neutral Hypothesis)
    STADLER SYMP. Vo l . 7 ( 1 975) University of Missouri, Columbia - 91 ENZYME POLYMORPHISM AND ADAPTATION ( enzyme polymorphism, electrophor esis, neutral hypothesis) GEORGE B. JOHNSON Depa rtment of Biology Washin gt on University St. Louis, Missouri 631 30 SUMMARY After a brief resume of the controversy concerning the adaptive value of enzyme polymorphisms , a physiological hypo­ thesis is advanced that heterosis for enzymes of intermediary metabolism results from the differential kinetic behavior of the alleles, which in heterozygotes serve to buffer rate - deter­ mining reactions from environmental perturbations . Polymor­ phism within a population of alpine butterflies is examined in some detail , and the results strongly implicate ongoing selec­ tive processes. A more detailed understanding would seem to require more pointed in vivo physiological analyses of the polymorphic variants. A characterization of the physical na­ ture of the electrophoretic variants suggests that many vari ­ ants do not involve a charge difference , while almost all in­ volve a significant conformational difference. The value of explicit error estimates associated with each data characteri ­ zation is stressed throughout. INTRODUCTION With the extensive use in the last ten years of zone elec­ trophoresis as a genetic survey technique, it has become clear that level s of genet ic variability are quite h i gh in natural populations. The average levels of heterozygosity exceed 10% , 30% of examined loci are polymorphic . Thi s degree of varia­ bility is much higher than had been expected, and its inter­ pretation has become one of the central questions of popula­ tion genetics. Kimura and others have advanced the idea that this level of genetic variation reflects random events , the polymorphic enzyme alleles detected by electrophoresis actually having 92 JOHNSON little or no differential effect on fitness.
    [Show full text]
  • Polymorphism Under Apostatic
    Heredity (1984), 53(3), 677—686 1984. The Genetical Society of Great Britain POLYMORPHISMUNDER APOSTATIC AND APOSEMATIC SELECTION VINTON THOMPSON Department of Biology, Roosevelt University, 430 South Michigan Avenue, Chicago, Illinois 60805 USA Received31 .i.84 SUMMARY Selection for warning colouration in well-defended species should lead to a single colour form in each local population, but some species are locally polymor- phic for aposematic colour forms. Single-locus two-allele models of frequency- dependent selection indicate that combined apostatic and aposematic selection may maintain stable polymorphism for one, two or three aposematic forms, provided that at least one form is subject to net apostatic selection. Frequency- independent selective differences between colour forms broaden the possibilities for aposematic polymorphism but lead to monomorphism if too large. Concurrent apostatic and aposematic selection may explain polymorphism for warning colouration in a number of jumping or moderately unpalatable insects. 1. INTRODUCTION Polymorphism for warning colouration poses a paradox for evolutionists because, as Fisher (1958) seems to have been the first to note, selection for warning colouration (aposematic selection) should lead to monomorphism. Under aposematic selection predators tend to avoid previously encountered phenotypes of undesirable prey, so that the fitness of each phenotype increases as it becomes more common. Given the presence of two forms, each will suffer at the hands of predators conditioned to avoid the other and one will eventually prevail because as soon as it gets the upper hand numerically it will drive the other to extinction. Nonetheless, many species are polymorphic for colour forms that appear to be aposematic. The ladybird beetles (Coccinellidae) furnish a number of particularly striking examples (Hodek, 1973; and see illustration in Ayala, 1978).
    [Show full text]
  • I Xio- and Made the Rather Curious Assumption That the Mutant Is
    NOTES AND COMMENTS NATURAL SELECTION AND THE EVOLUTION OF DOMINANCE P. M. SHEPPARD Deportment of Genetics, University of Liverpool and E.B. FORD Genetic Laboratories, Department of Zoology, Oxford 1. INTRODUCTION CROSBY(i 963) criticises the hypothesis that dominance (or recessiveness) has evolved and is not an attribute of the allelomorph when it arose for the first time by mutation. None of his criticisms is new and all have been discussed many times. However, because of a number of apparent mis- understandings both in previous discussions and in Crosby's paper, and the fact that he does not refer to some important arguments opposed to his own view, it seems necessary to reiterate some of the previous discussion. Crosby's criticisms fall into two parts. Firstly, he maintains, as did Wright (1929a, b) and Haldane (1930), that the selective advantage of genes modifying dominance, being of the same order of magnitude as the mutation rate, is too small to have any evolutionary effect. Secondly, he criticises, as did Wright (5934), the basic assumption that a new mutation when it first arises produces a phenotype somewhat intermediate between those of the two homozygotes. 2.THE SELECTION COEFFICIENT INVOLVED IN THE EVOLUTION OF DOMINANCE Thereis no doubt that the selective advantage of modifiers of dominance is of the order of magnitude of the mutation rate of the gene being modified. Crosby (p. 38) considered a hypothetical example with a mutation rate of i xio-and made the rather curious assumption that the mutant is dominant in the absence of modifiers of dominance.
    [Show full text]
  • Ecological and Evolutionary Dynamics of Interconnectedness and Modularity
    Ecological and evolutionary dynamics of interconnectedness and modularity Jan M. Nordbottena,b, Simon A. Levinc, Eörs Szathmáryd,e,f, and Nils C. Stensethg,1 aDepartment of Mathematics, University of Bergen, N-5020 Bergen, Norway; bDepartment of Civil and Environmental Engineering, Princeton University, Princeton, NJ 08544; cDepartment of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544; dParmenides Center for the Conceptual Foundations of Science, D-82049 Pullach, Germany; eMTA-ELTE (Hungarian Academy of Sciences—Eötvös University), Theoretical Biology and Evolutionary Ecology Research Group, Department of Plant Systematics, Ecology and Theoretical Biology, Eötvös University, Budapest, H-1117 Hungary; fEvolutionary Systems Research Group, MTA (Hungarian Academy of Sciences) Ecological Research Centre, Tihany, H-8237 Hungary; and gCentre for Ecological and Evolutionary Synthesis (CEES), Department of Biosciences, University of Oslo, N-0316 Oslo, Norway Contributed by Nils C. Stenseth, December 1, 2017 (sent for review September 12, 2017; reviewed by David C. Krakauer and Günter P. Wagner) In this contribution, we develop a theoretical framework for linking refinement of this inquiry is to look for compartmentalization (i.e., microprocesses (i.e., population dynamics and evolution through modularity) in ecosystems. In food webs, for example, compartments natural selection) with macrophenomena (such as interconnectedness (which are subgroups of taxa with many strong interactions in each and modularity within an
    [Show full text]
  • What Genomic Data Can Reveal About Eco-Evolutionary Dynamics
    PERSPECTIVE https://doi.org/10.1038/s41559-017-0385-2 What genomic data can reveal about eco-evolutionary dynamics Seth M. Rudman 1*, Matthew A. Barbour2, Katalin Csilléry3, Phillip Gienapp4, Frederic Guillaume2, Nelson G. Hairston Jr5, Andrew P. Hendry6, Jesse R. Lasky7, Marina Rafajlović8,9, Katja Räsänen10, Paul S. Schmidt1, Ole Seehausen 11,12, Nina O. Therkildsen13, Martin M. Turcotte3,14 and Jonathan M. Levine15 Recognition that evolution operates on the same timescale as ecological processes has motivated growing interest in eco-evo- lutionary dynamics. Nonetheless, generating sufficient data to test predictions about eco-evolutionary dynamics has proved challenging, particularly in natural contexts. Here we argue that genomic data can be integrated into the study of eco-evo- lutionary dynamics in ways that deepen our understanding of the interplay between ecology and evolution. Specifically, we outline five major questions in the study of eco-evolutionary dynamics for which genomic data may provide answers. Although genomic data alone will not be sufficient to resolve these challenges, integrating genomic data can provide a more mechanistic understanding of the causes of phenotypic change, help elucidate the mechanisms driving eco-evolutionary dynamics, and lead to more accurate evolutionary predictions of eco-evolutionary dynamics in nature. vidence that the ways in which organisms interact with their evolution plays a central role in regulating such dynamics. environment can evolve fast enough to alter ecological dynam- Particularly relevant is information gleaned from efforts to under- Eics has forged a new link between ecology and evolution1–5. A stand the genomic basis of adaptation, a burgeoning field in evolu- growing area of study, termed eco-evolutionary dynamics, centres tionary biology that investigates the specific genomic underpinnings on understanding when rapid evolutionary change is a meaningful of phenotypic variation, its response to natural selection and effects driver of ecological dynamics in natural ecosystems6–8.
    [Show full text]
  • Martin A. Nowak
    EVOLUTIONARY DYNAMICS EXPLORING THE EQUATIONS OF LIFE MARTIN A. NOWAK THE BELKNAP PRESS OF HARVARD UNIVERSITY PRESS CAMBRIDGE, MASSACHUSETTS, AND LONDON, ENGLAND 2006 Copyright © 2006 by the President and Fellows of Harvard College All rights reserved Printed in Canada Library of Congress Cataloging-in-Publication Data Nowak, M. A. (Martin A.) Evolutionary dynamics : exploring the equations of life / Martin A. Nowak. p. cm. Includes bibliographical references and index. ISBN-13: 978-0-674-02338-3 (alk. paper) ISBN-10: 0-674-02338-2 (alk. paper) 1. Evolution (Biology)—Mathematical models. I. Title. QH371.3.M37N69 2006 576.8015118—dc22 2006042693 Designed by Gwen Nefsky Frankfeldt CONTENTS Preface ix 1 Introduction 1 2 What Evolution Is 9 3 Fitness Landscapes and Sequence Spaces 27 4 Evolutionary Games 45 5 Prisoners of the Dilemma 71 6 Finite Populations 93 7 Games in Finite Populations 107 8 Evolutionary Graph Theory 123 9 Spatial Games 145 10 HIV Infection 167 11 Evolution of Virulence 189 12 Evolutionary Dynamics of Cancer 209 13 Language Evolution 249 14 Conclusion 287 Further Reading 295 References 311 Index 349 PREFACE Evolutionary Dynamics presents those mathematical principles according to which life has evolved and continues to evolve. Since the 1950s biology, and with it the study of evolution, has grown enormously, driven by the quest to understand the world we live in and the stuff we are made of. Evolution is the one theory that transcends all of biology. Any observation of a living system must ultimately be interpreted in the context of its evolution. Because of the tremendous advances over the last half century, evolution has become a dis- cipline that is based on precise mathematical foundations.
    [Show full text]
  • Evolutionary Dynamics on Any Population Structure
    Evolutionary dynamics on any population structure Benjamin Allen1,2,3, Gabor Lippner4, Yu-Ting Chen5, Babak Fotouhi1,6, Naghmeh Momeni1,7, Shing-Tung Yau3,8, and Martin A. Nowak1,8,9 1Program for Evolutionary Dynamics, Harvard University, Cambridge, MA, USA 2Department of Mathematics, Emmanuel College, Boston, MA, USA 3Center for Mathematical Sciences and Applications, Harvard University, Cambridge, MA, USA 4Department of Mathematics, Northeastern University, Boston, MA, USA 5Department of Mathematics, University of Tennessee, Knoxville, TN, USA 6Institute for Quantitative Social Sciences, Harvard University, Cambridge, MA, USA 7Department of Electrical and Computer Engineering, McGill University, Montreal, Canada 8Department of Mathematics, Harvard University, Cambridge, MA, USA 9Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA December 23, 2016 Abstract Evolution occurs in populations of reproducing individuals. The structure of a biological population affects which traits evolve [1, 2]. Understanding evolutionary game dynamics in structured populations is difficult. Precise results have been absent for a long time, but have recently emerged for special structures where all individuals have the arXiv:1605.06530v2 [q-bio.PE] 22 Dec 2016 same number of neighbors [3, 4, 5, 6, 7]. But the problem of deter- mining which trait is favored by selection in the natural case where the number of neighbors can vary, has remained open. For arbitrary selection intensity, the problem is in a computational complexity class which suggests there is no efficient algorithm [8]. Whether there exists a simple solution for weak selection was unanswered. Here we provide, surprisingly, a general formula for weak selection that applies to any graph or social network.
    [Show full text]
  • Gene Mutation and DNA Polymorphism Outline of This Chapter
    Gene mutation and DNA polymorphism Outline of this chapter Gene Mutation DNA Polymorphism GeneGene MutationMutation Definition Major Types DefinitionDefinition A gene mutation is a change in the nucleotide sequence that composes a gene. Somatic mutations Germline mutations SomaticSomatic mutationsmutations are mutations that occur in cells of the body excluding the germline. Affects subsequent somatic cell descendants Limited to impact on the individual and not transmitted to offspring Germline mutations are mutations that occur in the germline cells Possibility of transmission to offspring Major Types Point mutations Insertion or deletion Fusion gene Dynamic mutation Point mutation substitution of one base with another Point mutation Transition purine replaces purine A G or pyrimidine replaces pyrimidine C T Transversion purine replaces pyrimidine A G or pyrimidine replaces purine C T What are the consequences? Within coding region: Silent mutation (same sense mutation) Missense mutation Nonsense mutation Stop codon mutation Within noncoding region: Splicing mutation Regulatory sequence mutation SilentSilent MutationMutation changes one codon for an amino acid to another codon for that amino acid no change in amino acid MissenseMissense mutationmutation A point mutation that exchanges one codon for another causing substitution of an amino acid Missense mutations may affect protein function severely, mildly or not at all. CGT AGT Hemoglobin Four globular proteins surrounding heme group with iron atom: two beta chains and two alpha chains Function is to carry oxygen in red blood cells from lungs to body and carbon dioxide from cells to lungs SingleSingle basebase changechange inin hemoglobinhemoglobin genegene causescauses sicklesickle cellcell anemiaanemia Wild-type mutant allele allele Wild-type mutant phenotype phenotype NonsenseNonsense mutationmutation A point mutation changing a codon for an amino acid into a stop codon (UAA, UAG or UGA).
    [Show full text]
  • Population Genetics of Polymorphism and Divergence Stanley A
    Population Genetics of Polymorphism and Divergence Stanley A. Sawyer∗, † and Daniel L. Hartl† ∗Department of Mathematics, Washington University, St. Louis, Missouri 63130, †Department of Genetics, Washington University School of Medicine, St. Louis, Missouri 63110 November 3, 1992 ABSTRACT Frequencies of mutant sites are modeled as a Poisson random field in two species that share a sufficiently recent common ancestor. The selective effect of the new alleles can be favorable, neutral, or detrimental. The model is applied to the sample configurations of nucleotides in the alcohol dehydrogenase gene (Adh) in Drosophila simulans and D. yakuba (McDonald and Kreitman 1991, Nature 351: 652–654). Assuming a synonymous mutation rate of 1.5 × 10−8 per site per year and 10 generations per year, we obtain 6 estimates for the effective population size (Ne =6.5 × 10 ), the species divergence time −6 (tdiv =3.74 Myr), and an average selection coefficient (σ =1.53 × 10 per generation for advantageous or mildly detrimental replacements), although it is conceivable that only two of the amino acid replacements were selected and the rest neutral. The analysis, which includes a sampling theory for the independent infinite sites model with selection, also suggests the estimate that the number of amino acids in the enzyme that are susceptible to favorable mutation is in the range 2–23 out of 257 total possible codon positions at any one time. The approach provides a theoretical basis for the use of a 2 × 2 contingency table to compare fixed differences and polymorphic sites with silent sites and amino acid replacements. t has been more than 25 years since Lewontin have been more at odds, and a great controversy en- I and Hubby (1966) first demonstrated high levels sued.
    [Show full text]
  • Speciation Genetics: Evolving Approaches
    REVIEWS Speciation genetics: evolving approaches Mohamed A. F. Noor* and Jeffrey L. Feder‡ Abstract | Much progress has been made in the past two decades in understanding Darwin’s mystery of the origins of species. Applying genomic techniques to the analysis of laboratory crosses and natural populations has helped to determine the genetic basis of barriers to gene flow which create new species. Although new methodologies have not changed the prevailing hypotheses about how species form, they have accelerated the pace of data collection. By facilitating the compilation of case studies, advances in genetic techniques will help to provide answers to the next generation of questions concerning the relative frequency and importance of different processes that cause speciation. Gene flow What types of genetic change bring about speciation is sophisticated methods has led to finer dissection of the The movement of alleles one of the most basic questions in biology. Speciation is a genetic origins of species down to the level of the indi- between local populations that fundamental outcome of life. Given metabolism, repro- vidual loci and eventually nucleotides. Technical and is due to the migration of duction, mutation, heredity, and the spatial–temporal statistical advances are also extending laboratory-based individuals. subdivision of the environment and of individuals into discovery to natural populations, allowing researchers Hybrid zone populations, new species form through time, increasing to investigate barriers to gene flow, genomic interactions A location where the hybrid biodiversity. The evolution of this biodiversity can only and the genetic permeability of species boundaries in offspring of two divergent, be fully explained if we identify the heritable underpin- hybrid zones where differentiated taxa overlap and inter- partially geographically nings of species formation and the forces responsible breed.
    [Show full text]
  • Evolutionary Game Theory: a Renaissance
    games Review Evolutionary Game Theory: A Renaissance Jonathan Newton ID Institute of Economic Research, Kyoto University, Kyoto 606-8501, Japan; [email protected] Received: 23 April 2018; Accepted: 15 May 2018; Published: 24 May 2018 Abstract: Economic agents are not always rational or farsighted and can make decisions according to simple behavioral rules that vary according to situation and can be studied using the tools of evolutionary game theory. Furthermore, such behavioral rules are themselves subject to evolutionary forces. Paying particular attention to the work of young researchers, this essay surveys the progress made over the last decade towards understanding these phenomena, and discusses open research topics of importance to economics and the broader social sciences. Keywords: evolution; game theory; dynamics; agency; assortativity; culture; distributed systems JEL Classification: C73 Table of contents 1 Introduction p. 2 Shadow of Nash Equilibrium Renaissance Structure of the Survey · · 2 Agency—Who Makes Decisions? p. 3 Methodology Implications Evolution of Collective Agency Links between Individual & · · · Collective Agency 3 Assortativity—With Whom Does Interaction Occur? p. 10 Assortativity & Preferences Evolution of Assortativity Generalized Matching Conditional · · · Dissociation Network Formation · 4 Evolution of Behavior p. 17 Traits Conventions—Culture in Society Culture in Individuals Culture in Individuals · · · & Society 5 Economic Applications p. 29 Macroeconomics, Market Selection & Finance Industrial Organization · 6 The Evolutionary Nash Program p. 30 Recontracting & Nash Demand Games TU Matching NTU Matching Bargaining Solutions & · · · Coordination Games 7 Behavioral Dynamics p. 36 Reinforcement Learning Imitation Best Experienced Payoff Dynamics Best & Better Response · · · Continuous Strategy Sets Completely Uncoupled · · 8 General Methodology p. 44 Perturbed Dynamics Further Stability Results Further Convergence Results Distributed · · · control Software and Simulations · 9 Empirics p.
    [Show full text]
  • Evolutionary Dynamics on Graphs
    letters to nature Received 24 September; accepted 16 November 2004; doi:10.1038/nature03211. often individuals place offspring into adjacent vertices. The 3 1. MacArthur, R. H. & Wilson, E. O. The Theory of Island Biogeography (Princeton Univ. Press, homogeneous population, described by the Moran process ,is Princeton, 1969). the special case of a fully connected graph with evenly weighted 2. Fisher, R. A., Corbet, A. S. & Williams, C. B. The relation between the number of species and the number of individuals in a random sample of an animal population. J. Anim. Ecol. 12, 42–58 (1943). edges. Spatial structures are described by graphs where vertices 3. Preston, F. W. The commonness, and rarity, of species. Ecology 41, 611–627 (1948). are connected with their nearest neighbours. We also explore 4. Brown, J. H. Macroecology (Univ. Chicago Press, Chicago, 1995). evolution on random and scale-free networks5–7. We determine 5. Hubbell, S. P. A unified theory of biogeography and relative species abundance and its application to the fixation probability of mutants, and characterize those tropical rain forests and coral reefs. Coral Reefs 16, S9–S21 (1997). 6. Hubbell, S. P. The Unified Theory of Biodiversity and Biogeography (Princeton Univ. Press, Princeton, graphs for which fixation behaviour is identical to that of a 7 2001). homogeneous population . Furthermore, some graphs act as 7. Caswell, H. Community structure: a neutral model analysis. Ecol. Monogr. 46, 327–354 (1976). suppressors and others as amplifiers of selection. It is even 8. Bell, G. Neutral macroecology. Science 293, 2413–2418 (2001). possible to find graphs that guarantee the fixation of any 9.
    [Show full text]