The Evolution and Maintenance of the Color Polymorphism in Plethodon Cinereus
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
Pliocene Origin, Ice Ages and Postglacial Population Expansion Have Influenced a Panmictic Phylogeography of the European Bee-Eater Merops Apiaster
diversity Article Pliocene Origin, Ice Ages and Postglacial Population Expansion Have Influenced a Panmictic Phylogeography of the European Bee-Eater Merops apiaster Carina Carneiro de Melo Moura 1,*, Hans-Valentin Bastian 2 , Anita Bastian 2, Erjia Wang 1, Xiaojuan Wang 1 and Michael Wink 1,* 1 Department of Biology, Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, 69120 Heidelberg, Germany; [email protected] (E.W.); [email protected] (X.W.) 2 Bee-Eater Study Group of the DO-G, Geschwister-Scholl-Str. 15, 67304 Kerzenheim, Germany; [email protected] (H.V.B.); [email protected] (A.B.) * Correspondence: [email protected] (C.C.d.M.M.); [email protected] (M.W.) Received: 20 August 2018; Accepted: 26 December 2018; Published: 15 January 2019 Abstract: Oscillations of periods with low and high temperatures during the Quaternary in the northern hemisphere have influenced the genetic composition of birds of the Palearctic. During the last glaciation, ending about 12,000 years ago, a wide area of the northern Palearctic was under lasting ice and, consequently, breeding sites for most bird species were not available. At the same time, a high diversity of habitats was accessible in the subtropical and tropical zones providing breeding grounds and refugia for birds. As a result of long-term climatic oscillations, the migration systems of birds developed. When populations of birds concentrated in refugia during ice ages, genetic differentiation and gene flow between populations from distinct areas was favored. In the present study, we explored the current genetic status of populations of the migratory European bee-eater. -
De Novo Characterization of the Timema Cristinae Transcriptome Facilitates Marker Discovery and Inference of Genetic Divergence
Molecular Ecology Resources (2012) doi: 10.1111/j.1755-0998.2012.03121.x De novo characterization of the Timema cristinae transcriptome facilitates marker discovery and inference of genetic divergence AARON A. COMEAULT,* MATHEW SOMMERS,* TANJA SCHWANDER,† C. ALEX BUERKLE,‡ TIMOTHY E. FARKAS,* PATRIK NOSIL* and THOMAS L. PARCHMAN‡ *Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO 80303, USA, †Center for Ecology and Evolutionary Studies, University of Groningen, 9700CC Groningen, The Netherlands, ‡Department of Botany, University of Wyoming, Laramie, WY 82071, USA Abstract Adaptation to different ecological environments can promote speciation. Although numerous examples of such ‘ecological speciation’ now exist, the genomic basis of the process, and the role of gene flow in it, remains less understood. This is, at least in part, because systems that are well characterized in terms of their ecology often lack genomic resources. In this study, we characterize the transcriptome of Timema cristinae stick insects, a system that has been researched intensively in terms of ecological speciation, but for which genomic resources have not been previously developed. Specifically, we obtained >1 million 454 sequencing readsthatassembledinto84937contigsrepresenting approximately 18 282 unique genes and tens of thousands of potential molecular markers. Second, as an illustration of their utility, we used these geno- mic resources to assess multilocus genetic divergence within both an ecotype pair and a species pair of Timema stick insects. The results suggest variable levels of genetic divergence and gene flow among taxon pairs and genes and illustrate afirststeptowardsfuturegenomicworkinTimema. Keywords: gene flow, isolation with migration, next-generation sequencing, speciation, transcriptome Received 3 November 2011; revision received 6 January 2012; accepted 13 January 2012 Introduction resources (some notable exceptions aside, such as three- spine stickleback; Peichel et al. -
Frequency-Dependent Selection by Wild Birds Promotes Polymorphism in Model Salamanders
University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Faculty Publications and Other Works -- Ecology and Evolutionary Biology Ecology and Evolutionary Biology July 2013 Frequency-dependent selection by wild birds promotes polymorphism in model salamanders Benjamin M. Fitzpatrick University of Tennessee - Knoxville, [email protected] Kim Shook University of Tennessee - Knoxville Reuben Izally Farragut High School Follow this and additional works at: https://trace.tennessee.edu/utk_ecolpubs Part of the Ecology and Evolutionary Biology Commons Recommended Citation BMC Ecology 2009, 9:12 doi:10.1186/1472-6785-9-12 This Article is brought to you for free and open access by the Ecology and Evolutionary Biology at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Faculty Publications and Other Works -- Ecology and Evolutionary Biology by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. BMC Ecology BioMed Central Research article Open Access Frequency-dependent selection by wild birds promotes polymorphism in model salamanders Benjamin M Fitzpatrick*1, Kim Shook2,3 and Reuben Izally2,3 Address: 1Ecology & Evolutionary Biology, University of Tennessee, Knoxville TN 37996, USA, 2Pre-collegiate Research Scholars Program, University of Tennessee, Knoxville TN 37996, USA and 3Farragut High School, Knoxville TN 37934, USA Email: Benjamin M Fitzpatrick* - [email protected]; Kim Shook - [email protected]; Reuben Izally - [email protected] * Corresponding author Published: 8 May 2009 Received: 10 February 2009 Accepted: 8 May 2009 BMC Ecology 2009, 9:12 doi:10.1186/1472-6785-9-12 This article is available from: http://www.biomedcentral.com/1472-6785/9/12 © 2009 Fitzpatrick et al; licensee BioMed Central Ltd. -
Micro-Evolutionary Change and Population Dynamics of a Brood Parasite and Its Primary Host: the Intermittent Arms Race Hypothesis
Oecologia (1998) 117:381±390 Ó Springer-Verlag 1998 Manuel Soler á Juan J. Soler á Juan G. Martinez Toma sPe rez-Contreras á Anders P. Mùller Micro-evolutionary change and population dynamics of a brood parasite and its primary host: the intermittent arms race hypothesis Received: 7 May 1998 / Accepted: 24 August 1998 Abstract A long-term study of the interactions between Key words Brood parasitism á Clamator glandarius á a brood parasite, the great spotted cuckoo Clamator Coevolution á Parasite counter-defences á Pica pica glandarius, and its primary host the magpie Pica pica, demonstrated local changes in the distribution of both magpies and cuckoos and a rapid increase of rejection of Introduction both mimetic and non-mimetic model eggs by the host. In rich areas, magpies improved three of their defensive Avian brood parasites exploit hosts by laying eggs in mechanisms: nest density and breeding synchrony in- their nests, and parental care for parasitic ospring is creased dramatically and rejection rate of cuckoo eggs subsequently provided by the host. Parasitism has a increased more slowly. A stepwise multiple regression strongly adverse eect on the ®tness of hosts, given that analysis showed that parasitism rate decreased as host the young parasite ejects all host ospring or outcom- density increased and cuckoo density decreased. A lo- petes them during the nestling period (Payne 1977; gistic regression analysis indicated that the probability Rothstein 1990). Thus, there is strong selection acting on of changes in magpie nest density in the study plots was hosts to evolve defensive mechanisms against a brood signi®cantly aected by the density of magpie nests parasite which, in turn, will develop adaptive counter- during the previous year (positively) and the rejection defences. -
The Evolution of Müllerian Mimicry
CORE Metadata, citation and similar papers at core.ac.uk Provided by Springer - Publisher Connector Naturwissenschaften (2008) 95:681–695 DOI 10.1007/s00114-008-0403-y REVIEW The evolution of Müllerian mimicry Thomas N. Sherratt Received: 9 February 2008 /Revised: 26 April 2008 /Accepted: 29 April 2008 /Published online: 10 June 2008 # Springer-Verlag 2008 Abstract It is now 130 years since Fritz Müller proposed systems based on profitability rather than unprofitability an evolutionary explanation for the close similarity of co- and the co-evolution of defence. existing unpalatable prey species, a phenomenon now known as Müllerian mimicry. Müller’s hypothesis was that Keywords Müllerian mimicry. Anti-apostatic selection . unpalatable species evolve a similar appearance to reduce Warning signals . Predation the mortality involved in training predators to avoid them, and he backed up his arguments with a mathematical model in which predators attack a fixed number (n) of each Introduction distinct unpalatable type in a given season before avoiding them. Here, I review what has since been discovered about In footnote to a letter written in 1860 from Alfred Russel Müllerian mimicry and consider in particular its relation- Wallace to Charles Darwin, Wallace (1860)drewattentionto ship to other forms of mimicry. Müller’s specific model of a phenomenon that he simply could not understand: “P.S. associative learning involving a “fixed n” in a given season ‘Natural Selection’ explains almost everything in Nature, but has not been supported, and several experiments now there is one class of phenomena I cannot bring under it,—the suggest that two distinct unpalatable prey types may be repetition of the forms and colours of animals in distinct just as easy to learn to avoid as one. -
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. -
Panmixia of European Eel in the Sargasso Sea
Molecular Ecology (2011) doi: 10.1111/j.1365-294X.2011.05011.x FROM THE COVER All roads lead to home: panmixia of European eel in the Sargasso Sea THOMAS D. ALS,*1 MICHAEL M. HANSEN,‡1 GREGORY E. MAES,§ MARTIN CASTONGUAY,– LASSE RIEMANN,**2 KIM AARESTRUP,* PETER MUNK,†† HENRIK SPARHOLT,§§ REINHOLD HANEL–– and LOUIS BERNATCHEZ*** *National Institute of Aquatic Resources, Technical University of Denmark, Vejlsøvej 39, DK-8600 Silkeborg, Denmark, ‡Department of Biological Sciences, Aarhus University, Ny Munkegade 114, DK-8000 Aarhus C, Denmark, §Laboratory of Animal Diversity and Systematics, Katholieke Universiteit Leuven, B-3000, Leuven, Belgium, –Institut Maurice-Lamontagne, Fisheries and Oceans Canada, PO Box 1000 Mont-Joli, QC G5H 3Z4, Canada, **Department of Natural Sciences, Linnaeus University, SE-39182 Kalmar, Sweden, ††National Institute of Aquatic Resources, Technical University of Denmark, DK-2920 Charlottenlund, Denmark, §§International Council for Exploration of the Sea, DK-1553 Copenhagen, Denmark, ––Institute of Fisheries Ecology, Johann Heinrich von Thu¨nen-Institut (vTI), Federal Research Institute for Rural Areas, Forestry and Fisheries, Palmaille 9, 22767 Hamburg, Germany, ***De´partement de Biologie, Institut de Biologie Inte´grative et des Syste`mes (IBIS), Pavillon Charles-Euge`ne-Marchand, 1030, Avenue de la Me´decine, Universite´ Laval, QC G1V 0A6, Canada Abstract European eels (Anguilla anguilla) spawn in the remote Sargasso Sea in partial sympatry with American eels (Anguilla rostrata), and juveniles are transported more than 5000 km back to the European and North African coasts. The two species have been regarded as classic textbook examples of panmixia, each comprising a single, randomly mating population. However, several recent studies based on continental samples have found subtle, but significant, genetic differentiation, interpreted as geographical or temporal heterogeneity between samples. -
Phasmida (Stick and Leaf Insects)
● Phasmida (Stick and leaf insects) Class Insecta Order Phasmida Number of families 8 Photo: A leaf insect (Phyllium bioculatum) in Japan. (Photo by ©Ron Austing/Photo Researchers, Inc. Reproduced by permission.) Evolution and systematics Anareolatae. The Timematodea has only one family, the The oldest fossil specimens of Phasmida date to the Tri- Timematidae (1 genus, 21 species). These small stick insects assic period—as long ago as 225 million years. Relatively few are not typical phasmids, having the ability to jump, unlike fossil species have been found, and they include doubtful almost all other species in the order. It is questionable whether records. Occasionally a puzzle to entomologists, the Phasmida they are indeed phasmids, and phylogenetic research is not (whose name derives from a Greek word meaning “appari- conclusive. Studies relating to phylogeny are scarce and lim- tion”) comprise stick and leaf insects, generally accepted as ited in scope. The eggs of each phasmid are distinctive and orthopteroid insects. Other alternatives have been proposed, are important in classification of these insects. however. There are about 3,000 species of phasmids, although in this understudied order this number probably includes about 30% as yet unidentified synonyms (repeated descrip- Physical characteristics tions). Numerous species still await formal description. Stick insects range in length from Timema cristinae at 0.46 in (11.6 mm) to Phobaeticus kirbyi at 12.9 in (328 mm), or 21.5 Extant species usually are divided into eight families, in (546 mm) with legs outstretched. Numerous phasmid “gi- though some researchers cite just two, based on a reluctance ants” easily rank as the world’s longest insects. -
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). -
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. -
Ecological Character Displacement and the Study of Adaptation
Commentary Ecological character displacement and the study of adaptation Jonathan B. Losos* Department of Biology, Campus Box 1137, Washington University, St. Louis, MO 63130 he study of adaptation—a central is- Tsue in biology since before the time of Darwin—is currently enjoying a renais- sance. Ridiculed two decades ago as fol- lowing a panglossian paradigm (1) that Fig. 1. (Upper) Two sympatric promulgated ‘‘just so stories’’ rather than species with broadly overlapping distributions of resource use. If re- testing hypotheses, evolutionary biology sources are limiting, then natural has become a vibrant field in which a selection may favor individuals in wide variety of methods—ranging from each species with traits that allow molecular developmental biology to each of them to use that portion of manipulative field experiments—are used the resource spectrum not used by to rigorously test adaptive hypotheses (2). the other species, as indicated by Nowhere is this more evident than in the the arrows. (Lower) The result may study of ecological character displace- be that the species diverge in trait value and resource use, thus mini- ment; a paper by Adams and Rohlf (3) in mizing competition for resources. a recent issue of PNAS is one of a growing number of studies that have used integra- tive, multidisciplinary approaches and have demonstrated that ecological char- placement was seen as a powerful and enon for which few convincing examples acter displacement appears to be an pervasive force structuring ecological could be found (e.g., refs. 14–16). important ecological and evolutionary communities. These interpretations cor- These debates—unpleasant as they COMMENTARY phenomenon. -
Testing Local-Scale Panmixia Provides Insights Into the Cryptic Ecology, Evolution, and Epidemiology of Metazoan Animal Parasites
981 REVIEW ARTICLE Testing local-scale panmixia provides insights into the cryptic ecology, evolution, and epidemiology of metazoan animal parasites MARY J. GORTON†,EMILYL.KASL†, JILLIAN T. DETWILER† and CHARLES D. CRISCIONE* Department of Biology, Texas A&M University, 3258 TAMU, College Station, TX 77843, USA (Received 14 December 2011; revised 15 February 2012; accepted 16 February 2012; first published online 4 April 2012) SUMMARY When every individual has an equal chance of mating with other individuals, the population is classified as panmictic. Amongst metazoan parasites of animals, local-scale panmixia can be disrupted due to not only non-random mating, but also non-random transmission among individual hosts of a single host population or non-random transmission among sympatric host species. Population genetics theory and analyses can be used to test the null hypothesis of panmixia and thus, allow one to draw inferences about parasite population dynamics that are difficult to observe directly. We provide an outline that addresses 3 tiered questions when testing parasite panmixia on local scales: is there greater than 1 parasite population/ species, is there genetic subdivision amongst infrapopulations within a host population, and is there asexual reproduction or a non-random mating system? In this review, we highlight the evolutionary significance of non-panmixia on local scales and the genetic patterns that have been used to identify the different factors that may cause or explain deviations from panmixia on a local scale. We also discuss how tests of local-scale panmixia can provide a means to infer parasite population dynamics and epidemiology of medically relevant parasites.