DOCSLIB.ORG

The Classes of Endosymbiont of Paramecium Aurelia

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
The Classes of Endosymbiont of Paramecium Aurelia J. Cell Sci. 5, 65-91 (1969) 65 Printed in Great Britain THE CLASSES OF ENDOSYMBIONT OF PARAMECIUM AURELIA G. H. BEALE AND A. JURAND Institute of Animal Genetics, Edinburgh 9, Scotland AND J. R. PREER Department of Zoology, Indiana University, Bloomington, Indiana 47401, U.S.A. SUMMARY The endosymbionts of Paramecium aurelia appear to consist of a number of different Gram- negative bacteria which have come to live within many strains of paramecia. It is not known whether in nature this relationship is mutually beneficial or not. The symbionts from one paramecium may kill other paramecia lacking that kind of symbiont. We identify the following classes of endosymbiotic organisms. First, kappa particles (found in P. aurelia, syngens 2 and 4) ordinarily contain highly characteristic refractile, or R, bodies, which are associated with the production of a toxin which kills sensitive paramecia. In certain mutants of kappa found in the laboratory both R bodies and ability to kill have been lost. Second, mu particles (in syngens i, 2 and 8) produce the phenomenon of mate-killing. Third, lambda (syngens 4 and 8) and sigma particles (syngen 2) are very large, flagellated organisms which kill only paramecia of syngens 3, 5 and 9, and are enclosed in membrane-bound vacuoles. Fourth, gamma particles (syngen 8) are minute endosymbionts, surrounded by an additional membrane resembling endoplasmic reticulum. They have strong killing activity but no R bodies. Fifth, delta particles (syngens 1 and 6) possess a dense layer covering the outer membrane. At least one of the two known stocks is a killer. Sixth, nu particles are a heterogeneous group of particles (syngens 2 and 5) which do not kill or possess distinctive morphological characteristics. Seventh, alpha particles (syngen 2) are the only known nuclear symbionts of P. aurelia; they are found in the macronucleus. Alpha is also exceptional in being the only particle which is highly infectious, though certain of the other symbionts can also be taken up by paramecia lacking them, under special conditions. INTRODUCTION The object of this paper is to survey the different kinds of endosymbiont which grow in the cytoplasm or macronucleus of Paramecium aurelia. In using the word 'endosymbiont', we simply mean one organism living within the cells of another, and do not imply anything about the interactions between host and symbiont, whether beneficial or harmful. Knowledge of the symbionts of P. aurelia stems from the dis- covery by Sonneborn (1938a), that certain strains of the ciliate are 'killers'. The killer paramecia were originally inferred to contain kappa particles in the cytoplasm from the inheritance of the killer trait (Sonneborn, 1945). It was shown that, due to the presence of kappa, a toxic material, at first called 'paramecin', was released into the water, and sensitive paramecia in the vicinity were damaged or killed. Later, kappa particles were identified under the light microscope by examination of fixed and stained paramecia (Preer, 1950) and by observations with the phase-contrast microscope of unstained crushed paramecia (Preer & Stark, 1953). 5 Cell Sci. 5 66 G. H. Beak, A. Jurand and J. R. Freer Killer paramecia and kappa particles were at first considered to be of interest as illustrations of non-Mendelian heredity. However, in the course of time attention has been concentrated more on the nature of the particles themselves. By 1959 such details of the structure and composition of kappa (and related) particles as were then known, showed that they were as large and complex as bacteria, though kappa particles had some peculiar features not previously known in typical bacteria (Sonneborn, 1959). After the initial discovery of the first killer paramecia, other types were found. Siegel (1953) described the 'mate-killers', and Schneller (1958) described the 'rapid- lysis' killers. These different types of killer paramecia were each found to contain distinct cytoplasmic particles, those in mate-killers being called 'mu', and those in rapid-lysis killers 'lambda'. Moreover, a number of variants (or 'mutants') of the original kappa particles were found (Dippell, 1950). One variant discovered by Hanson (1954) was denoted 'pi'. These pi particles were distinguished from the original kappas by the loss of killing properties associated with the particles. By 1956 it had become clear that kappa and similar particles were by no means uncommon constitutents of paramecia. Sonneborn (1956) estimated that at least 30% of stocks of certain syngens of P. aurelia when first collected from nature were killers or mate-killers. It has been known for many years that if paramecia are washed in bacteria-free medium, crushed and observed in the phase-contrast microscope the presence of endosymbionts may be ascertained, irrespective of whether there is any killing effect or not (Preer & Stark, 1953). More recently a simple and much more rapid technique has been devised whereby one can quickly see whether kappa or other particles are present in a paramecium (Beale & Jurand, 1966). It is now known that a substantial proportion of wild strains of paramecia contain symbionts in the cytoplasm, and some even in the macronucleus. So many types have now come to light that we feel it is desirable to attempt a comparative survey and an assessment of the homologies and significance of the symbionts. It should be stressed that this paper is in no sense a complete account of our know- ledge of any of the particles. Fuller information about some of them (kappa, mu, lambda) is given in an earlier review by Sonneborn (1959). MATERIALS AND METHODS Techniques used in these studies will be found in the following papers: (1) details of the methods used in collecting and cultivating paramecia are given by Sonneborn (1950); (2) the demonstration of killing (including mate-killing phenomena) is described by Sonneborn (1959); (3) for recognition of endosymbionts by light micro- scopy of stained whole paramecia see Beale & Jurand (1966) and by phase-contrast microscopy of crushed paramecia see Preer & Stark (1953); (4) for techniques for electron microscopy see Jurand & Preer (1968). The material used in the various studies referred to in this paper belongs to a number of the syngens of P. aurelia. (The term syngen was introduced by Sonneborn (1957) to refer to a group of stocks between which conjugation may occur and result in Endosymbionts of Paramecium 67 viable progeny.) Table 1 contains a list of the stocks referred to in this paper, a stock being the progeny of a single individual collected from nature. Although in this account we refer to symbiont-bearing stocks in the syngens in which they are known (syngens 1, 2, 4, 5, 6 and 8), not all the known symbiont-bearing stocks in these syngens appear in the table, and some other symbionts occur in syngens not yet described. Stocks which bear numbers in the series 1-350 were kindly supplied by Dr T. M. Sonneborn; those with numbers above 500 are from our own collections. Table 1. Syngens, stocks and symbionts referred to in this paper Syngen Stock no. Place collected Type of symbiont 54° Mexico Mu 548 Los Angeles, California, U.S.A. Mu 55i San Francisco, California, U.S.A. Mu 555 Monterey, California, U.S.A. Mu 561 Pisa, Italy Delta 2 7 N. Carolina, U.S.A. Kappa 562 Milan, Italy Kappa and alpha 57O Georgia, U.S.S.R. Mu 114 Bloomington, Indiana, U.S.A. Sigma IOIO Cove Lake, Tennessee, U.S.A. Nu Hu 35-1 Edinburgh, Scotland Nu 4 51 Spencer, Indiana, U.S.A. Kappa 239 Holmes Co., Florida, U.S.A. Lambda 5 87 Philadelphia, U.S.A. Nu 314 Pike Co., Illinois, U.S.A. Nu 6 225 Florida, U.S.A. Delta 8 216 Florida, U.S.A. Lambda 229 Florida, U.S.A. Lambda 299 Panama Lambda 214 Florida, U.S.A. Gamma 565 Uganda Gamma THE CLASSES OF SYMBIONTS Introduction In this survey we shall continue to use the system of denoting the principal types of symbionts by Greek letters. The widely varying amounts of morphological data available for each symbiont, and especially the paucity of biochemical data, make it impossible for us to adopt a binomial system at present. Symbionts which seem to form a group are given the same Greek letter. In addition, each sample of a symbiont is characterized by the stock number of its host paramecium (e.g. 51-kappa, 540-mu etc.), irrespective of whether two or more examples of a given type of symbiont, occurring in different stocks, appear to be alike. Kappa Kappa is the original symbiont in P. aurelia discovered and named by Sonneborn (1945). The most characteristic feature of kappa particles now appears to be their 5-2 68 G. H. Beak, A. Jurand and jf. R. Freer content, at some stage in their development, of the peculiar structures called 'R' (refractile) bodies (Figs, i, 2). There is usually one R body per kappa particle, but occasionally two or even more may be seen (Preer & Stark, 1953). Killing activity of kappa particles is associated with the presence of these R bodies (Preer, Siegel & Stark, 1953; Smith, 1961; Mueller, 1963; Preer & Preer, 1964). It is assumed that kappa particles are released from paramecia into the medium, and if sensitive organisms take up kappa particles which contain R bodies, killing may result. Definition of kappa particles on the basis of their possession of R bodies is, however, somewhat unsatisfactory. First, such particles (which were denoted 'brights' by Preer & Stark, 1953) are never found alone in the cytoplasm of a paramecium. They are always accompanied by a population of 'non-bright' kappa particles, the number of which usually exceeds that of the 'brights'.
Load more

Recommended publications
  • CSHL AR 1981.Pdf
    ANNUAL REPORT 1981 COLD SPRING HARBOR LABORATORY Cold Spring Harbor Laboratory Box 100, Cold Spring Harbor, New York 11724 1981 Annual Report Editors: Annette Kirk, Elizabeth Ritcey Photo credits: 9, 12, Elizabeth Watson; 209, Korab, Ltd.; 238, Robert Belas; 248, Ed Tronolone. All otherphotos by Herb Parsons. Front and back covers: Sammis Hall, new residence facility at the Banbury Conference Center.Photos by K orab, Ltd. COLD SPRING HARBOR LABORATORY COLD SPRING HARBOR, LONG ISLAND, NEW YORK OFFICERS OF THE CORPORATION Walter H. Page, Chairman Dr. Bayard Clarkson, Vice-Chairman Dr. Norton D. Zinder, Secretary Robert L. Cummings, Treasurer Roderick H. Cushman, Assistant Treasurer Dr. James D. Watson, Director William R. Udry, Administrative Director BOARD OF TRUSTEES Institutional Trustees Individual Trustees Albert Einstein College of Medicine John F. Carr Dr. Matthew Scharff Emilio G. Collado Robert L. Cummings Columbia University Roderick H. Cushman Dr. Charles Cantor Walter N. Frank, Jr. John P. Humes Duke Mary Lindsay Dr. Robert Webster Walter H. Page William S. Robertson Long Island Biological Association Mrs. Franz Schneider Edward Pulling Alexander C. Tomlinson Dr. James D. Watson Massachusetts Institute of Technology Dr. Boris Magasanik Honorary Trustees Memorial Sloan-Kettering Cancer Center Dr. Bayard Clarkson Dr. Harry Eagle Dr. H. Bentley Glass New York University Medical Center Dr. Alexander Hollaender Dr. Claudio Basilico The Rockefeller University Dr. Norton D. Zinder State University of New York, Stony Brook Dr. Thomas E. Shenk University of Wisconsin Dr. Masayasu Nomura Wawepex Society Bache Bleeker Yale University Dr. Charles F. Stevens Officers and trustees are as of December 31, 1981 DIRECTOR'S REPORT 1981 The daily lives of scientists are much less filled now be solvable or whether we must await the re- with clever new ideas than the public must im- ception of some new facts that as yet do not exist.
    [Show full text]
  • Data on the Occurrence of Species of the Paramecium Aurelia Complex World-Wide
    Protistology 1 (4), 179–184 (2000) Protistology August, 2000 Data on the occurrence of species of the Paramecium aurelia complex world-wide Ewa Przybo and Sergei Fokin1 Institute of Systematics and Evolution of Animals, Polish Academy of Sciences, Kraków, Poland, 1 Biological Research Institute of St. Petersburg State University, St. Petersburg, Russia Summary At present 15 species of the Paramecium aurelia complex are known world-wide (Sonneborn, 1975; Aufderheide et al., 1983). Data on their distribution in the Americas, Africa, and Australia are mainly in the papers cited above, the following ones are cosmopolitan: P. primaurelia, P. biaurelia, P. tetraurelia, and P. sexaurelia. Data on the distribution of species of the P. aurelia complex in Asia are scattered in the literature and rather rare, P. primaurelia, P. biaurelia, P. tetraurelia, P. sexaurelia, and P. novaurelia were there recorded. The greatest data on distribution and frequency of occurrence of the particular species of the P. aurelia complex concerns Europe. As far as Europe is concerned, the following conclusions were drawn: P. novaurelia is a dominant species (found in 178 habitats among 459 studied), P. biaurelia is a frequent one (in 151 habitats), while P. primaurelia (in 103 habitats) is also characteristic but less frequent. Other species known from Europe are rare. Key words: frequency of species occurrence, geographical distribution, Paramecium aurelia spp. complex At present 15 species of the P. aurelia complex are occurrence of the particular species of the P. aurelia com- known world-wide (Sonneborn,1975; Aufderheide et al., plex concerns Europe (Table 3). The following species 1983). have been recorded there: P.
    [Show full text]
  • Factors Determining the Frequency of the Killer Trait Within Populations of the Paramecium Aurelia Complex
    Copyright 0 1987 by the Genetics Society of America Factors Determining the Frequency of the Killer Trait Within Populations of the Paramecium aurelia Complex Wayne G. Landis Environmental Toxicology Branch, Toxicology Division, Chemical Research and Development Center, Aberdeen Proving Ground, Maryland, 21010-5423 Manuscript received March 3, 1986 Revised copy accepted September 15, 1986 ABSTRACT The factors maintaining the cytoplasmically inherited killer trait in populations of Paramecium tetraurelia and Paramecium biaurelia were examined using, in part, computer simulation. Frequency of the K and k alleles, infection and loss of the endosymbionts,recombination during conjugation and autogamy, cytoplasmic exchange and natural selection were incorporated in a model. Infection during cytoplasmic exchange at conjugation and natural selection were factors that would increase the proportion of killers in a population. Conversely, k alleles reduced the proportion of killers in a population,acting through conjugation and autogamy. Field studies indicate that the odd mating type is prevalent in P. tetraurelia isolated from nature. Conjugation and therefore transmission by cyto- plasmic transfer would be rare. Competition studies indicate a strong selective disadvantage for sensitives at concentrationsfound in nature. Natural selection must therefore be the factor maintaining the killer trait in P. tetraurelia. YTOPLASMIC inheritance is a widespread phe- The two hosts, P. tetraurelia and P. biaurelia, are C nomenon that includes sex and drug resistance sibling species within the P. aurelia complex as con- in bacteria, CO2 sensitivity in Drosophilia melanogaster structed by SONNEBORN(1975). Paramecia of this and possibly certain tumors in mammals. Indeed, the complex undergo two major sexual processes, conju- origin of the eukaryotic cell may have been dependent gation and autogamy.
    [Show full text]
  • The Culture of Paramecium a Ureliain the Absence
    VOL. 35, 1949 ZOOLOGY: VAN WAGTENDONK AND HACKETT 155 6 See, for example, top of page 9, J. of Symbolic Logic, 6. 7Compare middle of page 158, Ibid., 7. 8 Am. Math. Mo., 44, p. 70. 9 J. of Symbolic Logic, 7, p. 1. The inconisistent system contains N7' in place of N7. However, whether the replacement of N7' by N7 would affect the derivation of the Burali-Forti contradiction is not immediately obvious. 10 Middle of page 228, J. r. angew. Math., 160. 11 If we want to obtain N7' instead of N7, just delete the clause "and all the bound variables in 4 are small variables" in ZZ7. 1 Compare the proof of *231, ML, page 171. 13 Ti can be proved by ZZI and ZZ1 in the usual manner. Cf., e.g., ML, page 170, *223. * I am indebted to Dr. I. L. Novak for suggestion in connection with the introduction of large variables. I wish also to thank Dr. Novak and Dr. H. Hiz for reading the manuscript of the paper and suggesting improvements in the manner of presentation. I am grateful to Professor Quine for corrections. THE CULTURE OF PARAMECIUM A URELIA IN THE ABSENCE OF OTHER LIVING ORGANISMS BY W. J. VAN WAGTENDONK AND PATRICIA L. HACKETT DEPARTMENT OF ZOOLOGY, INDIANA UNIVERSITY, BLOOMINGTON, INDIANA Communicated by T. M. Sonneborn, January 22, 1949 The growth requirements of ciliated protozoa are very complex, and little accurate work on this has so far been possible since only a few species have been cultivated in the absence of other living organisms.
    [Show full text]
  • Paramecium Diversity and a New Member of the Paramecium Aurelia Species Complex Described from Mexico
    diversity Article Paramecium Diversity and a New Member of the Paramecium aurelia Species Complex Described from Mexico Alexey Potekhin 1,2,* and Rosaura Mayén-Estrada 3 1 Department of Microbiology, Faculty of Biology, Saint Petersburg State University, 199034 Saint Petersburg, Russia 2 Laboratory of Cellular and Molecular Protistology, Zoological Institute RAS, 199034 Saint Petersburg, Russia 3 Laboratorio de Protozoología, Facultad de Ciencias, Universidad Nacional Autónoma de México, Circuito Ext. s/núm. Ciudad Universitaria, Av. Universidad 3000, Coyoacán, 04510 Ciudad de México, Mexico; [email protected] * Correspondence: [email protected] http://zoobank.org/urn:lsid:zoobank.org:act:B5A24294-3165-40DA-A425-3AD2D47EB8E7 Received: 17 April 2020; Accepted: 13 May 2020; Published: 15 May 2020 Abstract: Paramecium (Ciliophora) is an ideal model organism to study the biogeography of protists. However, many regions of the world, such as Central America, are still neglected in understanding Paramecium diversity. We combined morphological and molecular approaches to identify paramecia isolated from more than 130 samples collected from different waterbodies in several states of Mexico. We found representatives of six Paramecium morphospecies, including the rare species Paramecium jenningsi, and Paramecium putrinum, which is the first report of this species in tropical regions. We also retrieved five species of the Paramecium aurelia complex, and describe one new member of the complex, Paramecium quindecaurelia n. sp., which appears to be a sister species of Paramecium biaurelia. We discuss criteria currently applied for differentiating between sibling species in Paramecium. Additionally, we detected diverse bacterial symbionts in some of the collected ciliates. Keywords: biogeography; ciliates; Paramecium quindecaurelia; cytochrome C oxidase subunit I gene; sibling species; species concept in protists; bacterial symbionts 1.
    [Show full text]
  • Virtual Lab-Population Biology-Information Questions & Data
    VIRTUAL LAB: POPULATION BIOLOGY How does competition affect population growth? Interspecific competition between two species of Paramecium Background Information The genus Paramecium consists of unicellular species of protists that live in freshwater environments. Under ideal conditions – sufficient food, water, and space – populations of these species grow rapidly and follow a pattern known as exponential growth. Exponential growth is an explosive population growth in which the total number of potentially reproducing organisms increase with each generation. However, population of organisms will not increase in size forever. Eventually, limitations on food, water, and other resources will cause the population to stop increasing. When a population arrives at the point where its size remains stable, it has reached the carrying capacity of the environment. The carrying capacity is the greatest number of individuals a given environment can sustain. Competition for resources among members of a population (intraspecific competition) places limits on population size. Competition for resources among members of two or more different species (interspecific competition) also affects population size. In a classic series of experiments in the 1930s, a Russian ecologist, G.F. Gause, formulated his principal of competitive exclusion. This principle states that if two species are competing for the same resource, the species with a more rapid growth rate will outcompete the other. In other words, no two species can occupy the same niche. In competing populations of organisms, genetic variations that reduce competition are favored through natural selection. Suppose two species (A and B) compete for the same food source. Individuals of species A can also use another food source, which reduces the competition over the food source needed by species B.
    [Show full text]
  • Description and Molecular Phylogeny of Paramecium Grohmannae Sp. Nov
    ISSN 1517-6770 Description and molecular phylogeny of Paramecium grohmannae sp. nov. (Ciliophora, Peniculida) from a wastewater treatment plant in Brazil Thiago da Silva Paiva1,2,*, Bárbara do Nascimento Borges3, Maria Lúcia Harada2 & Inácio Domingos da Silva-Neto4 1Laboratory of Evolutionary Protistology, Instituto de Biociências, Universidade de São Paulo. 2Laboratório de Biologia Molecular “Francisco Mauro Salzano”, Instituto de Ciências Biológicas, Universidade Federal do Pará 3Centro de Tecnologia Agropecuária, Instituto Socioambiental e dos Recursos Hídricos, Universidade Federal Rural da Amazônia 4Laboratório de Protistologia, Departamento de Zoologia, Instituto de Biologia, CCS, Universidade Federal do Rio de Janeiro *Corresponding author:[email protected] Abstract. A new morphological species of Paramecium Müller, 1773, was discovered in samples of water with activated sludge of a wastewater treatment plant in Rio de Janeiro, Brazil. It is described based on light microscopy and its phylogenetic position hypothesized from 18S-rDNA analyses. Paramecium grohmannae sp. nov. is characterized by a unique combination of features. It is a counterclockwise rotating freshwater Paramecium with body outline intermediate between “aurelia” and “bursaria” forms, two contractile vacuoles, each with one excretion pore and usually nine collecting canals; oral opening slight below body equator; macronucleus ellipsoid to obovoid, measuring ~64 x 24 µm and located in anterior half of body; one (less frequently two) globular endosomal micronuclei
    [Show full text]
  • ​How Does Competition Affect Population Growth? Background the Genus Paramecium Spp
    Name: ___________________________________ Period: _______ ​How Does Competition Affect Population Growth? Background The genus Paramecium spp. consists of unicellular species of protists that live in freshwater environments. ​ ​ Under ideal conditions ­ enough food, water, and space ­ populations of these species grow rapidly and follow a pattern known as exponential growth. Exponential growth is explosive population growth in which the total ​ ​ number of potentially reproducing organisms increases with each generation. However, populations of organisms will not increase in size forever. Eventually, limitations on food, water, and other resources will cause the population to stop increasing. When a population arrives at the point where its size remains stable, it has reached the carrying capacity of the environment. The carrying capacity is the greatest number of individuals a given environment can sustain. ​ ​ Competition for resources among members of a population (intraspecific competition) places limits on population size. Competition for resources among members of two or more different species (interspecific competition) also ​ affects population size. In a classic series of experiments in the 1930s, a Russian ecologist, G.F. Gause, formulated his principle of competitive exclusion. This principle states that if two species are competing for ​ ​ the same resource, the species with a more rapid growth rate will outcompete the other. In other words, no two species can occupy the same niche (niche is defined as the feeding job of an organism). In competing populations of organisms, genetic variations that reduce competition are favored through natural selection. Suppose two species (A and B) compete for the same food source. Individuals of species A can also use another food source, which reduces the competition over the food source needed by species B.
    [Show full text]
  • Curriculum Vitae
    CURRICULUM VITAE January, 2019 Karl John Aufderheide Born: August 17, 1948, Minneapolis, MN Married: September 6, 1969 Spouse: Cheryl Wrolson Aufderheide Child: Karen Ruth Sysak (neé Aufderheide), born September 23, 1984 Education and Professional Experience B.S., summa cum laude Microbiology University of Minnesota June 1970 M.S. Cell Biology University of Minnesota July 1972 Ph.D. Cell Biology University of Minnesota Dec. 1974 Major Advisor: Dr. Ross Johnson Postdoctoral Study Indiana University Nov. 1974–Aug. 1977 Sponsor: Dr. Tracy Sonneborn Postdoctoral/Instructor University of Iowa Aug. 1977–Aug. 1979 Sponsor: Dr. Joseph Frankel Assistant Professor Texas A&M University Aug. 1979–Aug. 1986 Completion of Woods Hole course, “Optical Microscopy & Imaging in the Biomedical Sciences,” December, 1983 Senior Scientist, Institute of Developmental Biology, 1983–1985 Acting Director, Freshman Biology Program, Summer, 1983 Visiting Scholar Indiana University Aug.–Dec. 1986 Working in the laboratory of Dr. John Preer Associate Professor Texas A&M University Sept. 1986–Aug. 2018 Full Member, Graduate Faculty 1981– Associate Member, Genetics Faculty 1981–2000 Visiting Scholar Vanderbilt University Aug.–Dec. 2007 Working in the laboratory of Dr. Christopher Janetopoulos Emeritus Texas A&M University Sept. 2018– 2 Professional Interests Cell/Developmental Biology. Developmental Genetics. Intracellular differentiation of eukaryotes, especially ciliates. General interests in: intracellular pattern formation and morphogenesis; molecular aspects of
    [Show full text]
  • Taxaliste Der Gewässerorganismen Deutschlands Zur Kodierung
    Bayerisches Landesamt für Wasserwirtschaft (Herausgeber und Verlag) · München 2003 Taxaliste der Gewässer- organismen Deutschlands zur Kodierung biologischer Befunde Informationsberichte Heft 1/03 Informationsberichte des Bayerischen Landsamtes für Wasserwirtschaft Heft 01/03 München, 2003 – ISBN 3-930253-89-5 367 Seiten, 6 Abbildungen, 1 Tabelle, 1 CD, gedruckt auf chlorfrei gebleichtem Papier Herausgeber: Bayerisches Landesamt für Wasserwirtschaft, Lazarettstraße 67, D-80636 München, eine Behörde im Geschäftsbereich des Bayerischen Staatsministeriums für Landesentwicklung und Umweltfragen Autoren: Dr. Erik Mauch Dr. Ursula Schmedtje Dipl.-Ing (FH) Anette Maetze Dipl.-Biol. Folker Fischer Druck: Druckhaus Fritz König GmbH, München Bezug: Wasserwirtschaftsamt Deggendorf, Postfach 2061, 94460 Deggendorf Nachdruck und Wiedergabe – auch auszugsweise – nur mit Genehmigung des Herausgebers Vorwort Für die nationale und internationale Zusammenarbeit im Bereich der biologischen Gewässer- untersuchung ist die eindeutige Benennung und Kodierung der Gewässerorganismen entschei- dend. Diesem Zweck dient die „Taxaliste der Gewässerorganismen Deutschlands“, die hiermit erstmalig veröffentlicht wird. Die Liste enthält fast 10 000 in Deutschland vorkommende Gewässerorganismen der unterschied- lichsten limnischen Lebensräume. Jedem dieser Taxa wurde eine eindeutige Kennziffer zugewiesen. So ist es möglich, die Untersuchungsergebnisse innerhalb sowie zwischen den Flussgebieten in einheitlichen Datenbanken zusammenzufassen und auszuwerten. Damit stellt
    [Show full text]
  • Gause`S Principle with Field & Laboratory Examples Tig
    GAUSE`S PRINCIPLE WITH FIELD & LABORATORY EXAMPLES TIG The Competitive Exclusion Principle, or Gause's law, proposes that two species competing for the same limited resources cannot sustainably coexist or maintain constant population values. Intraspecific competition, describes when organisms within the same species compete for resources; leading the population to reach carryingcapacity. Carrying capacity refers to the maximum population size a species can sustain within its environmental limitations. Interspecific competition describes when competition for resources occurs between different species of organisms. Species can be limited by both their carrying capacity (intraspecific competition) and the interspecific competition. When two species compete within the same ecological niches, the Competitive Exclusion Principle predicts that the better adapted species, even if only slightly better adapted, will drive the other to local extinction. In the 1930s, biologist Georgy Gause explored the idea of interspecific competition in a ground-breaking study of competition in Paramecium. Paramecia are aquatic single-celled Ciliates that survive on a diet of Bacteria, Yeast, Algae, and other small protozoa. Based on the findings of this experiment and other research, Gause developed the Competitive Exclusion Principle. Direct or interference Competetion: Connel's field experiment on the rocky sea coast of Scotland, where larger Barnacle balanus dominates the intertidal area and removes the smaller Barnacle cathamalus. This happened due to competition for space between two species of barnacles, Balanus balanoides and Chthamalus stellatus. Though Chthamalus occupying an upper zone, and Balanus, a lower zone. Larvae of both species settle and attach over a wider vertical range than the zone occupied by adults. But barnacles are removed because Chthamalus are more tolerant of physical desiccation than Balanus.
    [Show full text]
  • Interactions How Can You Tell If Organisms Are Influencing Each
    Effect of interaction on growth rate of : Interactions How can you tell if organisms are influencing each other? Population/ Population/ • Intra-specific = interactions among members of the same Name of Interaction Species A Species B species/population. Neutralism (is this really 0 0 • Study the relationship between population growth rate and interaction?) • Inter-specific = interactions among members of different population density. Commensalism (table scraps) 0 + species. • If there is a relationship (either + or -), then assume that Mutualism or synergism + + the organisms are influencing each other, if not, there is no 0 - interaction (neutralism). Ammensalism + - Parasitism, predation - - Competition Competition Classic studies of resource competition by Gause (1934, 1935) A. Two major types: Resource competition can only occur when population growth rates of both individuals/populations/species are limited by the same resource. 1. Interference competition = Competition between two individuals/populations/species in which one physically or Paramecium chemically excludes the other from a habitat. If no resources are in limiting supply, then competition does caudatum not occur. 2. Resource competition = Occurs when use of a resource by Paramecium aurelia one individual/population/species reduces the availability of that resource to other individuals/populations. Paramecium bursaria 1 Gause found that interactions between Paramecium aurelia and P. caudatum always ended in competitive exclusion. In contrast, Paramecium bursia and P. caudatum could coexist. Because they inhabited different regions of the flask and ate different food. P. bursia fed on the bottom of the flask, and P. caudatum ate the bacteria in suspension. Within 14 days Paramecium aurelia In contrast, both P. aurelia and P.
    [Show full text]