Selective Bird Predation on the Peppered Moth: the Last Experiment of Michael Majerus

Total Page:16

File Type:pdf, Size:1020Kb

Selective Bird Predation on the Peppered Moth: the Last Experiment of Michael Majerus View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Harvard University - DASH Selective Bird Predation on the Peppered Moth: The Last Experiment of Michael Majerus The Harvard community has made this article openly available. Please share how this access benefits you. Your story matters. Citation Cook, Laurence M., Bruce S. Grant, Ilik J. Saccheri, and Jim Mallet. 2012. Selective bird predation on the peppered moth: The last experiment of michael majerus. Biology Letters 8, no. 4: 609-612. Published Version doi:10.1098/rsbl.2011.1136 Accessed February 19, 2015 10:47:02 AM EST Citable Link http://nrs.harvard.edu/urn-3:HUL.InstRepos:11210622 Terms of Use This article was downloaded from Harvard University's DASH repository, and is made available under the terms and conditions applicable to Other Posted Material, as set forth at http://nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms- of-use#LAA (Article begins on next page) Biol. Lett. (2012) 8, 609–612 took place in step with changing patterns of industrializ- doi:10.1098/rsbl.2011.1136 ation in Britain and elsewhere [3–5]. The melanic Published online 8 February 2012 ‘carbonaria’ morph is inherited via a dominant allele, Evolutionary biology C, at a single locus. The recessive c allele specifies the non-melanic black and white ‘typica’ form, while intermediate melanic ‘insularia’ alleles, inherited at the Selective bird predation on same locus, are dominant to typica and recessive to carbonaria. Insularia forms also increased, somewhat the peppered moth: the last variably, during industrialization [5]. Recently, this locus has been mapped and cloned; the pattern of gen- experiment of Michael etic variation in the genomic region harbouring the Majerus C locus suggests a rapid selective sweep around a single mutational origin of melanism [6]. L. M. Cook1, B. S. Grant2, I. J. Saccheri3 Melanics were long believed to be advantageous in and J. Mallet4,5,* the face of bird predation against bark resting sites dar- 1Life Sciences, University of Manchester, Manchester M13 9PT, UK kened by soot pollution [2], a form of camouflage [7]. 2Department of Biology, College of William and Mary, Williamsburg, Classic experiments in the mid-twentieth century VA 23187, USA proved that birds attacked the moths. Furthermore, rest- 3 Institute of Integrative Biology, University of Liverpool, ing moths that failed to match their background were Liverpool L69 7ZB, UK 4Genetics Evolution and Environment, UCL, 4 Stephenson Way, more vulnerable to bird predation in cage experiments London NW1 2HE, UK [8,9]. Mark–recapture studies of live moths, as well as 5Department of Organismic and Evolutionary Biology, Harvard many bird predation experiments using dead moths University, 26 Oxford Street, Cambridge, MA 02138, USA pinned to tree trunks, supported the hypothesis that *Author for correspondence ([email protected]). birds were the agents of selection on melanism [3,9]. Colour variation in the peppered moth Biston However, these procedures have drawbacks [3,5,10], betularia was long accepted to be under strong and critiques were increasingly aired [5,11,12]. In natural selection. Melanics were believed to be experiments, moths were often placed on tree trunks, fitter than pale morphs because of lower preda- which were argued to be abnormal resting sites; tion at daytime resting sites on dark, sooty bark. Melanics became common during the pinned carcases seemed particularly unnatural. Moths industrial revolution, but since 1970 there has were often released at greatly inflated densities, been a rapid reversal, assumed to have been potentially increasing predation. Reared insects from caused by predators selecting against melanics geographically distant sources were often used to sup- resting on today’s less sooty bark. Recently, plement wild individuals, and may not have behaved these classical explanations of melanism were as naturally in recapture experiments as wild moths. attacked, and there has been general scepticism By the 1990s, considerable scepticism became evident about birds as selective agents. Experiments [11–14]. Factors other than bird predation (e.g. and observations were accordingly carried out migration, physiological differences among genotypes) by Michael Majerus to address perceived weak- were argued to play a substantial role in the evolution nesses of earlier work. Unfortunately, he did not live to publish the results, which are analysed of melanism in Biston [5,15–17]. Caveats about the pre- and presented here by the authors. Majerus dation experiments discussed in Majerus’s book [5], released 4864 moths in his six-year experiment, critiques by other biologists, as well as points made par- the largest ever attempted for any similar study. ticularly forcefully in a review of the Majerus book [18], There was strong differential bird predation were soon exploited by non-scientists to promote an against melanic peppered moths. Daily selection anti-evolution agenda and to denigrate the predation against melanics (s 0.1) was sufficient in mag- explanation [10]. Kettlewell’s original mark–recapture nitude and direction to explain the recent rapid experiments were later argued to be fraudulent [19] decline of melanism in post-industrial Britain. (quite groundlessly: see [3,10,20]). Judith Hooper, These data provide the most direct evidence yet author of this claim, also suggested that bats rather to implicate camouflage and bird predation as than birds might be the agents of selection [19]. Soon, the overriding explanation for the rise and fall of melanism in moths. both the public in general and even evolutionary biol- ogists began to doubt the bird predation story Keywords: natural selection; cryptic coloration; (electronic supplementary material, S1 [18]). ecological genetics; insectivorous birds; melanism; Majerus therefore decided to make key new field lepidoptera observations, and he also designed and carried out a massive new predation experiment, the largest pre- dation experiment ever performed (4864 released 1. INTRODUCTION moths) to answer his own and other criticisms of Melanism in the peppered moth Biston betularia led to earlier work [5,10,21]. In addition, to address the the earliest measurements of natural selection on a Men- possible effect of bat predation, Majerus released live delian locus in the wild [1,2]. Rapid nineteenth century moths in night-time experiments in multiple locations: increases in melanics, followed by more recent declines he found no significant differences in predation of 419 melanic and typical moths eaten by three species of Electronic supplementary material is available at http://dx.doi.org/ pipistrelle bats [22]. 10.1098/rsbl.2011.1136 or via http://rsbl.royalsocietypublishing. org. Original source data from Majerus is given at http://dx.doi.org/ These results were all presented by Majerus in a 10.5061/dryad.962262h9 keynote address at the ESEB Congress, Uppsala, in Received 22 November 2011 Accepted 13 January 2012 609 This journal is q 2012 The Royal Society 610 L. M. Cook et al. Natural selection on melanism August 2007. Unfortunately, Majerus died after a Table 1. Numbers of wild peppered moths observed in short illness in 2009 before publishing the resting site different daytime resting positions, 2001–2006. Previous observations and predation results. However, the infor- authors had argued that moths rarely rested on tree trunks mation from the Uppsala talk, which forms the basis during the day, and that many predation experiments for the current analysis, was made freely available by employing tree trunks were therefore unnatural. In these new Majerus on the Internet soon thereafter as a set of pro- observations by Majerus, 35% of the 135 moths observed, both melanic and typical, were indeed found resting on jected slides. We have formed the current collaboration tree trunks. in order to analyse these results and disseminate them in print for the first time, as well as to clarify the impor- trunks branches twigs total tance of these key results for our understanding of natural selection in the wild. males 28 40 11 79 females 20 30 6 56 totals 48 70 17 135 2. MATERIAL AND METHODS Experimental and observational work presented here was carried out by Michael Majerus in a 1 ha rural garden, at Springfield, near His recent extensive observations on resting sites Coton, Cambridgeshire, UK. Full methods were published in a little-known chapter [10]; relevant extracts are provided here (elec- obtained while climbing the trees in his garden to set tronic supplementary material, S2). Original source files of his up the predation experiment appear to have been presentation in 2007, which contain the results analysed here, are lost, but he summarized the work in his 2007 provided at http://dx.doi.org/10.5061/dryad.962262h9. In cases Uppsala presentation (http: dx.doi.org/10.5061/ where numerical data were not supplied in these files, we have // expressed the results in terms similar to those used by Majerus in dryad.962262h9). An annotated version of this sum- the 2007 documents. mary is presented here. Majerus reported the following major features (table 1): (a) Natural resting sites While climbing trees in the experimental site in order to set up — The majority (52%) of moths rest on lateral sleeves for the predation experiment (see below), Majerus systemati- cally scrutinized trunks, branches and twigs of a limited set of trees branches. and recorded natural resting positions of all wild moths he found. — Of the moths on lateral branches, the majority The 135 observations he obtained here add considerably to the (89%) rest on the lower half of the branch. less-extensive resting site data previously published [10,12]. — A significant proportion of moths (35%) rest on (b) Predation experiment tree trunks. The purposes of the new experiment by Majerus were to estimate the — Of those that rest on trunks, the majority (87%) relative survival of local melanic and non-melanic moths at low, natur- rest on the north, rather than the south half.
Recommended publications
  • Why Much of What We Teach About Evolution Is Wrong/By Jonathan Wells
    ON SCIENCE OR MYTH? Whymuch of what we teach about evolution is wrong Icons ofEvolution About the Author Jonathan Wells is no stranger to controversy. After spending two years in the U.S. Ar my from 1964 to 1966, he entered the University of California at Berkeley to become a science teacher. When the Army called him back from reser ve status in 1968, he chose to go to prison rather than continue to serve during the Vietnam War. He subsequently earned a Ph.D. in religious studies at Yale University, where he wrote a book about the nineteenth­ century Darwinian controversies. In 1989 he returned to Berkeley to earn a second Ph.D., this time in molecular and cell biology. He is now a senior fellow at Discovery Institute's Center for the Renewal of Science and Culture (www.discovery.org/ crsc) in Seattle, where he lives with his wife, two children, and mother. He still hopes to become a science teacher. Icons ofEvolution Science or Myth? Why Much oJWhat We TeachAbout Evolution Is Wrong JONATHAN WELLS ILLUSTRATED BY JODY F. SJOGREN IIIIDIDIREGNERY 11MPUBLISHING, INC. An EaglePublishing Company • Washington, IX Copyright © 2000 by Jonathan Wells All rights reserved. No part of this publication may be reproduced or trans­ mitted in any form or by any means electronic or mechanical, including pho­ tocopy, recording, or any information storage and retrieval system now known or to be invented, without permission in writing from the publisher, except by a reviewer who wishes to quote brief passages in connection with a review written for inclusion in a magazine, newspaper, or broadcast.
    [Show full text]
  • Peppered Moths and the Industrial Revolution: Barking up the Wrong Tree? by Avril M
    NATIONAL CENTER FOR CASE STUDY TEACHING IN SCIENCE Peppered Moths and the Industrial Revolution: Barking up the Wrong Tree? by Avril M. Harder1, Janna R. Willoughby1,2, Jaqueline M. Doyle3 Part I – Hypotheses and Predictions The story of how Britain’s Industrial Revolution led to changes in peppered moth coloration is a classic, textbook ex- ample of evolution in action. You might even already be familiar with the plot and the findings of the main researcher of the phenomenon, H.B.D. Kettlewell. Although the peppered moth story has been told and re-told in thousands of biology classrooms, most narratives leave out an important bit of history: after Kettlewell published his results that described changes in morph population frequencies over time, many of his peers questioned the validity of his data. Your first task in this case study will be to put yourself in the place of one of Kettlewell’s contemporaries, evaluate his experimental methods, and decide whether his data support his assertions. Background Biston betularia is a medium-sized, nocturnal moth. Al- though the peppered moth is found across the world, some of the first research on this species was conducted in Great Britain. Before the Industrial Revolution, tree trunks in unpolluted areas were covered with lichens, and peppered moths with light colored wings were well camouflaged against this background (Figure 1). In this environment, light morphs vastly outnumbered dark morphs. During the Industrial Revolution, increasing air pollution led to the formation of acid rain and inhospitable conditions for the lichens. The death of the lichens combined with soot deposition on tree trunks led to an important environmen- tal shift for the moths.
    [Show full text]
  • Did Kettlewell Commit Fraud? Re-Examining The
    www.ssoar.info Did Kettlewell commit fraud? Re-examining the evidence Rudge, David Wÿss Postprint / Postprint Zeitschriftenartikel / journal article Zur Verfügung gestellt in Kooperation mit / provided in cooperation with: www.peerproject.eu Empfohlene Zitierung / Suggested Citation: Rudge, D. W. (2005). Did Kettlewell commit fraud? Re-examining the evidence. Public Understanding of Science, 14(3), 249-268. https://doi.org/10.1177/0963662505052890 Nutzungsbedingungen: Terms of use: Dieser Text wird unter dem "PEER Licence Agreement zur This document is made available under the "PEER Licence Verfügung" gestellt. Nähere Auskünfte zum PEER-Projekt finden Agreement ". For more Information regarding the PEER-project Sie hier: http://www.peerproject.eu Gewährt wird ein nicht see: http://www.peerproject.eu This document is solely intended exklusives, nicht übertragbares, persönliches und beschränktes for your personal, non-commercial use.All of the copies of Recht auf Nutzung dieses Dokuments. Dieses Dokument this documents must retain all copyright information and other ist ausschließlich für den persönlichen, nicht-kommerziellen information regarding legal protection. You are not allowed to alter Gebrauch bestimmt. Auf sämtlichen Kopien dieses Dokuments this document in any way, to copy it for public or commercial müssen alle Urheberrechtshinweise und sonstigen Hinweise purposes, to exhibit the document in public, to perform, distribute auf gesetzlichen Schutz beibehalten werden. Sie dürfen dieses or otherwise use the document in public. Dokument nicht in irgendeiner Weise abändern, noch dürfen By using this particular document, you accept the above-stated Sie dieses Dokument für öffentliche oder kommerzielle Zwecke conditions of use. vervielfältigen, öffentlich ausstellen, aufführen, vertreiben oder anderweitig nutzen. Mit der Verwendung dieses Dokuments erkennen Sie die Nutzungsbedingungen an.
    [Show full text]
  • A Critique of Evolution Within Catholicism and Its
    Approval Page J Donnelly i A CRITIQUE OF EVOLUTION WITHIN CATHOLICISM AND ITS SUBSEQUENT LINKS WITH FUNDAMENTAL CHRISTIANITY JOHN DONNELLY DIP.PHIL., B.D., H.DIP.ED., DIP. MISSION STUDIES, M.ED., FREEDOM BIBLE COLLEGE AND SEMINARY THESIS SUBMITTED TO THE DOCTORAL DISSERTATION COMMITTEE IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DOCTOR OF THEOLOGY DEGREE J Donnelly ii CONTENTS Page Acknowledgements iv Thesis Statement v Introduction 1 PART ONE: EVOLUTION AND CATHOLICISM Chapter 1: A Short History of Evolution Theory 3 Chapter 2: Evolution and Catholicism – The Current Position 34 Chapter 3: Can Evolution Blend with Catholicism? 54 Chapter 4: Why Evolution Can Never Become Part of Catholic Doctrine 66 Chapter 5: Why Catholics Should Reject Evolution 91 PART TWO: SOME PHILOSOPHICAL CONSIDERATIONS AND EFFECTS OF EVOLUTION WITHIN CATHOLICISM Chapter 6: Why Evolution is Pseudoscience – Some Philosophical Considerations 105 Chapter 7: Dangerous Effects of Evolution 130 Chapter 8: A Lesson from History 140 PART THREE: CATHOLICISM AND BIBLICAL CRITICISM – A NEED TO RETURN TO THE SCRIPTURES Chapter 9: Moses and the reliability of the Pentateuch 167 Chapter 10: Two Different Accounts in Genesis? 175 PART FOUR: CONCLUSION Chapter 11: Evolution, Catholicism and Fundamentalism 184 Bibliography 212 J Donnelly iii ACKNOWLEDGEMENTS I owe a huge debt of gratitude to the following people: Amy Joy Reilly who helped me with advice on editing; Vidis my wife who kept encouraging me when things were going slowly, enabling me to recommence; my parents John and Alice who also were a source of encouragement and who goaded me on; my pupils who were so interested in this theme and created even more enthusiasm in me; my daughter Clodagh who has never ceased to ask questions about evolution and kept me on my toes.
    [Show full text]
  • The Peppered Moth and Industrial Melanism: Evolution of a Natural Selection Case Study
    Heredity (2013) 110, 207–212 & 2013 Macmillan Publishers Limited All rights reserved 0018-067X/13 www.nature.com/hdy REVIEW The peppered moth and industrial melanism: evolution of a natural selection case study LM Cook1 and IJ Saccheri2 From the outset multiple causes have been suggested for changes in melanic gene frequency in the peppered moth Biston betularia and other industrial melanic moths. These have included higher intrinsic fitness of melanic forms and selective predation for camouflage. The possible existence and origin of heterozygote advantage has been debated. From the 1950s, as a result of experimental evidence, selective predation became the favoured explanation and is undoubtedly the major factor driving the frequency change. However, modelling and monitoring of declining melanic frequencies since the 1970s indicate either that migration rates are much higher than existing direct estimates suggested or else, or in addition, non-visual selection has a role. Recent molecular work on genetics has revealed that the melanic (carbonaria) allele had a single origin in Britain, and that the locus is orthologous to a major wing patterning locus in Heliconius butterflies. New methods of analysis should supply further information on the melanic system and on migration that will complete our understanding of this important example of rapid evolution. Heredity (2013) 110, 207–212; doi:10.1038/hdy.2012.92; published online 5 December 2012 Keywords: Biston betularia; carbonaria gene; mutation; predation; non-visual selection; migration INTRODUCTION EARLY EVIDENCE OF CHANGE The peppered moth Biston betularia (L.) and its melanic mutant will The peppered moth was the most diagrammatic example of the be familiar to readers of Heredity as an example of rapid evolutionary phenomenon of industrial melanism that came to be recognised in change brought about by natural selection in a changing environment, industrial and smoke-blackened parts of England in the mid-nine- evenifthedetailsofthestoryarenot.Infact,thedetailsarelesssimple teenth century.
    [Show full text]
  • A Natural History of Ladybird Beetles M
    Cambridge University Press 978-1-107-11607-8 — A Natural History of Ladybird Beetles M. E. N. Majerus , Executive Editor H. E. Roy , P. M. J. Brown Frontmatter More Information A Natural History of Ladybird Beetles The Coccinellidae are a family of beetles, known variously as ladybirds or ladybugs. In Britain alone, some 46 species belong to the Coccinellidae family, although only 26 of these are recognisably ladybirds. Composed largely of Professor Michael Majerus’ lifetime work, and updated by two leading experts in the field, this book reveals intriguing insights into ladybird biology from a global perspective. The popularity of this insect group has been captured through societal and cultural considerations coupled with detailed descriptions of complex scientific processes, to provide a comprehensive and accessible overview of these charismatic insects. Bringing together many studies on ladybirds, this book has been organised into themes ranging from anatomy and physiology to ecology and evolution. This book is suitable for interested amateur enthusiasts and researchers involved with ladybirds, entomology and biological control. Michael E.N. Majerus (1954–2009) was Professor of Genetics in the Department of Genetics at the University of Cambridge and Fellow of Clare College, Cambridge. He was a world authority in his field, a tireless advocate of evolution and an enthusiastic educator of graduate and undergraduate students. Helen Roy is a Group Head and Principal Scientist at the NERC Centre for Ecology & Hydrology, where she leads zoological research within the Biological Records Centre (UK focus for terrestrial and freshwater species recording). She is an ecologist with a particular interest in the effects of environmental change on insect communities.
    [Show full text]
  • Hdy199662.Pdf
    Heredity 76 (1996) 424—425 The Genetical Society of Great Britain Book reviews Ladybirds. Michael E. N. Majerus. Harper Collins, I have a few minor quibbles with the illustrations. The London. 1994. Pp. 367. Price £14.99, paperback. ISBN 16 colour plates are a useful feature of the book but their 0 00 219935 1. quality is variable. Also, some of the line drawings, for example those in Chapter 15, have a rather 'home-spun' The New Naturalist series has a long and distinguished look to them. However, these slight reservations aside, history spanning more than 80 volumes and 50 years. In Ladybirds is a worthy addition to a distinguished tradition. that time it has contained monographs that have become Apart from keen naturalists wishing to increase their classics and covered specialist topics on most areas of understanding of an intriguing group of beetles, the book British natural history. From the outset it has been char- will also attract professional biologists as a reference work acterized by attractive presentation and good populariza- which is more complete and much more recent than Ivo tion by experts, both professional and amateur. Michael Hodek's Biology of Coccinellidae. Even university geneti- Majerus's Ladybirds is an excellent addition to the long cists looking for good ideas for project students might find tradition of the series. The author himself acknowledges it useful. the first book in the series, E. B. Ford's Butterflies, as the DAVID R. LEES inspiration in his schooldays towards an interest, and later School of Pure and Applied Biology a career, in entomology and genetics.
    [Show full text]
  • The Peppered Moth: Decline of a Darwinian Disciple Michael E.N
    The Peppered moth: decline of a Darwinian disciple Michael E.N. Majerus Reader in Evolution, Department of Genetics, University of Cambridge Delivered to the British Humanist Association, at the London School of Economics, on Darwin Day, 12th February 2004. {Text links to powerpoint presentation, with slides indicated by PP numbers} PP1 Introduction The rise of the melanic moth The rise of the black, carbonaria form of the peppered moth, Biston betularia, in response to changes in the environment caused by the industrial revolution in Britain, is probably the best known example of evolution in action. The reasons for the prominence of this example are three-fold. First, the rise was spectacular, occurred in the recent and well-documented past, and was timely, the first record of an individual of carbonaria being published by Edelston (1864), just five years after the Origin of Species (Darwin, 1859). Second, the difference in the forms had visual impact. Third, the major mechanism through which carbonaria rose is easy to both relate and understand. The story, in brief, is this. The non-melanic peppered moth is a white moth, liberally speckled with black scales (PP2). In 1848, a black form, f. carbonaria (PP3), was recorded in Manchester, and by 1895, 98% of the Mancunian population were black (PP4). The carbonaria form spread to many other parts of Britain, reaching high frequencies in industrial centres and regions downwind. In 1896, the Lepidopterist, J.W. Tutt, hypothesized that the increase in carbonaria, was the result of differential bird predation in polluted regions. Bernard Kettlewell obtained evidence in support of this hypothesis in the 1950s, with his predation experiments in polluted and unpolluted woodlands.
    [Show full text]
  • MOTOR SYSTEMS Fect Orexactlytheoppositeeffect
    Outside JEB iv the brain and anterior regions of the leech Keeping track of the literature intact, while simultaneously recording from isnʼt easy, so Outside JEB is a E21 and motor nerves involved in monthly feature that reports the swimming. The front part of the leech was most exciting developments in placed in sensory environments ranging experimental biology. Short from deep water (to enhance swimming) to articles that have been selected solid substrate (to stimulate crawling). In and written by a team of active the watery environment, E21 went back to research scientists highlight the enhancing swim episodes exclusively. But papers that JEB readers canʼt when the animal was faced with solid afford to miss. ground, E21 activation initiated and enhanced crawling. This suggests that instead of rigidly commanding downstream circuits to do a single behavior, E21 cells are commanding motor circuits to do an appropriate behavior based on sensory cues. MOTOR SYSTEMS This effect was completely masked in isolated preparations lacking brains. LEECH BRAIN ADDS FLEXIBILITY TO COMMAND How does the presence of the brain add NEURON OUTPUT flexibility to the circuits called into play by Spinal cords and equivalent structures in E21? The team measured how descending invertebrates (nerve cords) often generate inputs from the brain affect the strength of rhythmic motor patterns without inputs a synapse between E21 and a downstream from sensory systems or the brain. cell type known to ‘gate’ swimming. Gating Preparations that generate such ‘fictive cell activity is required to maintain swim rhythms’ have been used to uncover episodes, so when the E21-to-gating cell properties of motor circuits in many synapse is weak, triggered swim episodes animals.
    [Show full text]
  • Discussion Questions Cookpaper
    Evolution BIOL 4510/5450 Journal Club Activity Discussion Questions on Selective bird predation on the peppered moth: the last experiment of Michael Majerus. by L. M. Cook, B. S. Grant, I. J. Saccheri & J. Mallet (2012) Biology Letters 8, 609–612 <http://rsbl.royalsocietypublishing.org/content/8/4/609> 1. Define and explain the following terms and concepts as they apply to this paper. • Melanism • Cryptic coloration • Ecological genetics • Selective agent • Dominant allele • Selective sweep • Mark – recapture • Resting site • Interpolation • Randomization • Heterogeneity • Null hypothesis • Kettlewell • Mendelian locus • Bats • Typicals • Contingency • Supplementary material 2. What animals were used in this study and how were they obtained and maintained for these experiments? Why were these particular animals selected for this study? 3. What parameters were measured and analyzed in this study? Be prepared to explain how Fig. 1 displays these parameters. 4. Explain the use and/or purpose of the following in this study. • Netting ‘sleeves' • Binoculars • Branches • Light traps • Naturalistic densities • Eclosion • Probability • Non-selective predation 5. For the predation experiment, answer the following questions: (1) The specific goal or question that was addressed: (2) The basic experimental design (what was manipulated and what was measured to answer the question): (3) The independent variables that were manipulated and their units of measurement, where applicable: (4) The dependent variables that were measured in response to the manipulations and their units of measurement: (5) The main take home message or finding associated with the following: o Fig. 1: o Table 2: (Hint: Experimental results are often (but not always) plotted in terms of how the dependent variable (as plotted on the vertical or y-axis) depends on the independent variable (as plotted on the horizontal or x-axis).
    [Show full text]
  • A Short History of the Theory of Evolution
    Chapter 1: A Short History of Evolution Theory Despite having its heritage in ancient Greece, the theory of evolution was first brought to the consideration of the scientific world in the nineteenth century. The most carefully considered view of evolution was expressed by the French biologist Jean-Baptiste Lamarck, in his Zoological Philosophy (1809). Lamarck thought that all living things were endowed with a vital force that steered them to evolve toward greater complexity. He also thought that organisms could impart to their offspring traits acquired during their lifetimes. As an example of this way of thinking, Lamarck suggested that the long neck of the giraffe evolved when a short-necked ancestor took to browsing on the leaves of trees instead of on grass. This evolutionary model of Lamarck's was invalidated by the discovery of the laws of genetic inheritance. In the middle of the twentieth century, the discovery of the structure of DNA revealed that the nuclei of the cells of living organisms possess very special genetic information, and that this could not be altered by ‘acquired traits’. In other words, during its lifetime, even though a giraffe managed to make its neck a few centimetres longer by extending it to upper branches, this trait would not pass to its offspring. In short, the Lamarckian view was simply refuted by scientific findings and went down in history as a faulty assumption. However, the evolutionary theory formulated by another natural scientist, who lived a couple of generations after Lamarck, proved to be more influential. This natural scientist was Charles Robert Darwin, and the theory he formulated is known as “Darwinism”.
    [Show full text]
  • Experiment of Michael Majerus Selective Bird
    Downloaded from rsbl.royalsocietypublishing.org on January 25, 2013 Selective bird predation on the peppered moth: the last experiment of Michael Majerus L. M. Cook, B. S. Grant, I. J. Saccheri and J. Mallet Biol. Lett. 2012 8, doi: 10.1098/rsbl.2011.1136 first published online 8 February 2012 Supplementary data "Data Supplement" http://rsbl.royalsocietypublishing.org/content/suppl/2012/01/31/rsbl.2011.1136.DC1.ht ml References This article cites 16 articles, 4 of which can be accessed free http://rsbl.royalsocietypublishing.org/content/8/4/609.full.html#ref-list-1 Article cited in: http://rsbl.royalsocietypublishing.org/content/8/4/609.full.html#related-urls This article is free to access Subject collections Articles on similar topics can be found in the following collections behaviour (573 articles) ecology (598 articles) environmental science (124 articles) evolution (602 articles) Receive free email alerts when new articles cite this article - sign up in the box at the top Email alerting service right-hand corner of the article or click here To subscribe to Biol. Lett. go to: http://rsbl.royalsocietypublishing.org/subscriptions Downloaded from rsbl.royalsocietypublishing.org on January 25, 2013 Biol. Lett. (2012) 8, 609–612 took place in step with changing patterns of industrializ- doi:10.1098/rsbl.2011.1136 ation in Britain and elsewhere [3–5]. The melanic Published online 8 February 2012 ‘carbonaria’ morph is inherited via a dominant allele, Evolutionary biology C, at a single locus. The recessive c allele specifies the non-melanic black and white ‘typica’ form, while intermediate melanic ‘insularia’ alleles, inherited at the Selective bird predation on same locus, are dominant to typica and recessive to carbonaria.
    [Show full text]