DOCSLIB.ORG

Molecular Evolution of Visual System Genes in Fishes

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Molecular Evolution of Visual System Genes in Fishes Molecular Evolution of Visual System Genes in Fishes by Cameron James Weadick A thesis submitted in conformity with the requirements for the degree of Doctor of Philosophy Ecology and Evolutionary Biology University of Toronto © Copyright by Cameron James Weadick 2012 Molecular Evolution of Visual System Genes in Fishes Cameron James Weadick Doctor of Philosophy Ecology and Evolutionary Biology University of Toronto 2012 Abstract For many species, vision contributes to a number of fitness-related tasks, including mating and the detection of prey and predators. Selection on the visual system should therefore be strong, especially when ecological or genomic changes open new avenues for evolutionary changes. Visual system proteins are thus attractive systems for molecular evolutionary analyses. This thesis presents a collection of evolutionary studies on two gene families, opsins and crystallins. Opsin proteins determine the wavelengths of light detected by the retina, while crystallin proteins contribute to lens transparency and refractory power. My studies focus on teleost fishes, because teleost visual ecology is exceptionally diverse and because gene duplication is common in this group. In Chapter One, I outline the relevance of protein variation to organismal evolution and describe the analytical methods employed throughout this thesis. Chapter Two considers the long- wavelength sensitive (LWS) opsins of the guppy (Poecilia reticulata). The guppy is shown to possess multiple LWS opsins that have accumulated differences at functionally important amino acid sites since duplicating. Chapter Three focuses on the guppy’s main predator, the pike cichlid Crenicichla frenata, which is shown to have a greater capacity for short-wavelength vision than previously believed. However, this cichlid possesses three fewer opsins than closely- ii related African cichlids, a difference partly due to duplication of a green-sensitive (RH2) opsin in African cichlids. In Chapter Four, this RH2 duplication event is studied in greater depth; variation in selective constraint is documented following gene duplication and between species from different lakes. Some of the analytical methods employed in Chapter Four were newly developed, as detailed in Chapter Five, where a test for functional divergence among clades is evaluated and then improved upon through the presentation of a new null model that better accommodates among-site variation in selection. In Chapter Six, phylogenetic relationships within the βγ lens crystallin superfamily are clarified, and the functionally distinct γN family is shown to have evolved conservatively compared to other crystallin families. The thesis concludes with suggestions for future directions for evolutionary research on opsins and crystallins, and summarizes recent work that has built on these studies. iii Acknowledgments First and foremost, I would like to thank Belinda Chang and Helen Rodd, my co-supervisors, for their support (academic, financial, and otherwise) throughout my PhD. I learned a great deal from both of them and they graciously provided me enough rope to nearly hang myself on several occasions. I hope they forgive my occasional stubbornness, my late-night half-panicked emails, and the fact that I couldn't quite cut it as a behavioural ecologist. Asher Cutter and Allan Baker filled out my supervisory committee. I thank them both for their feedback and for humouring me as I more-or-less introduced a new study system every committee meeting and thesis chapter. Asher deserves extra thanks for reading over my entire thesis and for serving on my final examination committee. I would also like to acknowledge Marla Sokolowski, Locke Rowe, and David Guttman for serving on my various committees and for keeping me honest about the reach of my thesis work (and for doing so nicely). Karen Carleton graciously traveled to Toronto in November to be my external examiner and let it slide that a solid chunk of my thesis involves analyzing her old data; that was very much appreciated. Ellis Loew is thanked for carrying out the MSP analyses presented in Chapter Three and for doing so with barely any forewarning, while Ziheng Yang is thanked for providing assistance (unknowingly, via the PAML discussion forum) on modifying his codeml program's source code and for subsequently agreeing to include the results of my work in his software. I also acknowledge the various members of the Chang and Rodd labs who helped keep the labs running despite my slovenly, nocturnal ways, as well as Dimitra Kolovos and the various members of the ROM and CAGEF sequencing centers for providing me with precious data. More generally, the EEB department and some very generous funding sources (including from NSERC and U. Toronto’s VSRP) helped keep me afloat and occasionally productive. Beyond my thesis work, I was fortunate to become involved in a number of side projects with other students and faculty members. For that, I'd like to recognize Kat Hult and Steve Tobe, Loksum Wong and Vince Tropepe, Alex de Serrano and Anna Price, and Yayi Huang and iv Francesco Santini. If I'd no choice but to work solely on my thesis this long while I'd have surely lost my mind. All are thanked for letting me join in these productive distractions. On that note, I must also thank the many incredible grad students and postdocs kind enough to share a word and a drink with me over these last several years. I'd list them all, but there are too many, by far, and I'm afraid I'd foolishly miss a key name or three. They're all quite awesome, and I hope they know that. My lab mates in the Rodd and Chang labs deserve special note, as do my office mates in RW507 and RW415. But, here, I'd just like to note Anna Price and Ilke van Hazel for years of friendship and for helping me survive my initially terrifying (but ultimately rewarding) foray into big city living. My family was incredibly supportive throughout this entire process despite the fact that I never was able to really explain what it was I was doing to any degree of satisfaction, or what it was that I might end up doing afterwards. They certainly deserved more phone calls and visits than I gave, and I hope they don't hold that against me. The same goes for my friends made before grad school, many of whom are long lost, yet still appreciated greatly. Finally, thanks must go, of course, to Bonnie Fraser, my partner in pretty much everything. I'm quite sure that she's the absolute tops. Bonnie, thank you so much for believing in me, and thank you so much for waiting for me. v Statement of Contributions Chapters Two and Six were published as co-authored papers with my co-supervisor, Belinda Chang. Chapters Three through Five are co-authored manuscripts that are currently being prepared for journal submission. Chapters Four and Five were also co-authored by Belinda, while Chapter Three was co-authored by Belinda, my other co-supervisor, Helen Rodd, and Professor Ellis Loew (Cornell University), who carried out the microspectrophotometric analyses. In each case, I carried out the bulk of data collection, analyses, and writing; study/experimental designs were devised in consultation with one or both of my co-supervisors. vi Table of Contents Acknowledgments iv Statement of Contributions vi Table of Contents vii List of Tables x List of Figures xi Chapter 1 Introduction 1 1.1 Protein Evolution and its Organismal Relevance 2 1.2 Gene Duplication and Divergence 4 1.3 Detecting Selection in Protein-coding Genes 6 1.4 The Molecular Biology of Vertebrate Vision 12 1.5 Visual Ecology in Guppies and Cichlids 16 1.6 Thesis Overview 18 1.7 References 19 Chapter 2 Long-wavelength Sensitive Visual Pigments of the Guppy (Poecilia reticulata): Six Opsins Expressed in a Single Individual 24 2.1 Introduction 26 2.2 Results and Discussion 29 2.3 Conclusions 35 2.4 Methods 36 2.5 Figures 39 2.6 Tables 45 2.7 References 48 2.8 Supplementary Material 52 Chapter 3 Characterizing the Visual Pigments of the Trinidadian Pike Cichlid (Crenicichla frenata): A Less Colourful World for Neotropical Cichlids? 54 vii 3.1 Introduction 55 3.2 Methods 58 3.3 Results 65 3.4 Discussion 72 3.5 Figures 78 3.6 Tables 85 3.7 References 89 3.8 Supplementary Material 95 Chapter 4 Molecular evolutionary analysis of duplicated RH2a opsins in African cichlids 114 4.1 Introduction 115 4.2 Methods 118 4.3 Results 124 4.4 Discussion 131 4.5 Figures 136 4.6 Tables 141 4.7 References 148 4.8 Supplementary Material 152 Chapter 5 An improved likelihood ratio test for detecting site-specific functional divergence among clades of protein-coding genes 163 5.1 Introduction 164 5.2 Methods 167 5.3 Results and Discussion 171 5.4 Conclusions 178 5.5 Figures 179 5.6 Tables 181 5.7 References 185 5.8 Supplementary Material 188 viii Chapter 6 Molecular Evolution of the βγ Lens Crystallin Superfamily: Evidence for a Retained Ancestral Function in γN Crystallins? 195 6.1 Introduction 197 6.2 Methods 200 6.3 Results 206 6.4 Discussion 213 6.5 Figures 220 6.6 Tables 224 6.7 References 230 6.8 Supplementary Material 236 Chapter 7 Conclusions 249 7.1 Chapter 2: Guppy long-wavelength sensitive (LWS) opsins 250 7.2 Chapter 3: Trinidadian pike cichlid opsins 256 7.3 Chapter 4: Duplicated African cichlid green sensitive (RH2a) opsins 259 7.4 Chapter 5: Clade model likelihood ratio testing 261 7.5 Chapter 6: βγ lens crystallin superfamily 263 7.6 Summary 265 7.7 References 266 ix List of Tables Table 2.1 ........................................................................................................... 45 Table 2.2 ........................................................................................................... 47 Supplementary Table 2.1 .................................................................................
Load more

Recommended publications
  • §4-71-6.5 LIST of CONDITIONALLY APPROVED ANIMALS November
    §4-71-6.5 LIST OF CONDITIONALLY APPROVED ANIMALS November 28, 2006 SCIENTIFIC NAME COMMON NAME INVERTEBRATES PHYLUM Annelida CLASS Oligochaeta ORDER Plesiopora FAMILY Tubificidae Tubifex (all species in genus) worm, tubifex PHYLUM Arthropoda CLASS Crustacea ORDER Anostraca FAMILY Artemiidae Artemia (all species in genus) shrimp, brine ORDER Cladocera FAMILY Daphnidae Daphnia (all species in genus) flea, water ORDER Decapoda FAMILY Atelecyclidae Erimacrus isenbeckii crab, horsehair FAMILY Cancridae Cancer antennarius crab, California rock Cancer anthonyi crab, yellowstone Cancer borealis crab, Jonah Cancer magister crab, dungeness Cancer productus crab, rock (red) FAMILY Geryonidae Geryon affinis crab, golden FAMILY Lithodidae Paralithodes camtschatica crab, Alaskan king FAMILY Majidae Chionocetes bairdi crab, snow Chionocetes opilio crab, snow 1 CONDITIONAL ANIMAL LIST §4-71-6.5 SCIENTIFIC NAME COMMON NAME Chionocetes tanneri crab, snow FAMILY Nephropidae Homarus (all species in genus) lobster, true FAMILY Palaemonidae Macrobrachium lar shrimp, freshwater Macrobrachium rosenbergi prawn, giant long-legged FAMILY Palinuridae Jasus (all species in genus) crayfish, saltwater; lobster Panulirus argus lobster, Atlantic spiny Panulirus longipes femoristriga crayfish, saltwater Panulirus pencillatus lobster, spiny FAMILY Portunidae Callinectes sapidus crab, blue Scylla serrata crab, Samoan; serrate, swimming FAMILY Raninidae Ranina ranina crab, spanner; red frog, Hawaiian CLASS Insecta ORDER Coleoptera FAMILY Tenebrionidae Tenebrio molitor mealworm,
    [Show full text]
  • Sex Differences in Visual Perception in Melanochromis Auratus
    SEX DIFFERENCES IN VISUAL PERCEPTION IN MELANOCHROMIS AURATUS Margaret Coniam A Thesis Submitted to the Graduate College of Bowling Green State University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE August 2014 Committee: Moira van Staaden, Advisor Sheryl Coombs Robert Huber ii ABSTRACT Moira van Staaden, Advisor The cichlid fishes of Lake Malawi have undergone explosive speciation in the past 1.5 million years with the production of between 500-1000 species of cichlid 1. Sensory factors such as visual, olfactory and acoustic signals are all believed to play a role in this differentiation process. Vision is by far the most studied and best understood of the sensory modalities, but there is a distinct gap between our understanding of the molecular components of the cichlid visual system and whether, or how exactly, these impact the behavior displayed. Recent research has shown that the type of visual pigment expressed in the retina differs by sex in Melanochromis auratus 11. We aimed to determine whether such differences are reflected in sex- dependent variation in hue sensitivity and hue discrimination in M. auratus. To test this, we used a modified optomotor discrimination task to assess (i) differences in the luminance curves for each sex and (ii) sex differences in the minimum angular distance of adjacent hues required to elicit recognition as two distinct stimuli. Our results indicate significant variation in the minimum brightness required for the perception of hues across the color spectrum, but no sex- specific difference in detection thresholds. Similarly, results for the minimum angular distance required to discriminate between adjacent hues suggest there are areas of the color spectrum to which vision is tuned, but again no difference between the sexes.
    [Show full text]
  • Evidence for Adaptation, Reinforcement Or Sexual Selection
    Japan. J. Ichthyol. 4 0 ( 1): 15- 21, 1993 4 0 ( 1): 15- 21, 1993 Sexual Selection and Genetic Relationships of a Sibling Species Complex of Bower Building Cichlids in Lake Malawi, Africa Kenneth R. McKaye,1 James H. Howard,2 Jay R. Stauffer, Jr.,3 Raymond P. Morgan II1 and Fortune Shonhiwa4 1 Appalachian Environmental Laboratory, Center for Estuarine and Environmental Studies, University of Maryland, Frostburg, MD 21532, USA 2 Department of Biology, Frostburg State University, Frostburg, MD 21532, USA 3 School of Forest Resources, Pennsylvania State University, University Park, PA 16802, USA 4 Department of National Parks and Wildlife Management, Harare, Zimbabwe (Received December 16, 1992; in revised form January 10, 1993; accepted February 18, 1993) Abstract Protein electromorphs of five taxa of the sand dwelling genus Tramitichromis from Lake Malawi were examined by starch-gel electrophoresis. Twenty-four enzyme loci were examined. No diagnostic alleles were discovered which distinguished the different taxa; however, nine loci were polymorphic in at least one taxa with unbiased mean heterozygosities ranging from 6.9 to 12.6%. The bower form of these five taxa, which earlier have been referred to as sibling species was also analyzed. Results from this study provide evidence that bower form in these cichlid taxa is correlated with genetic distance measurements. The data suggest that the taxa are isolated ‘sibling’ species, which recently diverged, or that they are ‘incipient’ species with minimal gene flow between bower building morphs. The congruence of the allozyme data suggests a genetic basis for bower form. Variation in bower form is hypothesized to arise from nonadaptive differences in female choice, which leads to reproductively isolated species as predicted by Fisher’s model of runaway sexual selection.
    [Show full text]
  • Ophthalmotilapia Boops (BOULENGER, 1901)
    DCG_Info_05_2016_HR_20160420_Karlsson_ohne_Haustein_DCG_Info 20.04.2016 06:36 Seite 106 Ophthalmotilapia boops (BOULENGER, 1901) Wolfgang Staeck Abb. 1. Männchen von Ophthalmotilapia boops über seiner Laichgrube auf einem Felsen bei Kampemba Point (Kleines Bild: Ophthalmotilapia boops und Tropheus bei Kampemba Point) Meine erste Begegnung mit diesem un- Beide sprachen kein Englisch, sondern geografische Farbvariante von Oph- gewöhnlichen Tanganjikasee-Bunt- unterhielten sich gewöhnlich auf Sua- thalmotilapia ventralis hielt, zu fangen, barsch liegt nun bereits fast vierzig heli, das ich nicht beherrschte. Da in weil wir nicht über die dazu benötigte Jahre zurück. Im Jahre 1977 bereiste Burundi aber neben der afrikanischen Ausrüstung verfügten, um sie heil bis ich zusammen mit zwei Fängern des Muttersprache auch Französisch ge- in das weit entfernte Kigoma zu trans- damals in Dar es Salaam lebenden Ex- sprochen wurde, war die Kommunika- portieren. porteurs Misha Fainzilber in einem der tion in unserer kleinen Reisegruppe dort üblichen motorisierten Fischer- kein unlösbares Problem. Systematik und Merkmale von Oph- boote von Kigoma aus die zu Tansania thalmotilapia gehörende Ostküste des Tanganjikasees Ich erinnere mich noch genau über in südlicher Richtung bis nach Kipili. meine Begeisterung, als ich in der Um- Ophthalmotilapia boops gehört zu den Ziel unserer fast drei Wochen dauern- gebung der Ortschaft Kipili schnor- ersten Arten, die aus dem Tanganjika- den Entdeckungsreise war es, für den chelte und dort im Uferbereich der see beschrieben wurden, denn die bei- Exporteur eine erste Bestandsaufnahme Insel Kerenge erstmals die auffallend den Typusexemplare sind von dem der in diesem Gebiet vorkommenden kontrastreich tief schwarz und leuch- englischen Forschungsreisenden MOORE Buntbarsche vorzunehmen. tend hellblau gezeichneten Männchen bereits gegen Ende des 19.
    [Show full text]
  • Cichlid Diversity, Speciation and Systematics: Examples from the Great African Lakes
    Cichlid diversity, speciation and systematics: examples from the Great African Lakes Jos Snoeks, Africa Museum, Ichthyology- Cichlid Research Unit, Leuvensesteenweg 13, B-3080 Ter­ vuren,.Belgium. Tel: (32) 2 769 56 28, Fax: (32) 2 769 56 42(e-mail: [email protected]) ABSTRACT The cichlid faunas of the large East African lakes pro vide many fascina ting research tapies. They are unique because of the large number of species involved and the ir exceptional degree ofendemicity. In addition, certain taxa exhibit a substantial degree of intra~lacustrine endemism. These features al one make the Great African Lakes the largest centers of biodiversity in the vertebrate world. The numbers of cichlid species in these lakes are considered from different angles. A review is given of the data available on the tempo of their speciation, and sorne of the biological implications of its explosive character are discussed. The confusion in the definition of many genera is illustrated and the current methodology of phylogenetic research briefly commented upon. Theresults of the systematic research within the SADC/GEFLake Malawi/NyasaBiodiversity Conservation Project are discussed. It is argued that systematic research on the East African lake cichlids is entering an era of lesser chaos but increasing complexity. INTRODUCTION The main value of the cichlids of the Great African Grea ter awareness of the scientific and economi­ Lakes is their economie importance as a readily cal value of these fishes has led to the establishment accessible source of protein for the riparian people. In of varioüs recent research projects such as the three addition, these fishes are important to the specialized GEF (Global Environmental Facility) projects on the aquarium trade as one of the more exci ting fish groups larger lakes (Victoria, Tanganyika, Malawi/Nyasa).
    [Show full text]
  • The Behavioral Ecology of the Tibetan Macaque
    Fascinating Life Sciences Jin-Hua Li · Lixing Sun Peter M. Kappeler Editors The Behavioral Ecology of the Tibetan Macaque Fascinating Life Sciences This interdisciplinary series brings together the most essential and captivating topics in the life sciences. They range from the plant sciences to zoology, from the microbiome to macrobiome, and from basic biology to biotechnology. The series not only highlights fascinating research; it also discusses major challenges associ- ated with the life sciences and related disciplines and outlines future research directions. Individual volumes provide in-depth information, are richly illustrated with photographs, illustrations, and maps, and feature suggestions for further reading or glossaries where appropriate. Interested researchers in all areas of the life sciences, as well as biology enthu- siasts, will find the series’ interdisciplinary focus and highly readable volumes especially appealing. More information about this series at http://www.springer.com/series/15408 Jin-Hua Li • Lixing Sun • Peter M. Kappeler Editors The Behavioral Ecology of the Tibetan Macaque Editors Jin-Hua Li Lixing Sun School of Resources Department of Biological Sciences, Primate and Environmental Engineering Behavior and Ecology Program Anhui University Central Washington University Hefei, Anhui, China Ellensburg, WA, USA International Collaborative Research Center for Huangshan Biodiversity and Tibetan Macaque Behavioral Ecology Anhui, China School of Life Sciences Hefei Normal University Hefei, Anhui, China Peter M. Kappeler Behavioral Ecology and Sociobiology Unit, German Primate Center Leibniz Institute for Primate Research Göttingen, Germany Department of Anthropology/Sociobiology University of Göttingen Göttingen, Germany ISSN 2509-6745 ISSN 2509-6753 (electronic) Fascinating Life Sciences ISBN 978-3-030-27919-6 ISBN 978-3-030-27920-2 (eBook) https://doi.org/10.1007/978-3-030-27920-2 This book is an open access publication.
    [Show full text]
  • And Giant Guitarfish (Rhynchobatus Djiddensis)
    VIRAL DISCOVERY IN BLUEGILL SUNFISH (LEPOMIS MACROCHIRUS) AND GIANT GUITARFISH (RHYNCHOBATUS DJIDDENSIS) BY HISTOPATHOLOGY EVALUATION, METAGENOMIC ANALYSIS AND NEXT GENERATION SEQUENCING by JENNIFER ANNE DILL (Under the Direction of Alvin Camus) ABSTRACT The rapid growth of aquaculture production and international trade in live fish has led to the emergence of many new diseases. The introduction of novel disease agents can result in significant economic losses, as well as threats to vulnerable wild fish populations. Losses are often exacerbated by a lack of agent identification, delay in the development of diagnostic tools and poor knowledge of host range and susceptibility. Examples in bluegill sunfish (Lepomis macrochirus) and the giant guitarfish (Rhynchobatus djiddensis) will be discussed here. Bluegill are popular freshwater game fish, native to eastern North America, living in shallow lakes, ponds, and slow moving waterways. Bluegill experiencing epizootics of proliferative lip and skin lesions, characterized by epidermal hyperplasia, papillomas, and rarely squamous cell carcinoma, were investigated in two isolated poopulations. Next generation genomic sequencing revealed partial DNA sequences of an endogenous retrovirus and the entire circular genome of a novel hepadnavirus. Giant Guitarfish, a rajiform elasmobranch listed as ‘vulnerable’ on the IUCN Red List, are found in the tropical Western Indian Ocean. Proliferative skin lesions were observed on the ventrum and caudal fin of a juvenile male quarantined at a public aquarium following international shipment. Histologically, lesions consisted of papillomatous epidermal hyperplasia with myriad large, amphophilic, intranuclear inclusions. Deep sequencing and metagenomic analysis produced the complete genomes of two novel DNA viruses, a typical polyomavirus and a second unclassified virus with a 20 kb genome tentatively named Colossomavirus.
    [Show full text]
  • Bar, Stripe and Spot Development in Sand-Dwelling Cichlids from Lake Malawi
    Hendrick et al. EvoDevo (2019) 10:18 https://doi.org/10.1186/s13227-019-0132-7 EvoDevo RESEARCH Open Access Bar, stripe and spot development in sand-dwelling cichlids from Lake Malawi Laura A. Hendrick1, Grace A. Carter1, Erin H. Hilbrands1, Brian P. Heubel1, Thomas F. Schilling2 and Pierre Le Pabic1* Abstract Background: Melanic patterns such as horizontal stripes, vertical bars and spots are common among teleost fshes and often serve roles in camoufage or mimicry. Extensive research in the zebrafsh model has shown that the devel- opment of horizontal stripes depends on complex cellular interactions between melanophores, xanthophores and iri- dophores. Little is known about the development of horizontal stripes in other teleosts, and even less is known about bar or spot development. Here, we compare chromatophore composition and development of stripes, bars and spots in two cichlid species of sand-dwellers from Lake Malawi—Copadichromis azureus and Dimidiochromis compressiceps. Results: (1) In D. compressiceps, stripes are made of dense melanophores underlaid by xanthophores and overlaid by iridophores. Melanophores and xanthophores are either loose or absent in interstripes, and iridophores are dense. In C. azureus, spots and bars are composed of a chromatophore arrangement similar to that of stripes but are separated by interbars where density of melanophores and xanthophores is only slightly lower than in stripes and iridophore density appears slightly greater. (2) Stripe, bar and spot chromatophores appear in the skin at metamorphosis. Stripe melanophores directly diferentiate along horizontal myosepta into the adult pattern. In contrast, bar number and position are dynamic throughout development. As body length increases, new bars appear between old ones or by splitting of old ones through new melanophore appearance, not migration.
    [Show full text]
  • Ancistrus Dolichopterus) in Aquarium Conditions
    LIMNOFISH-Journal of Limnology and Freshwater Fisheries Research 6(3): 231-237 (2020) A Preliminary Study on Reproduction and Development of Bushymouth Catfish (Ancistrus dolichopterus) in Aquarium Conditions Mustafa DENİZ1* , T. Tansel TANRIKUL2 , Onur KARADAL3 , Ezgi DİNÇTÜRK2 F. Rabia KARADUMAN 1 1Department of Aquaculture, Graduate School of Natural and Applied Sciences, İzmir Kâtip Çelebi University, 35620, Çiğli, İzmir, Turkey 2Department of Fish Diseases, Faculty of Fisheries, İzmir Kâtip Çelebi University, 35620, Çiğli, İzmir, Turkey 3Department of Aquaculture, Faculty of Fisheries, İzmir Kâtip Çelebi University, 35620, Çiğli, İzmir, Turkey ABSTRACT ARTICLE INFO Dwarf suckermouth catfish are preferred especially for small aquariums. They are RESEARCH ARTICLE usually referred to as tank cleaners and commonly traded in the ornamental fish sector. Since these fish are nocturnal, it is difficult to observe their reproductive Received : 28.02.2020 behavior and larval development. This study was carried out to determine the Revised : 05.06.2020 reproductive variables of bushymouth catfish (Ancistrus dolichopterus) under aquarium conditions. Three broodstocks bushymouth catfish with an average Accepted : 09.06.2020 initial weight and a total length of 10.5±0.3 g and 9.5±0.2 cm were stocked in Published : 29.12.2020 three 240-L aquariums with the ratio of 1:2 (male: female). The observations were made in triplicate tanks for six months. Females laid an average of 39.78±0.41 DOI:10.17216/LimnoFish.695413 eggs and fertilization and hatching rates were 75.05% and 62.94%, respectively. It was found that the transition time from egg to apparently larval stage was * CORRESPONDING AUTHOR 105.28 h, and bushymouth catfish showed an indistinguishable development from [email protected] the hatching to juvenile stage without a real larval transition stage.
    [Show full text]
  • The Role of Flow Sensing by the Lateral Line System in Prey Detection in Two African Cichlid Fishes
    University of Rhode Island DigitalCommons@URI Open Access Dissertations 9-2013 THE ROLE OF FLOW SENSING BY THE LATERAL LINE SYSTEM IN PREY DETECTION IN TWO AFRICAN CICHLID FISHES Margot Anita Bergstrom Schwalbe University of Rhode Island, [email protected] Follow this and additional works at: https://digitalcommons.uri.edu/oa_diss Recommended Citation Schwalbe, Margot Anita Bergstrom, "THE ROLE OF FLOW SENSING BY THE LATERAL LINE SYSTEM IN PREY DETECTION IN TWO AFRICAN CICHLID FISHES" (2013). Open Access Dissertations. Paper 111. https://digitalcommons.uri.edu/oa_diss/111 This Dissertation is brought to you for free and open access by DigitalCommons@URI. It has been accepted for inclusion in Open Access Dissertations by an authorized administrator of DigitalCommons@URI. For more information, please contact [email protected]. THE ROLE OF FLOW SENSING BY THE LATERAL LINE SYSTEM IN PREY DETECTION IN TWO AFRICAN CICHLID FISHES BY MARGOT ANITA BERGSTROM SCHWALBE A DISSERTATION SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY IN BIOLOGICAL SCIENCES UNIVERSITY OF RHODE ISLAND 2013 DOCTOR OF PHILOSOPHY DISSERTATION OF MARGOT ANITA BERGSTROM SCHWALBE APPROVED: Dissertation Committee: Major Professor Dr. Jacqueline Webb Dr. Cheryl Wilga Dr. Graham Forrester Dr. Nasser H. Zawia DEAN OF THE GRADUATE SCHOOL UNIVERSITY OF RHODE ISLAND 2013 ABSTRACT The mechanosensory lateral line system is found in all fishes and mediates critical behaviors, including prey detection. Widened canals, one of the four patterns of cranial lateral line canals found among teleosts, tend to be found in benthic fishes and/or fishes that live in hydrodynamically quiet or light-limited environments, such as the deep sea.
    [Show full text]
  • Sex-Specific Aggressive Decision-Making in the African Cichlid Melanochromis Auratus
    SEX-SPECIFIC AGGRESSIVE DECISION-MAKING IN THE AFRICAN CICHLID MELANOCHROMIS AURATUS Kamela De Stamey A Thesis Submitted to the Graduate College of Bowling Green State University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE August 2014 Committee: Moira van Staaden, Advisor Daniel Wiegmann Sheryl Coombs © 2014 Enter your First and Last Name All Rights Reserved iii ABSTRACT Moira van Staaden, Advisor Effective fighting strategies are essential to successfully navigate competitive social interactions. Probing the fighting ability of opponents requires that individuals employ assessment behaviors so that appropriate decisions about fighting strategies can be made. Inherent properties, such as sex and body size, have the potential to influence tactical fighting choices. African cichlids are well known for their hyper-aggressive nature and make ideal models for probing the underlying factors that impact decision-making during aggressive encounters. Here, an ethogram was constructed comprising seventeen behaviors to probe the sex- and size- related differences in the fighting decisions of same-sex pairs of Melanochromis auratus, a highly territorial Malawian cichlid. A modified Mirror Image Stimulation (MMIS) test was developed that utilized mirrors with curved surfaces to query sex-dependent strategies based on altered apparent opponent size. Differential behavior based on the sex of the fish was also observed in staged encounters of size-matched dyads. Males showed little progressive assessment behavior and instead engaged in immediate and intense fighting, whereas females exhibit longer latencies to engage opponents and prolonged assessment phases. The sexes also exhibited distinct, but different, size-dependent strategies. During MMIS, males bit and displayed at higher rates towards larger mirror-image opponents, while female responses were more circumspect.
    [Show full text]
  • Gonad Development in Midas Cichlids and the Evolution of Sex Change in Fishes
    EVOLUTION & DEVELOPMENT 13:4, 352–360 (2011) DOI: 10.1111/j.1525-142X.2011.00490.x Gonad development in Midas cichlids and the evolution of sex change in fishes Ronald G. OldfieldÃ,1 University of Michigan, Department of Ecology and Evolutionary Biology, Museum of Zoology, 1109 Geddes Ave., Ann Arbor, MI 48109, USA ÃAuthor for correspondence (email: [email protected]) 1Present address: Case Western Reserve University, Department of Biology, 10900 Euclid Ave., Cleveland, OH 44106. SUMMARY Some fishes mature and function as one sex aggressive behavior and sex in juveniles. I later demonstrated and later transform to the other sex in response to social that socially controlled sex determination does not typically interactions. Previous evidence suggested that a change in occur in the Midas cichlid and closely related species and developmental timing may be involved in the evolution of adult supported an alternative mechanism to explain large body sex change in fishes. The most recent support for this idea size in adult males. Finally, in the current study I analyze came from reports that sex in the Midas cichlid, Amphilophus gonad histology of fish from the same population used by the citrinellus, was determined by social conditions experienced at original authors and lay to rest the idea of socially controlled the juvenile stage. Differentiation as a male was reported to be sex determination in this species. Recent observations of dependent on large body size relative to group-mates, and socially controlled sex determination in juveniles of species thought to be mediated through aggressive interactions. Here that typically change sex at the adult stage are examples of I demonstrate that socially controlled sex determination does phenotypic plasticity, not genetic variation.
    [Show full text]