347 results on '"Friday Harbor Laboratories"'
Search Results
2. Simulating social-ecological systems: the Island Digital Ecosystem Avatars (IDEA) consortium
- Author
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Jennifer A. Dunne, Sally J. Holbrook, Mike Harfoot, Dawn Field, Hunter S. Lenihan, George K. Roderick, Georgios Kotoulas, Antoine Collin, Slava G. Turyshev, Serge Planes, Benoit Stoll, Billie J. Swalla, Tony Dell, Antonios Magoulas, Véronique Berteaux, Hervé Bossin, James J. Leichter, Hinano Teavai Murphy, Russell J. Schmitt, Fernanda Valdvinos, Neil M Davies, Spencer A. Wood, Patrick V. Kirch, Joachim Claudet, Alex Kosenkov, Daniel M. Tartakovsky, Matthias Troyer, David J. Gavaghan, Christopher P. Meyer, Ruth D. Gates, Neo D. Martinez, Rich Williams, Marania Hopuare, Linda A. Amaral Zettler, Michael B. Bonsall, Alex Kusenko, John Deck, James L. Hench, Charlotte Cabasse, Jacobs University [Bremen], Hawaii Pacific University, Departement of Computer of Science University of Oxford, University of Oxford [Oxford], Department of Ecology, Evolution and Marine Biology, University of California [Santa Barbara], Coastal Research Center, Marine Science Institute, Laboratoire d'Excellence CORAIL ( LabEX CORAIL ), Institut de Recherche pour le Développement ( IRD ) -Université des Antilles et de la Guyane ( UAG ) -École des hautes études en sciences sociales ( EHESS ) -École pratique des hautes études ( EPHE ) -Institut Français de Recherche pour l'Exploitation de la Mer ( IFREMER ) -Université de la Réunion ( UR ) -Université de la Polynésie Française ( UPF ) -Université de Nouvelle Calédonie-Institut d'écologie et environnement, Theoretische Physik, ETH Zurich, Eidgenössische Technische Hochschule [Zürich] ( ETH Zürich ), Department of zoology, Environmental Science Policy and Management (ESPM), University of California, Laboratoire Techniques, Territoires et Sociétés ( LATTS ), Université Paris-Est Marne-la-Vallée ( UPEM ) -École des Ponts ParisTech ( ENPC ) -Centre National de la Recherche Scientifique ( CNRS ), Berkeley natural history museums, University of California [Berkeley], NOAA Geophysical Fluid Dynamics Laboratory ( GFDL ), National Oceanic and Atmospheric Administration ( NOAA ), Hawai'i Institute of Marine Biology, IMBBC, HCMR, Hellenic Centre for Marine Research ( HCMR ) -Hellenic Centre for Marine Research ( HCMR ), Institute of Marine Biology and Genetics, Hellenic Center for Marine Research ( HCMR ), Institut Laue-Langevin ( ILL ), ILL, Laboratoire Chrono-environnement ( LCE ), Université Bourgogne Franche-Comté ( UBFC ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Franche-Comté ( UFC ), Institut für Geophysik und Extraterrestrische Physik [Braunschweig] ( IGEP ), Technische Universität Braunschweig [Braunschweig], Friday Harbor Laboratories, University of Washington [Seattle], Department of Mechanical and Aerospace Engineering [San Diego] ( UCSD ), University of California [San Diego] ( UC San Diego ), Laboratory of Molecular Genetics, National Institute of Child Health and Human Development, National Institutes of Health, Jet Propulsion Laboratory ( JPL ), NASA-California Institute of Technology ( CALTECH ), CSIRO Land and Water, Commonwealth Scientific and Industrial Research Organisation [Canberra] ( CSIRO ), National Centre for Adult Stem Cell Research, Griffith University, Department of Ecology, Evolution and Marine Biology [Santa Barbara] (EEMB), University of California [Santa Barbara] (UC Santa Barbara), University of California (UC)-University of California (UC), Laboratoire d'Excellence CORAIL (LabEX CORAIL), Institut de Recherche pour le Développement (IRD)-Université des Antilles et de la Guyane (UAG)-École des hautes études en sciences sociales (EHESS)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de La Réunion (UR)-Université de la Polynésie Française (UPF)-Université de la Nouvelle-Calédonie (UNC)-Institut d'écologie et environnement-Université des Antilles (UA), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), University of California (UC), Laboratoire Techniques, Territoires et Sociétés (LATTS), Université Paris-Est Marne-la-Vallée (UPEM)-École des Ponts ParisTech (ENPC)-Centre National de la Recherche Scientifique (CNRS), NOAA Geophysical Fluid Dynamics Laboratory (GFDL), National Oceanic and Atmospheric Administration (NOAA), Hawai'i Institute of Marine Biology (HIMB), Hellenic Centre for Marine Research (HCMR)-Hellenic Centre for Marine Research (HCMR), Hellenic Centre for Marine Research (HCMR), Institut Laue-Langevin (ILL), Institut für Geophysik und Extraterrestrische Physik [Braunschweig] (IGEP), Technische Universität Braunschweig = Technical University of Braunschweig [Braunschweig], Department of Mechanical and Aerospace Engineering [Univ California San Diego] (MAE - UC San Diego), University of California [San Diego] (UC San Diego), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Commonwealth Scientific and Industrial Research Organisation [Canberra] (CSIRO), Griffith University [Brisbane], University of California [Santa Barbara] (UCSB), University of California-University of California, Hellenic Center for Marine Research (HCMR), Department of Mechanical and Aerospace Engineering [La Jolla] (UCSD), California Institute of Technology (CALTECH)-NASA, Université des Antilles (UA)-Institut d'écologie et environnement-Université de la Nouvelle-Calédonie (UNC)-Université de la Polynésie Française (UPF)-Université de La Réunion (UR)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-École pratique des hautes études (EPHE), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École des hautes études en sciences sociales (EHESS)-Université des Antilles et de la Guyane (UAG)-Institut de Recherche pour le Développement (IRD)
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0301 basic medicine ,Open science ,010504 meteorology & atmospheric sciences ,Computational ecology ,Computer science ,Climate ,Biocode ,Ecological systems theory ,Ecosystem dynamics ,01 natural sciences ,Schema (psychology) ,Human Activities ,ComputingMilieux_MISCELLANEOUS ,Islands ,Ecology ,[SDE.IE]Environmental Sciences/Environmental Engineering ,Life Sciences ,Biodiversity ,Genomics ,Predictive modeling ,Computer Science Applications ,[ SDE.MCG ] Environmental Sciences/Global Changes ,Earth observations ,Social-ecological system ,Climate change scenarios ,Conservation of Natural Resources ,[SDE.MCG]Environmental Sciences/Global Changes ,Systems biology ,Health Informatics ,BioCode ,Polynesia ,[ SDE.IE ] Environmental Sciences/Environmental Engineering ,03 medical and health sciences ,Systems ecology ,Humans ,14. Life underwater ,Ecosystem ,0105 earth and related environmental sciences ,[ SDE.BE ] Environmental Sciences/Biodiversity and Ecology ,Davies [BRII recipient] ,Models, Theoretical ,[SDE.ES]Environmental Sciences/Environmental and Society ,Data science ,Digital ecosystem ,030104 developmental biology ,13. Climate action ,Sustainability ,Commentary ,[SDE.BE]Environmental Sciences/Biodiversity and Ecology ,[ SDE.ES ] Environmental Sciences/Environmental and Society ,Forecasting - Abstract
Systems biology promises to revolutionize medicine, yet human wellbeing is also inherently linked to healthy societies and environments (sustainability). The IDEA Consortium is a systems ecology open science initiative to conduct the basic scientific research needed to build use-oriented simulations (avatars) of entire social-ecological systems. Islands are the most scientifically tractable places for these studies and we begin with one of the best known: Moorea, French Polynesia. The Moorea IDEA will be a sustainability simulator modeling links and feedbacks between climate, environment, biodiversity, and human activities across a coupled marine–terrestrial landscape. As a model system, the resulting knowledge and tools will improve our ability to predict human and natural change on Moorea and elsewhere at scales relevant to management/conservation actions., GigaScience, 5 (1), ISSN:2047-217X
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- 2016
3. Managing marine disease emergencies in an era of rapid change
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Maya L. Groner, Ryan B. Carnegie, Sandy Wyllie-Echeverria, Jeffrey D. Shields, Melissa Garren, Crawford W. Revie, Ernesto Weil, Rachel T. Noble, Andrew P. Dobson, Frances M. D. Gulland, Jeffrey Maynard, Brett Froelich, C. Drew Harvell, Scott F. Heron, Carolyn S. Friedman, Raphaël Vanderstichel, Rachel Breyta, Centre for Veterinary Epidemiological Research, University of Prince Edward Island, Department of Ecology & Evolutionary Biology, University of California, Laboratoire d'Excellence CORAIL (LabEX CORAIL), Institut de Recherche pour le Développement (IRD)-Université des Antilles et de la Guyane (UAG)-École des hautes études en sciences sociales (EHESS)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de La Réunion (UR)-Université de la Polynésie Française (UPF)-Université de la Nouvelle-Calédonie (UNC)-Institut d'écologie et environnement-Université des Antilles (UA), Centre de recherches insulaires et observatoire de l'environnement (CRIOBE), Université de Perpignan Via Domitia (UPVD)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), School of Aquatic and Fishery Sciences, University of Washington [Seattle], Virginia Institute of Marine Science (VIMS), Department of Ecology and Evolutionary Biology [Princeton], Princeton University, Institute of Marine Sciences, University of North Carolina [Chapel Hill] (UNC), University of North Carolina System (UNC)-University of North Carolina System (UNC), Department of Science and Environmental Policy [Monterey Bay], California State University [Monterey Bay] (CSUMB), The Marine Mammal Center, Coral Reef Watch, NOAA Center for Satellite Applications and Research (STAR), NOAA National Environmental Satellite, Data, and Information Service (NESDIS), National Oceanic and Atmospheric Administration (NOAA)-National Oceanic and Atmospheric Administration (NOAA)-NOAA National Environmental Satellite, Data, and Information Service (NESDIS), National Oceanic and Atmospheric Administration (NOAA)-National Oceanic and Atmospheric Administration (NOAA), Marine Geophysical Laboratory, James Cook University (JCU), Department of Marine Sciences, University of Puerto Rico (UPR), Center for Marine and Environmental Studies (CMES), University of the Virgin Islands (UVI), Friday Harbor Laboratories, Department of Ecology and Evolutionary Biology, and Cornell University [New York]
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0106 biological sciences ,0301 basic medicine ,Conservation of Natural Resources ,adaptive management ,marine disease ,response plan ,Disease ,01 natural sciences ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,environmental law ,Animals ,14. Life underwater ,Resilience (network) ,[SDV.EE]Life Sciences [q-bio]/Ecology, environment ,Disease surveillance ,Transmission (medicine) ,business.industry ,010604 marine biology & hydrobiology ,Environmental resource management ,Articles ,impact mitigation ,Environmental law ,Adaptive management ,030104 developmental biology ,13. Climate action ,Mollusca ,Host-Pathogen Interactions ,Disease risk ,surveillance ,Emergencies ,General Agricultural and Biological Sciences ,business ,Impact mitigation ,Environmental Monitoring - Abstract
International audience; Infectious marine diseases can decimate populations and are increasing among some taxa due to global change and our increasing reliance on marine environments. Marine diseases become emergencies when significant ecological, economic or social impacts occur. We can prepare for and manage these emergencies through improved surveillance, and the development and iterative refinement of approaches to mitigate disease and its impacts. Improving surveillance requires fast, accurate diagnoses, forecasting disease risk and real-time monitoring of disease-promoting environmental conditions. Diversifying impact mitigation involves increasing host resilience to disease, reducing pathogen abundance and managing environmental factors that facilitate disease. Disease surveillance and mitigation can be adaptive if informed by research advances and catalysed by communication among observers, researchers and decision-makers using information-sharing platforms. Recent increases in the awareness of the threats posed by marine diseases may lead to policy frameworks that facilitate the responses and management that marine disease emergencies require.
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- 2016
4. ANISEED 2015: a digital framework for the comparative developmental biology of ascidians
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Brozovic, Matija, Martin, Cyril, Dantec, Christelle, Dauga, Delphine, Mendez, Mickäel, Simion, Paul, Percher, Madeline, Laporte, Baptiste, Scornavacca, Celine, Di Gregorio, Anna, Fujiwara, Shigeki, Gineste, Mathieu, Lowe, Elijah K., Piette, Jacques, Racioppi, Claudia, Ristoratore, Filomena, Sasakura, Yasunori, Takatori, Naohito, Brown, Titus C., Delsuc, Fréderic, Douzery, Emmanuel, Gissi, Carmela, Mcdougall, Alex, Nishida, Hiroki, Sawada, Hitoshi, Swalla, Billie J., Yasuo, Hitoyoshi, Lemaire, Patrick, HAL UPMC, Gestionnaire, Centre de recherche en Biologie cellulaire de Montpellier (CRBM), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Institut de Biologie du Développement de Marseille (IBDM), Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Centre National de la Recherche Scientifique (CNRS), Bioself Communication [Marseille], Institut des Sciences de l'Evolution de Montpellier (UMR ISEM), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Institut de recherche pour le développement [IRD] : UR226-Centre National de la Recherche Scientifique (CNRS), New York University College of Dentistry, NYU System (NYU), Kochi University, Stazione Zoologica Anton Dohrn (SZN), Michigan State University [East Lansing], Michigan State University System, New York University [New York] (NYU), Shimoda Marine Research Center, Université de Tsukuba = University of Tsukuba, Osaka University [Osaka], Tokyo Metropolitan University [Tokyo] (TMU), University of California [Davis] (UC Davis), University of California (UC), Università degli Studi di Milano = University of Milan (UNIMI), Laboratoire de Biologie du Développement de Villefranche sur mer (LBDV), Observatoire océanologique de Villefranche-sur-mer (OOVM), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Nagoya (NAGOYA), Nagoya University, Friday Harbor Laboratories, University of Washington [Seattle], Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-École Pratique des Hautes Études (EPHE), Centre de recherche en Biologie Cellulaire (CRBM), Université Montpellier 2 - Sciences et Techniques (UM2)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1), University of California, Università degli Studi di Milano [Milano] (UNIMI), and Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)
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[SDV]Life Sciences [q-bio] ,Human Genome ,Embryonic Development ,Bioengineering ,Genomics ,Biological Sciences ,Regenerative Medicine ,Stem Cell Research ,Ciona intestinalis ,[SDV] Life Sciences [q-bio] ,Databases ,Genetic ,Information and Computing Sciences ,Databases, Genetic ,Genetics ,Database Issue ,Animals ,Generic health relevance ,Urochordata ,Environmental Sciences ,Biotechnology ,Developmental Biology - Abstract
Ascidians belong to the tunicates, the sister group of vertebrates and are recognized model organisms in the field of embryonic development, regeneration and stem cells. ANISEED is the main information system in the field of ascidian developmental biology. This article reports the development of the system since its initial publication in 2010. Over the past five years, we refactored the system from an initial custom schema to an extended version of the Chado schema and redesigned all user and back end interfaces. This new architecture was used to improve and enrich the description of Ciona intestinalis embryonic development, based on an improved genome assembly and gene model set, refined functional gene annotation, and anatomical ontologies, and a new collection of full ORF cDNAs. The genomes of nine ascidian species have been sequenced since the release of the C. intestinalis genome. In ANISEED 2015, all nine new ascidian species can be explored via dedicated genome browsers, and searched by Blast. In addition, ANISEED provides full functional gene annotation, anatomical ontologies and some gene expression data for the six species with highest quality genomes. ANISEED is publicly available at: http://www.aniseed.cnrs.fr.
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- 2016
5. Guidelines for the Nomenclature of Genetic Elements in Tunicate Genomes
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Stolfi, Alberto, Sasakura, Yasunori, Chalopin, Domitille, Satou, Yutaka, Christiaen, Lionel, Dantec, Christelle, Endo, Toshinori, Naville, Magali, Nishida, Hiroki, Swalla, Billie J., Volff, Jean-Nicolas, Voskoboynik, Ayelet, Dauga, Delphine, Lemaire, Patrick, Shimoda Marine Research Center, University of Tsukuba, École normale supérieure - Lyon (ENS Lyon), Institut de Génomique Fonctionnelle de Lyon (IGFL), École normale supérieure - Lyon (ENS Lyon)-Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Kyoto University [Kyoto], Department of Molecular & Cell Biology [Berkeley], University of California [Berkeley], University of California-University of California, Centre de recherche en Biologie Cellulaire (CRBM), Université Montpellier 1 (UM1)-Université Montpellier 2 - Sciences et Techniques (UM2)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Institut de biologie de l'ENS Paris (UMR 8197/1024) (IBENS), Département de Biologie - ENS Paris, École normale supérieure - Paris (ENS Paris)-École normale supérieure - Paris (ENS Paris)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Osaka University [Osaka], Friday Harbor Laboratories, University of Washington [Seattle], HOPKINS MARINE STATION, Stanford University [Stanford], Bioself Communication [Marseille], Université de Tsukuba = University of Tsukuba, École normale supérieure de Lyon (ENS de Lyon), École normale supérieure de Lyon (ENS de Lyon)-Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL), Kyoto University, University of California [Berkeley] (UC Berkeley), University of California (UC)-University of California (UC), Centre de recherche en Biologie cellulaire de Montpellier (CRBM), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Institut de biologie de l'ENS Paris (IBENS), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Hopkins Marine Station [Stanford], Stanford University, National Science Foundation Postdoctoral Research Fellowship in Biology NSF-1161835 National Bioresource Project (Japan) NIGMS/NIH R01GM096032 NHLBI/NIH R01HL108643 R01GM100315 1R01AG037968 PIME from CNRS National Science Foundation DBI-0939454, Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA)-École normale supérieure - Lyon (ENS Lyon), Université Montpellier 2 - Sciences et Techniques (UM2)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Université Montpellier 1 (UM1), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Département de Biologie - ENS Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)
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EXPRESSION ,Transcription, Genetic ,genome annotation ,DATABASE ,tunicates ,Guidelines as Topic ,SEQUENCE ,Article ,cis-regulatory sequences ,Terminology as Topic ,LHX3 ,Genes, Overlapping ,Animals ,Urochordata ,PLASTICITY ,gene ,Phylogeny ,Genome ,Chromosome Mapping ,Genomics ,transposable element ,CHORDATE ,ASCIDIAN CIONA-INTESTINALIS ,Antisense Elements (Genetics) ,Genetic Loci ,[SCCO.PSYC]Cognitive science/Psychology ,SYSTEM - Abstract
International audience; Tunicates are invertebrate members of the chordate phylum, and are considered to be the sister group of vertebrates. Tunicates are composed of ascidians, thaliaceans, and appendicularians. With the advent of inexpensive high-throughput sequencing, the number of sequenced tunicate genomes is expected to rise sharply within the coming years. To facilitate comparative genomics within the tunicates, and between tunicates and vertebrates, standardized rules for the nomenclature of tunicate genetic elements need to be established. Here we propose a set of nomenclature rules, consensual within the community, for predicted genes, pseudogenes, transcripts, operons, transcriptional cis-regulatory regions, transposable elements, and transgenic constructs. In addition, the document proposes guidelines for naming transgenic and mutant lines. genesis 53:65-78, 2015. (c) 2014 Wiley Periodicals, Inc.
- Published
- 2015
6. Regeneration and Stem Cells in Ascidians
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Anthony W. De Tomaso, Federico D. Brown, Stefano Tiozzo, Stanford University, Hopkins Marine Station [Stanford], University of Washington [Seattle], and Friday Harbor Laboratories
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0303 health sciences ,media_common.quotation_subject ,fungi ,Zoology ,Chordate ,Biology ,biology.organism_classification ,Regenerative medicine ,3. Good health ,03 medical and health sciences ,0302 clinical medicine ,Body plan ,medicine.anatomical_structure ,Notochord ,medicine ,Lernaean Hydra ,14. Life underwater ,Metamorphosis ,Stem cell ,Developmental biology ,[SDV.BDD]Life Sciences [q-bio]/Development Biology ,030217 neurology & neurosurgery ,030304 developmental biology ,media_common - Abstract
Understanding and utilizing the ability of stem cells to expand and differentiate into tissues and organs is a major goal of biomedical science. Ascidians are basal chordates (Tunicata) which offer unique opportunities to investigate the biology of stem cells. These marine organisms begin their life as a larva with a typical chordate body plan, including a notochord, dorsal hollow nerve tube and a striated musculature. After a swimming phase, the larvae settles and undergoes an extensive metamorphosis during which most of the chordate characteristics are resorbed, leaving a filter feeding sessile invertebrate adult. Due to its small size (in many species a larva consists of ca. 2,500 cells) and rapid development (a fertilized egg can complete development in less that 24 h in Ciona species), the study of ascidian larvae has a long history and continues to be an outstanding model for studying specification and differentiation events which occur during chordate embryogenesis. In comparison, the adult body plan is relatively unstudied at a molecular level, but several examples of extensive regeneration following surgical ablation of different tissues have been described. In addition, within this chordate subphylum two distinct adult body plans exist: solitary and colonial. Following larval metamorphosis, solitary species grow into an adult that can range from several millimeters to tens of centimeters in length. In addition, colonial species grow not by increasing in size, but by asexually propagating, eventually creating a colony of genetically identical individuals that can cover areas of several square meters. 1 Institute for Stem Cell Biology and Regenerative Medicine, Stanford University, Stanford, CA 94305, USA 2 Biology Department, Center for Developmental Biology and Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA 98195, USA 3 Friday Harbor Laboratories, University of Washington, Friday Harbor, WA 98250, USA 4 Department of Biological Sciences, Stanford University, Hopkins Marine Station, 120 Oceanview Blvd, Pacific Grove, CA 93950, USA * Author for correspondence Tel.: 831 655 6206, Fax: 831 3750793 E-mail: tdet@stanford.edu T.C.G. Bosch (ed.), Stem Cells: From Hydra to Man, 95 © Springer Science + Business Media B.V. 2008
- Published
- 2008
7. Atlas of pacific sand lance (Ammodytes personatus) benthic habitat - Application of multibeam acoustics and directed sampling to identify viable subtidal substrates.
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Baker MR, Greene HG, Aschoff J, Aitoro E, Bates E, Hesselroth D, Johnson K, Mather B, and Sealover N
- Abstract
Defining and delineating species distribution and habitat is critical to informed management and conservation. This process is complicated in marine environments, where detection of marine taxa and characterization of marine habitat is more difficult. Small pelagic fishes and forage fishes are particularly challenging, though insights may be more accessible in species highly dependent on particular habitat. Pacific sand lance (Ammodytes personatus) is a common and ecologically-important pelagic fish that relies on specific benthic sediments for rest and refuge from predation. We applied multibeam echosounder (MBES) bathymetric data to develop high-definition benthic habitat maps and implemented multiyear sampling to assess potential habitat for sand lance via in situ sampling of sediments. We also applied acoustic Doppler current profilers (ADCP) data and tidally-driven volume-based ocean models to measure current strength and to visualize currents. We leveraged this data to further define and describe habitat for this important forage species. Sediment transport processes were mapped and areas of dispersal, embedment, and accumulation were evaluated. Dynamic bedform habitats, banner banks and glacial banks were identified as potential habitat and sampled for fish presence, density and sediment composition. In the central Salish Sea, approximately 25% of benthic substrates represent potential sand lance habitat. Sand lance prevalence and density correlated with substrate type and sediment coarseness. Densities were highest in areas of coarse grain sediments and presence was limited by fine particulates, such as silt and mud. Tidal currents appear important. Presence and densities of sand lance were correlated with current velocity and distance from current flow path. Nearly all viable sites were located on the immediate margins of high flow (<0.16 km from tidal currents with max speed of 1.72-2.58 m/s). While both flood and ebb were important, processes related to flood were dominant. Viable habitat was not constrained by depth. These results inform a developing atlas for sand lance in the central Salish Sea, provide new insights to subtidal sand lance habitat, characterize conditions that create and maintain subtidal benthic habitat, and provide a template for mapping habitat for this species in the coastal Pacific Ocean., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)
- Published
- 2024
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8. Cytokinetic contractile ring structural progression in an early embryo: positioning of scaffolding proteins, recruitment of α-actinin, and effects of myosin II inhibition.
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Henson JH, Reyes G, Lo NT, Herrera K, McKim QW, Herzon HY, Galvez-Ceron M, Hershey AE, Kim RS, and Shuster CB
- Abstract
Our knowledge of the assembly and dynamics of the cytokinetic contractile ring (CR) in animal cells remains incomplete. We have previously used super-resolution light microscopy and platinum replica electron microscopy to elucidate the ultrastructural organization of the CR in first division sea urchin embryos. To date, our studies indicate that the CR initiates as an equatorial band of clusters containing myosin II, actin, septin and anillin, which then congress over time into patches which coalesce into a linear array characteristic of mature CRs. In the present study, we applied super-resolution interferometric photoactivated localization microscopy to confirm the existence of septin filament-like structures in the developing CR, demonstrate the close associations between septin2, anillin, and myosin II in the CR, as well as to show that septin2 appears consistently submembranous, whereas anillin is more widely distributed in the early CR. We also provide evidence that the major actin cross-linking protein α-actinin only associates with the linearized, late-stage CR and not with the early CR clusters, providing further support to the idea that α-actinin associates with actomyosin structures under tension and can serve as a counterbalance. In addition, we show that inhibition of actomyosin contraction does not stop the assembly of the early CR clusters but does arrest the progression of these structures to the aligned arrays required for functional cytokinesis. Taken together our results reinforce and extend our model for a cluster to patch to linear structural progression of the CR in sea urchin embryos and highlight the evolutionary relationships with cytokinesis in fission yeast., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Henson, Reyes, Lo, Herrera, McKim, Herzon, Galvez-Ceron, Hershey, Kim and Shuster.)
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- 2024
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9. Repeated Hyposalinity Pulses Immediately and Persistently Impair the Sea Urchin Adhesive System.
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Garner AM, Moura AJ, Narvaez CA, Stark AY, and Russell MP
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- Animals, Strongylocentrotus physiology, Adhesiveness, Climate Change, Sea Urchins physiology, Salinity, Locomotion physiology
- Abstract
Climate change will increase the frequency and intensity of extreme climatic events (e.g., storms) that result in repeated pulses of hyposalinity in nearshore ecosystems. Sea urchins inhabit these ecosystems and are stenohaline (restricted to salinity levels ∼32‰), thus are particularly susceptible to hyposalinity events. As key benthic omnivores, sea urchins use hydrostatic adhesive tube feet for numerous functions, including attachment to and locomotion on the substratum as they graze for food. Hyposalinity severely impacts sea urchin locomotor and adhesive performance but several ecologically relevant and climate change-related questions remain. First, do sea urchin locomotion and adhesion acclimate to repeated pulses of hyposalinity? Second, how do tube feet respond to tensile forces during single and repeated hyposalinity events? Third, do the negative effects of hyposalinity exposure persist following a return to normal salinity levels? To answer these questions, we repeatedly exposed green sea urchins (Strongylocentrotus droebachiensis) to pulses of three different salinities (control: 32‰, moderate hyposalinity: 22‰, severe hyposalinity: 16‰) over the course of two months and measured locomotor performance, adhesive performance, and tube foot tensile behavior. We also measured these parameters 20 h after sea urchins returned to normal salinity levels. We found no evidence that tube feet performance and properties acclimate to repeated pulses of hyposalinity, at least over the timescale examined in this study. In contrast, hyposalinity has severe consequences on locomotion, adhesion, and tube foot tensile behavior, and these impacts are not limited to the hyposalinity exposure. Our results suggest both moderate and severe hyposalinity events have the potential to increase sea urchin dislodgment and reduce movement, which may impact sea urchin distribution and their role in marine communities., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology.)
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- 2024
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10. Introduction to the 2024 Chordate Origins, Evolution and Development SICB Symposium.
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Swalla BJ
- Abstract
The evolution of the distinct chordate body plan has intrigued scientists for over a hundred and seventy years. Modern genomics and transcriptomics have allowed the elucidation of the Developmental Gene Regulatory Networks (GRNs) underlying the developmental programs for particular tissues and body axes in invertebrates and vertebrates. This has been most revealing in the Deuterostomia, the superphylum in which chordates evolved. The time was ripe to gather those working on deuterostome developmental GRNs to revisit the development and evolution of chordates and discuss the evolution of this unique body plan at the SICB 2024 meetings in Seattle, WA. It has been several years since the genomes of the major deuterostome clades have been sequenced - echinoderms, hemichordates, tunicates, lancelets and vertebrates. Genomic analyses have shown that lancelets have a genome and body plan that closely resemble the vertebrates, although phylogenomic analyses suggest that the tunicates are the sister group of the vertebrates. The evolution of the sessile and sometimes colonial adult tunicates was likely from a motile, lancelet-like ancestor. Scientists from all over the world converged at the SICB meetings in Seattle to discuss the current ideas of how chordates evolved. Some common mechanisms and themes emerged and are captured in this ICB volume on Chordate Origins, Evolution and Development., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology.)
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- 2024
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11. Deuterostome Ancestors and Chordate Origins.
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Swalla BJ
- Abstract
The Deuterostomia are a monophyletic group, consisting of the Ambulacraria, with two phyla, Hemichordata and Echinodermata, and the phylum Chordata, containing the subphyla Cephalochordata (lancelets or Amphioxus), Tunicata (Urochordata) and Vertebrata. Hemichordates and echinoderms are sister groups and are critical for understanding the deuterostome ancestor and the origin and evolution of the chordates within the deuterostomes. Enteropneusta, worm-like hemichordates, share many chordate features as adults, including a post-anal tail, gill slits, and a Central Nervous System (CNS) that deploy similar developmental Genetic Regulatory Networks (GRNs). Genomic comparisons show that cephalochordates share synteny and a vermiform body plan similar to vertebrates, but phylogenomic analyses place tunicates as the sister group of vertebrates. Tunicates have a U-shaped gut and a very different adult body plan than the rest of the chordates, and all tunicates have small genomes and many gene losses, although the GRNs underlying specific tissues, such as notochord and muscle, are conserved. Echinoderms and vertebrates have extensive fossil records, with fewer specimens found for tunicates and enteropneusts, or worm-like hemichordates. The data is mounting that the deuterostome ancestor was a complex benthic worm, with gill slits, a cartilaginous skeleton, and a CNS. Two extant groups, echinoderms and tunicates, have evolved highly derived body plans, remarkably different than the deuterostome ancestor. We review the current genomic and GRN data on the different groups of deuterostomes' characters to re-evaluate different hypotheses of chordate origins. Notochord loss in echinoderms and hemichordates is as parsimonious as notochord gain in the chordates but has implications for the deuterostome ancestor. The chordate ancestor lost an ancestral nerve net, retained the central nervous system, and evolved neural crest cells., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology.)
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- 2024
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12. STEERING FROM THE REAR: COORDINATION OF CENTRAL PATTERN GENERATORS UNDERLYING NAVIGATION BY ASCENDING INTERNEURONS.
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Jonaitis J, Hibbard KL, McCafferty Layte K, Hiramoto A, Cardona A, Truman JW, Nose A, Zwart MF, and Pulver SR
- Abstract
Understanding how animals coordinate movements to achieve goals is a fundamental pursuit in neuroscience. Here we explore how neurons that reside in posterior lower-order regions of a locomotor system project to anterior higher-order regions to influence steering and navigation. We characterized the anatomy and functional role of a population of ascending interneurons in the ventral nerve cord of Drosophila larvae. Through electron microscopy reconstructions and light microscopy, we determined that the cholinergic 19f cells receive input primarily from premotor interneurons and synapse upon a diverse array of postsynaptic targets within the anterior segments including other 19f cells. Calcium imaging of 19f activity in isolated central nervous system (CNS) preparations in relation to motor neurons revealed that 19f neurons are recruited into most larval motor programmes. 19f activity lags behind motor neuron activity and as a population, the cells encode spatio-temporal patterns of locomotor activity in the larval CNS. Optogenetic manipulations of 19f cell activity in isolated CNS preparations revealed that they coordinate the activity of central pattern generators underlying exploratory headsweeps and forward locomotion in a context and location specific manner. In behaving animals, activating 19f cells suppressed exploratory headsweeps and slowed forward locomotion, while inhibition of 19f activity potentiated headsweeps, slowing forward movement. Inhibiting activity in 19f cells ultimately affected the ability of larvae to remain in the vicinity of an odor source during an olfactory navigation task. Overall, our findings provide insights into how ascending interneurons monitor motor activity and shape interactions amongst rhythm generators underlying complex navigational tasks.
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- 2024
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13. The embryonic role of juvenile hormone in the firebrat, Thermobia domestica, reveals its function before its involvement in metamorphosis.
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Truman JW, Riddiford LM, Konopova B, Nouzova M, Noriega FG, and Herko M
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- Animals, Insecta, Morphogenesis, Juvenile Hormones, Metamorphosis, Biological physiology
- Abstract
To gain insights into how juvenile hormone (JH) came to regulate insect metamorphosis, we studied its function in the ametabolous firebrat, Thermobia domestica . Highest levels of JH occur during late embryogenesis, with only low levels thereafter. Loss-of-function and gain-of-function experiments show that JH acts on embryonic tissues to suppress morphogenesis and cell determination and to promote their terminal differentiation. Similar embryonic actions of JH on hemimetabolous insects with short germ band embryos indicate that JH's embryonic role preceded its derived function as the postembryonic regulator of metamorphosis. The postembryonic expansion of JH function likely followed the evolution of flight. Archaic flying insects were considered to lack metamorphosis because tiny, movable wings were evident on the thoraces of young juveniles and their positive allometric growth eventually allowed them to support flight in late juveniles. Like in Thermobia , we assume that these juveniles lacked JH. However, a postembryonic reappearance of JH during wing morphogenesis in the young juvenile likely redirected wing development to make a wing pad rather than a wing. Maintenance of JH then allowed wing pad growth and its disappearance in the mature juvenile then allowed wing differentiation. Subsequent modification of JH action for hemi- and holometabolous lifestyles are discussed., Competing Interests: JT, LR, BK, MN, FN, MH No competing interests declared, (© 2023, Truman et al.)
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- 2024
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14. Ordovician origin and subsequent diversification of the brown algae.
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Choi SW, Graf L, Choi JW, Jo J, Boo GH, Kawai H, Choi CG, Xiao S, Knoll AH, Andersen RA, and Yoon HS
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- Phylogeny, Eukaryota genetics, Plants, Plastids genetics, Evolution, Molecular, Rhodophyta genetics, Phaeophyceae genetics
- Abstract
Brown algae are the only group of heterokont protists exhibiting complex multicellularity. Since their origin, brown algae have adapted to various marine habitats, evolving diverse thallus morphologies and gamete types. However, the evolutionary processes behind these transitions remain unclear due to a lack of a robust phylogenetic framework and problems with time estimation. To address these issues, we employed plastid genome data from 138 species, including heterokont algae, red algae, and other red-derived algae. Based on a robust phylogeny and new interpretations of algal fossils, we estimated the geological times for brown algal origin and diversification. The results reveal that brown algae first evolved true multicellularity, with plasmodesmata and reproductive cell differentiation, during the late Ordovician Period (ca. 450 Ma), coinciding with a major diversification of marine fauna (the Great Ordovician Biodiversification Event) and a proliferation of multicellular green algae. Despite its early Paleozoic origin, the diversification of major orders within this brown algal clade accelerated only during the Mesozoic Era, coincident with both Pangea rifting and the diversification of other heterokont algae (e.g., diatoms), coccolithophores, and dinoflagellates, with their red algal-derived plastids. The transition from ancestral isogamy to oogamy was followed by three simultaneous reappearances of isogamy during the Cretaceous Period. These are concordant with a positive character correlation between parthenogenesis and isogamy. Our new brown algal timeline, combined with a knowledge of past environmental conditions, shed new light on brown algal diversification and the intertwined evolution of multicellularity and sexual reproduction., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)
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- 2024
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15. Complete chloroplast genome of the marine red alga Rhodochorton tenue (Rhodochortonaceae, Rhodophyta) from San Juan Island, Washington.
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Ahmed LT, Alesmail H, Beltran Rodriguez S, Christian R, Coronado J, Elledge AA, Estrada A, Fierro A, Garcia Mora A, Gonzalez K, Gonzalez-Leon S, Guijarro AM, Islas-Quintana J, Juarez-Guido D, Hughey JR, Lara EJ, Lara J, Leonard CT, Lockard KA, Lopez E, Martin S, Martinez M, Mederos B, Medina Pizano A, Medley CJ, Mohsin S, Mumford TF, Muñoz RA, Nachtigall R, Noriega J, Ochoa Cendejas P, Ordaz J, Parra AJ, Pizano J, Reimold M, Rivera K, Rocha A, Rodriguez KC, Tena-Garcia I, Vargas MM, and Velasquez J
- Abstract
We present the complete chloroplast genome sequence of Rhodochorton tenue from San Juan Island, Washington. The chloroplast genome of R. tenue is 192,037 bp in length, contains 244 genes, and is similar in content to Acrochaetium secundatum. Rhodochorton tenue is genetically distinct from Rhodochorton purpureum from the North Atlantic Ocean., Competing Interests: The authors declare no conflict of interest.
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- 2024
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16. A peripheral subepithelial network for chemotactile processing in the predatory sea slug Pleurobranchaea californica.
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Norekian T, Liu Y, Gribkova ED, Cui J, and Gillette R
- Subjects
- Animals, Peripheral Nervous System, Neurons, Aplysia, Predatory Behavior, Pleurobranchaea
- Abstract
Many soft-bodied animals have extensive peripheral nervous systems (PNS) with significant sensory roles. One such, the sea slug Pleurobranchaea californica, uses PNS computations in its chemotactile oral veil (OV) in prey tracking, averaging olfactory stimuli across the OV to target likely source direction, or "stimulus place". This suggests a peripheral subepithelial network (SeN) interconnecting sensory sites to compute the directional average. We pursued anatomy and connectivity of previously described ciliated putative sensory cells on OV papillae. Scanning electron microscopy (SEM) confirmed paddle-shaped cilia in clusters. Anti-tubulin and phalloidin staining showed connections to branching nervelets and muscle fibers for contraction and expansion of papillae. Ciliary cell processes could not be traced into nerves, consistent with sensory transmission to CNS via secondary afferents. Anti-tyrosine hydroxylase-stained ciliated cells in clusters and revealed an at least partially dopaminergic subepithelial network interconnecting clusters near and distant, connections consistent with PNS averaging of multiple stimulated loci. Other, unidentified, SeN neurotransmitters are likely. Confirming chemotactile functions, perfusible suction electrodes recorded ciliary spiking excited by both mechanical and appetitive chemical stimuli. Stimuli induced sensory nerve spiking like that encoding stimulus place. Sensory nerve spikes and cilia cluster spikes were not identifiable as generated by the same neurons. Ciliary clusters likely drive the sensory nerve spikes via SeN, mediating appetitive and stimulus place codes to CNS. These observations may facilitate future analyses of the PNS in odor discrimination and memory, and also suggest such SeNs as potential evolutionary precursors of CNS place-coding circuitry in the segmented, skeletonized protostomes and deuterostomes., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Norekian et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
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- 2024
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17. White shark comparison reveals a slender body for the extinct megatooth shark, Otodus megalodon (Lamniformes: Otodontidae).
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Sternes PC, Jambura PL, Türtscher J, Kriwet J, Siversson M, Feichtinger I, Naylor GJP, Summers AP, Maisey JG, Tomita T, Moyer JK, Higham TE, da Silva JPCB, Bornatowski H, Long DJ, Perez VJ, Collareta A, Underwood C, Ward DJ, Vullo R, González-Barba G, Maisch HM, Griffiths ML, Becker MA, Wood JJ, and Shimada K
- Abstract
The megatooth shark, † Otodus megalodon , which likely reached at least 15 m in total length, is an iconic extinct shark represented primarily by its gigantic teeth in the Neogene fossil record. As one of the largest marine carnivores to ever exist, understanding the biology, evolution, and extinction of † O. megalodon is important because it had a significant impact on the ecology and evolution of marine ecosystems that shaped the present-day oceans. Some attempts inferring the body form of † O. megalodon have been carried out, but they are all speculative due to the lack of any complete skeleton. Here we highlight the fact that the previous total body length estimated from vertebral diameters of the extant white shark (Carcharodon carcharias) for an † O. megalodon individual represented by an incomplete vertebral column is much shorter than the sum of anteroposterior lengths of those fossil vertebrae. This factual evidence indicates that † O. megalodon had an elongated body relative to the body of the modern white shark. Although its exact body form remains unknown, this proposition represents the most parsimonious empirical evidence, which is a significant step towards deciphering the body form of † O. megalodon .
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- 2024
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18. Influence of marine habitat on microplastic prevalence in forage fish and salmon in the Salish Sea.
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Selden KR and Baker MR
- Subjects
- Animals, Humans, Microplastics, Salmon, Plastics analysis, Ecosystem, Prevalence, Fishes, Environmental Monitoring, Oncorhynchus, Perciformes, Water Pollutants, Chemical analysis
- Abstract
Microplastics are increasingly prevalent in marine systems and are a growing concern as a marine pollutant and contaminant with consequences for high trophic level consumers, including humans. Given evidence that links plastics to degraded ecosystem functioning and organismal health, there is increased interest in understanding the prevalence, fate and consequences of marine plastics. Microplastics contain and absorb harmful chemicals which may serve as endocrine disruptors and have negative implications for growth, reproductive health, and longevity. To expand current knowledge on microplastics in coastal marine ecosystems and the potential for biomagnification in marine food webs, we conducted stomach analyses of microplastics in Pacific salmon (Oncorhynchus spp.) and Pacific sand lance (Ammodytes personatus), an important prey for salmon. Prevalence of microplastics was substantial; 77 % of all salmon and 25 % of all sand lance stomachs contained at least one microplastic. Fish were sampled at multiple sites throughout the inland Salish Sea, including beaches and sediment bedforms for Pacific sand lance and open-water pelagic habitat for Pacific salmon. Pacific sand lance sampled at beach sites had more microplastics compared to those sampled in subtidal sediments and there were more plastics in sand lance at a protected beach site as compared to an exposed beach site. Prevalence of plastics in salmon differed according to species and included analyses of pink salmon (Oncorhynchus gorbuscha), Chinook (Oncorhynchus tshawytscha), and Coho salmon (Oncorhynchus kisutch); plastics were predominantly fibers in all species, though there were relatively higher rates of ingestion of films and particles in Chinook. Comparisons between plastic concentrations and stomach fullness indicated a slight negative trend, suggesting that plastics may be retained. Further investigation is needed to develop a more thorough understanding of the prevalence and fate of microplastics in coastal marine systems such as the Salish Sea, their concentration within marine food webs, and the implications for species targeted in fisheries., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)
- Published
- 2023
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19. Specimen collection is essential for modern science.
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Nachman MW, Beckman EJ, Bowie RC, Cicero C, Conroy CJ, Dudley R, Hayes TB, Koo MS, Lacey EA, Martin CH, McGuire JA, Patton JL, Spencer CL, Tarvin RD, Wake MH, Wang IJ, Achmadi A, Álvarez-Castañeda ST, Andersen MJ, Arroyave J, Austin CC, Barker FK, Barrow LN, Barrowclough GF, Bates J, Bauer AM, Bell KC, Bell RC, Bronson AW, Brown RM, Burbrink FT, Burns KJ, Cadena CD, Cannatella DC, Castoe TA, Chakrabarty P, Colella JP, Cook JA, Cracraft JL, Davis DR, Davis Rabosky AR, D'Elía G, Dumbacher JP, Dunnum JL, Edwards SV, Esselstyn JA, Faivovich J, Fjeldså J, Flores-Villela OA, Ford K, Fuchs J, Fujita MK, Good JM, Greenbaum E, Greene HW, Hackett S, Hamidy A, Hanken J, Haryoko T, Hawkins MT, Heaney LR, Hillis DM, Hollingsworth BD, Hornsby AD, Hosner PA, Irham M, Jansa S, Jiménez RA, Joseph L, Kirchman JJ, LaDuc TJ, Leaché AD, Lessa EP, López-Fernández H, Mason NA, McCormack JE, McMahan CD, Moyle RG, Ojeda RA, Olson LE, Kin Onn C, Parenti LR, Parra-Olea G, Patterson BD, Pauly GB, Pavan SE, Peterson AT, Poe S, Rabosky DL, Raxworthy CJ, Reddy S, Rico-Guevara A, Riyanto A, Rocha LA, Ron SR, Rovito SM, Rowe KC, Rowley J, Ruane S, Salazar-Valenzuela D, Shultz AJ, Sidlauskas B, Sikes DS, Simmons NB, Stiassny MLJ, Streicher JW, Stuart BL, Summers AP, Tavera J, Teta P, Thompson CW, Timm RM, Torres-Carvajal O, Voelker G, Voss RS, Winker K, Witt C, Wommack EA, and Zink RM
- Subjects
- Animals, Natural History, Museums, Specimen Handling
- Abstract
Natural history museums are vital repositories of specimens, samples and data that inform about the natural world; this Formal Comment revisits a Perspective that advocated for the adoption of compassionate collection practices, querying whether it will ever be possible to completely do away with whole animal specimen collection., Competing Interests: The authors have declared that no competing interests exist., (Copyright: This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.)
- Published
- 2023
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20. Microparticles in marine mussels at regional and localized scales across the Salish Sea, Washington.
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Harris LST, Phan S, DiMarco D, Padilla-Gamiño JL, Luscombe C, and Carrington E
- Subjects
- Animals, Plastics analysis, Washington, Environmental Monitoring, Water Pollutants, Chemical analysis, Bivalvia
- Abstract
Microparticles (MP; particles <5 mm) are ubiquitous in marine environments. Understanding MP concentrations at different spatial scales in the Salish Sea, Washington, USA, can provide insight into how ecologically and economically important species may be affected. We collected mussels across the Salish Sea at regional and localized scales, chemically processed tissue to assess MP contamination, and used visual and chemical analyses for particle identification. Throughout the Salish Sea, mussel MP concentrations averaged 0.75 ± 0.09 MP g
-1 wet tissue. At a regional scale, we identified slight differences in concentrations and morphotypes of MP while at a localized scale these metrics were not significant and did not differ from controls. In a subset of particles, 20 % were identified as synthetic materials, which include polyethylene terephthalate (PET), polypropylene (PP), polystyrene (PS), and nylon. Differences in MP sources, heterogeneous transport of MP, and distinct shellfish feeding mechanisms may contribute to plastic contamination patterns in the Salish Sea., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)- Published
- 2023
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21. Mechanisms of octopus arm search behavior without visual feedback.
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Sivitilli DM, Strong T, Weertman W, Ullmann J, Smith JR, and Gire DH
- Subjects
- Animals, Arm, Feedback, Sensory, Octopodiformes physiology
- Abstract
The octopus coordinates multiple, highly flexible arms with the support of a complex distributed nervous system. The octopus's suckers, staggered along each arm, are employed in a wide range of behaviors. Many of these behaviors, such as foraging in visually occluded spaces, are executed under conditions of limited or absent visual feedback. In coordinating unseen limbs with seemingly infinite degrees of freedom across a variety of adaptive behaviors, the octopus appears to have solved a significant control problem facing the field of soft-bodied robotics. To study the strategies that the octopus uses to find and capture prey within unseen spaces, we designed and 3D printed visually occluded foraging tasks and tracked arm motion as the octopus attempted to find and retrieve a food reward. By varying the location of the food reward within these tasks, we can characterize how the arms and suckers adapt to their environment to find and capture prey. We compared these results to simulated experimental conditions performed by a model octopus arm to isolate the primary mechanisms driving our experimental observations. We found that the octopus relies on a contact-based search strategy that emerges from local sucker coordination to simplify the control of its soft, highly flexible limbs., (Creative Commons Attribution license.)
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- 2023
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22. Description of a common stauromedusa on the Pacific Coast of the United States and Canada, Haliclystus sanjuanensis new species (Cnidaria: Staurozoa).
- Author
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Mills CE, Westlake H, Hirano YM, and Miranda LS
- Abstract
Haliclystus " sanjuanensis " nomen nudum is the most common staurozoan on the west coast of the United States and Canada. This species was described in the M.S. Thesis by Gellermann (1926) and although that name has been in use nearly continuously since that time, no published description exists. Furthermore, the most popular operative name for this species has varied between several related species names over time, resulting in confusion. Herein, we provide a detailed description and synonymy of Haliclystus sanjuanensis n. sp., whose distribution is verified from Unalaska Island in the Aleutians (53.4° N, 166.8° W) in the northwest, to Santa Barbara County, California, just north of Point Conception (34.5° N, 120.5° W), in the south. Haliclystus sanjuanensis n. sp. is compared with the twelve other described species of Haliclystus and illustrations of both macroscopic and microscopic anatomy are provided. Haliclystus sanjuanensis n. sp. is unique among species of Haliclystus in the arrangement of the bright-white nematocyst spots in its calyx and the pattern of dark stripes running the length of the stalk and up the outside of the calyx., Competing Interests: The authors declare that they have no competing interests., (© 2023 Mills et al.)
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- 2023
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23. It Pays to Be Bumpy: Drag Reducing Armor in the Pacific Spiny Lumpsucker, Eumicrotremus orbis.
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Hoover RC, Hawkins OH, Rosen J, Wilson CD, Crawford CH, Holst MM, Huie JM, Summers AP, Donatelli CM, and Cohen KE
- Subjects
- Animals, Hydrodynamics, Predatory Behavior, Fishes, Perciformes
- Abstract
Armor is a multipurpose set of structures that has evolved independently at least 30 times in fishes. In addition to providing protection, armor can manipulate flow, increase camouflage, and be sexually dimorphic. There are potential tradeoffs in armor function: increased impact resistance may come at the cost of maneuvering ability; and ornate armor may offer visual or protective advantages, but could incur excess drag. Pacific spiny lumpsuckers (Eumicrotremus orbis) are covered in rows of odontic, cone-shaped armor whorls, protecting the fish from wave driven impacts and the threat of predation. We are interested in measuring the effects of lumpsucker armor on the hydrodynamic forces on the fish. Bigger lumpsuckers have larger and more complex armor, which may incur a greater hydrodynamic cost. In addition to their protective armor, lumpsuckers have evolved a ventral adhesive disc, allowing them to remain stationary in their environment. We hypothesize a tradeoff between the armor and adhesion: little fish prioritize suction, while big fish prioritize protection. Using micro-CT, we compared armor volume to disc area over lumpsucker development and built 3D models to measure changes in drag over ontogeny. We found that drag and drag coefficients decrease with greater armor coverage and vary consistently with orientation. Adhesive disc area is isometric but safety factor increases with size, allowing larger fish to remain attached in higher flows than smaller fish., (© The Author(s) 2023. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology.)
- Published
- 2023
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24. Effect of parabranchial position on ventilatory pressures in the Pacific spiny dogfish (Squalus suckleyi).
- Author
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Arnette S, Saffarian J, Ferry L, and Farina S
- Abstract
The mechanics of ventilation in elasmobranchs have been described as a two-pump system which is dependent on the generation of differential pressures between the orobranchial and parabranchial cavities. However, this general model does not take into account sources of variation in parabranchial form and function. For example, the relative pressures that drive flow in each parabranchial chamber during ventilation remain largely unexplored. To address this gap, parabranchial pressures were collected from the Pacific spiny dogfish (Squalus suckleyi, n = 12) during routine ventilation using transducers inserted into parabranchial chambers 2, 3, and 5, numbered anteriorly to posteriorly. Pressure amplitudes collected from the three chambers displayed an attenuation of pressure amplitudes posteriorly, as well as differential, modular use of parabranchial chamber five These observations have implications for the functioning of the ventilatory pump and indicate distinct ventilatory modes, leading us to propose a new model to describe ventilation in Squalus suckleyi., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier GmbH.)
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- 2023
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25. Hyposalinity reduces coordination and adhesion of sea urchin tube feet.
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Moura AJ, Garner AM, Narvaez CA, Cucchiara JP, Stark AY, and Russell MP
- Subjects
- Animals, Herbivory, Locomotion, Sea Urchins, Adhesives
- Abstract
Climate change will increase the frequency and intensity of low-salinity (hyposalinity) events in coastal marine habitats. Sea urchins are dominant herbivores in these habitats and are generally intolerant of salinity fluctuations. Their adhesive tube feet are essential for survival, effecting secure attachment and locomotion in high wave energy habitats, yet little is known about how hyposalinity impacts their function. We exposed green sea urchins (Strongylocentrotus droebachiensis) to salinities ranging from ambient (32‰) to severe (14‰) and assessed tube feet coordination (righting response, locomotion) and adhesion [disc tenacity (force per unit area)]. Righting response, locomotion and disc tenacity decreased in response to hyposalinity. Severe reductions in coordinated tube foot activities occurred at higher salinities than those that affected adhesion. The results of this study suggest moderate hyposalinities (24-28‰) have little effect on S. droebachiensis dislodgement risk and survival post-dislodgment, while severe hyposalinity (below 24‰) likely reduces movement and prevents recovery from dislodgment., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2023. Published by The Company of Biologists Ltd.)
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- 2023
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26. Plastid Genome Evolution of Two Colony-Forming Benthic Ochrosphaera neapolitana Strains (Coccolithales, Haptophyta).
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Ha JS, Lhee D, Andersen RA, Melkonian B, Melkonian M, and Yoon HS
- Subjects
- Protochlorophyllide, Plastids genetics, Evolution, Molecular, Phylogeny, Haptophyta genetics, Genome, Plastid
- Abstract
Coccolithophores are well-known haptophytes that produce small calcium carbonate coccoliths, which in turn contribute to carbon sequestration in the marine environment. Despite their important ecological role, only two of eleven haptophyte plastid genomes are from coccolithophores, and those two belong to the order Isochrysidales. Here, we report the plastid genomes of two strains of Ochrosphaera neapolitana (Coccolithales) from Spain (CCAC 3688 B) and the USA (A15,280). The newly constructed plastid genomes are the largest in size (116,906 bp and 113,686 bp, respectively) among all the available haptophyte plastid genomes, primarily due to the increased intergenic regions. These two plastid genomes possess a conventional quadripartite structure with a long single copy and short single copy separated by two inverted ribosomal repeats. These two plastid genomes share 110 core genes, six rRNAs, and 29 tRNAs, but CCAC 3688 B has an additional CDS ( ycf55 ) and one tRNA ( trnL-UAG ). Two large insertions at the intergenic regions (2 kb insertion between ycf35 and ycf45 ; 0.5 kb insertion in the middle of trnM and trnY ) were detected in the strain CCAC 3688 B. We found the genes of light-independent protochlorophyllide oxidoreductase ( chlB , chlN , and chlL ), which convert protochlorophyllide to chlorophyllide during chlorophyll biosynthesis, in the plastid genomes of O. neapolitana as well as in other benthic Isochrysidales and Coccolithales species, putatively suggesting an evolutionary adaptation to benthic habitats.
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- 2023
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27. Recording cilia activity in ctenophores: effects of nitric oxide and low molecular weight transmitters.
- Author
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Norekian TP and Moroz LL
- Abstract
Cilia are the major effectors in Ctenophores, but very little is known about their transmitter control and integration. Here, we present a simple protocol to monitor and quantify cilia activity and provide evidence for polysynaptic control of cilia coordination in ctenophores. We also screened the effects of several classical bilaterian neurotransmitters (acetylcholine, dopamine, L-DOPA, serotonin, octopamine, histamine, gamma-aminobutyric acid (GABA), L-aspartate, L-glutamate, glycine), neuropeptide (FMRFamide), and nitric oxide (NO) on cilia beating in Pleurobrachia bachei and Bolinopsis infundibulum . NO and FMRFamide produced noticeable inhibitory effects on cilia activity, whereas other tested transmitters were ineffective. These findings further suggest that ctenophore-specific neuropeptides could be major candidates for signal molecules controlling cilia activity in representatives of this early-branching metazoan lineage., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Norekian and Moroz.)
- Published
- 2023
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28. Revised classification of the Cyanidiophyceae based on plastid genome data with descriptions of the Cavernulicolales ord. nov. and Galdieriales ord. nov. (Rhodophyta).
- Author
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Park SI, Cho CH, Ciniglia C, Huang TY, Liu SL, Bustamante DE, Calderon MS, Mansilla A, McDermott T, Andersen RA, and Yoon HS
- Subjects
- Phylogeny, Rhodophyta genetics, Extremophiles, Genome, Plastid
- Abstract
The Cyanidiophyceae, an extremophilic red algal class, is distributed worldwide in extreme environments. Species grow either in acidic hot environments or in dim light conditions (e.g., "cave Cyanidium"). The taxonomy and classification systems are currently based on morphological, eco-physiological, and molecular phylogenetic characters; however, previous phylogenetic results showed hidden diversity of the Cyanidiophyceae and suggested a revision of the classification system. To clarify phylogenetic relationships within this red algal class, we employ a phylogenomic approach based on 15 plastomes (10 new) and 15 mitogenomes (seven new). Our phylogenies show consistent relationships among four lineages (Galdieria, "cave Cyanidium", Cyanidium, and Cyanidioschyzon lineages). Each lineage is distinguished by organellar genome characteristics. The "cave Cyanidium" lineage is a distinct clade that diverged after the Galdieria clade but within a larger monophyletic clade that included the Cyanidium and Cyanidioschyzon lineages. Because the "cave Cyanidium" lineage is a mesophilic lineage that differs substantially from the other three thermoacidophilic lineages, we describe it as a new order (Cavernulicolales). Based on this evidence, we reclassified the Cyanidiophyceae into four orders: Cyanidiales, Cyanidioschyzonales, Cavernulicolales ord. nov., and Galdieriales ord. nov. The genetic distance among these four orders is comparable to, or greater than, the distances found between other red algal orders and subclasses. Three new genera (Cavernulicola, Gronococcus, Sciadococcus), five new species (Galdieria javensis, Galdieria phlegrea, Galdieria yellowstonensis, Gronococcus sybilensis, Sciadococcus taiwanensis), and a new nomenclatural combination (Cavernulicola chilensis) are proposed., (© 2023 Phycological Society of America.)
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- 2023
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29. Nitric oxide suppresses cilia activity in ctenophores.
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Norekian TP and Moroz LL
- Abstract
Cilia are the major effectors in Ctenophores, but very little is known about their transmitter control and integration. Here, we present a simple protocol to monitor and quantify cilia activity in semi-intact preparations and provide evidence for polysynaptic control of cilia coordination in ctenophores. Next, we screen the effects of several classical bilaterian neurotransmitters (acetylcholine, dopamine, L-DOPA, serotonin, octopamine, histamine, gamma-aminobutyric acid (GABA), L-aspartate, L-glutamate, glycine), neuropeptides (FMRFamide), and nitric oxide (NO) on cilia beating in Pleurobrachia bachei and Bolinopsis infundibulum . Only NO inhibited cilia beating, whereas other tested transmitters were ineffective. These findings further suggest that ctenophore-specific neuropeptides could be major candidate signaling molecules controlling cilia activity in representatives of this early-branching metazoan lineage.
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- 2023
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30. Feeding preferences and the effect of temperature on feeding rates of the graceful kelp crab, Pugettia gracilis .
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Johnson KH, Dobkowski KA, Seroy SK, Fox S, and Meenan N
- Subjects
- Animals, Ecosystem, Temperature, Seafood, Kelp, Brachyura, Seaweed
- Abstract
Graceful kelp crabs ( Pugettia gracilis ) are abundant consumers in shallow subtidal ecosystems of the Salish Sea. These dynamic habitats are currently experiencing multiple changes including invasion by non-native seaweeds and ocean warming. However, little is known about P. gracilis' foraging ecology, therefore we investigated their feeding preferences between native and invasive food sources, as well as feeding rates at elevated temperatures to better assess their role in changing coastal food webs. To quantify crab feeding preferences, we collected P. gracilis from San Juan Island, WA and conducted no-choice and choice experiments with two food sources: the native kelp, Nereocystis luetkeana, and the invasive seaweed, Sargassum muticum . In no-choice experiments, P. gracilis ate equal amounts of N. luetkeana and S. muticum . However, in choice experiments, P. gracilis preferred N. luetkeana over S. muticum . To test effects of temperature on these feeding rates, we exposed P. gracilis to ambient (11.5 ± 1.3 °C) or elevated (19.5 ± 1.8 °C) temperature treatments and measured consumption of the preferred food type, N. luetkeana. Crabs exposed to elevated temperatures ate significantly more than those in the ambient treatment. Our study demonstrates the diet flexibility of P. gracilis , suggesting they may be able to exploit increasing populations of invasive S. muticum in the Salish Sea . Warming ocean temperatures may also prompt P. gracilis to increase feeding, exacerbating harmful impacts on N. luetkeana, which is already vulnerable to warming and invasive competitors., Competing Interests: The authors declare there are no competing interests., (©2023 Johnson et al.)
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- 2023
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31. Formation of a fringe: A look inside baleen morphology using a multimodal visual approach.
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Vandenberg ML, Cohen KE, Rubin RD, Goldbogen JA, Summers AP, Paig-Tran EWM, and Kahane-Rapport SR
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- Animals, X-Ray Microtomography, Whales anatomy & histology, Jaw anatomy & histology, Feeding Behavior, Mouth anatomy & histology
- Abstract
Filter-feeding has been present for hundreds of millions of years, independently evolving in aquatic vertebrates' numerous times. Mysticete whales are a group of gigantic, marine filter-feeders that are defined by their fringed baleen and are divided into two groups: balaenids and rorquals. Recent studies have shown that balaenids likely feed using a self-cleaning, cross-flow filtration mechanism where food particles are collected and then swept to the esophagus for swallowing. However, it is unclear how filtering is achieved in the rorquals (Balaenopteridae). Lunging rorqual whales engulf enormous masses of both prey and water; the prey is then separated from the water through baleen plates lining the length of their upper jaw and positioned perpendicular to flow. Rorqual baleen is composed of both major (larger) and minor (smaller) keratin plates containing embedded fringe that extends into the whale's mouth, forming a filtering fringe. We used a multimodal approach, including microcomputed tomography (µCT) and scanning electron microscopy (SEM), to visualize and describe the variability in baleen anatomy across five species of rorqual whales, spanning two orders of magnitude in body length. For most morphological measurements, larger whales exhibited hypoallometry relative to body length. µCT and SEM revealed that the major and minor plates break away from the mineralized fringes at variable distances from the gums. We proposed a model for estimating the effective pore size to determine whether flow scales with body length or prey size across species. We found that pore size is likely not a proxy for prey size but instead, may reflect changes in resistance through the filter that affect fluid flow., (© 2023 Wiley Periodicals LLC.)
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- 2023
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32. Drosophila postembryonic nervous system development: a model for the endocrine control of development.
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Truman JW and Riddiford LM
- Subjects
- Animals, Ecdysone, Gene Expression Regulation, Developmental, Larva genetics, Metamorphosis, Biological genetics, Nervous System, Models, Animal, Drosophila genetics, Ecdysteroids
- Abstract
During postembryonic life, hormones, including ecdysteroids, juvenile hormones, insulin-like peptides, and activin/TGFβ ligands act to transform the larval nervous system into an adult version, which is a fine-grained mosaic of recycled larval neurons and adult-specific neurons. Hormones provide both instructional signals that make cells competent to undergo developmental change and timing cues to evoke these changes across the nervous system. While touching on all the above hormones, our emphasis is on the ecdysteroids, ecdysone and 20-hydroxyecdysone (20E). These are the prime movers of insect molting and metamorphosis and are involved in all phases of nervous system development, including neurogenesis, pruning, arbor outgrowth, and cell death. Ecdysteroids appear as a series of steroid peaks that coordinate the larval molts and the different phases of metamorphosis. Each peak directs a stereotyped cascade of transcription factor expression. The cascade components then direct temporal programs of effector gene expression, but the latter vary markedly according to tissue and life stage. The neurons read the ecdysteroid titer through various isoforms of the ecdysone receptor, a nuclear hormone receptor. For example, at metamorphosis the pruning of larval neurons is mediated through the B isoforms, which have strong activation functions, whereas subsequent outgrowth is mediated through the A isoform through which ecdysteroids play a permissive role to allow local tissue interactions to direct outgrowth. The major circulating ecdysteroid can also change through development. During adult development ecdysone promotes early adult patterning and differentiation while its metabolite, 20E, later evokes terminal adult differentiation., (© The Author(s) 2023. Published by Oxford University Press on behalf of the Genetics Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
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- 2023
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33. Hydrofoil-like legs help stream mayfly larvae to stay on the ground.
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Ditsche P, Hoffmann F, Kaehlert S, Kesel A, and Gorb S
- Subjects
- Animals, Larva, Biomechanical Phenomena, Rivers, Insecta physiology, Ephemeroptera
- Abstract
Adaptations to flow have already been in the focus of early stream research, but till today morphological adaptations of stream insects are hardly understood. While most previous stream research focused on drag, the effects of lift on ground-living stream insects have been often overlooked. Stream mayfly larvae Ecdyonurus sp. graze on algae on top of the stones and therefore inhabit current exposed places in streams. They have a dorso-ventrally flattened body shape, which is known to reduce drag. However, this body shape enhances lift too, increasing the danger for the animal of getting detached from the substrate. Using microscopic techniques, 3D-printing, and drag and lift measurements in a wind tunnel, our experiments show that the widened femora of Ecdyonurus sp. can generate negative lift, contributing to counterbalance the (positive) lift of the overall body shape. The larvae can actively regulate the amount of lift by adjusting the femur's tilt or optimizing the distance to the ground. This shows that morphological adaptations of benthic stream insects can be very elaborate and can reach far beyond adaptations of the overall body shape. In the presented case, Ecdyonurus sp. takes advantage of the flow to overcome the flow's challenges., (© 2023. The Author(s).)
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- 2023
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34. Sunflower sea star predation on urchins can facilitate kelp forest recovery.
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Galloway AWE, Gravem SA, Kobelt JN, Heady WN, Okamoto DK, Sivitilli DM, Saccomanno VR, Hodin J, and Whippo R
- Subjects
- Animals, Humans, Food Chain, Starfish, Predatory Behavior, Forests, Sea Urchins physiology, Ecosystem, Helianthus, Kelp, Asteraceae, Strongylocentrotus purpuratus
- Abstract
The recent collapse of predatory sunflower sea stars ( Pycnopodia helianthoides ) owing to sea star wasting disease (SSWD) is hypothesized to have contributed to proliferation of sea urchin barrens and losses of kelp forests on the North American west coast. We used experiments and a model to test whether restored Pycnopodia populations may help recover kelp forests through their consumption of nutritionally poor purple sea urchins ( Strongylocentrotus purpuratus ) typical of barrens. Pycnopodia consumed 0.68 S. purpuratus d
-1 , and our model and sensitivity analysis shows that the magnitude of recent Pycnopodia declines is consistent with urchin proliferation after modest sea urchin recruitment, and even small Pycnopodia recoveries could generally lead to lower densities of sea urchins that are consistent with kelp-urchin coexistence. Pycnopodia seem unable to chemically distinguish starved from fed urchins and indeed have higher predation rates on starved urchins owing to shorter handling times. These results highlight the importance of Pycnopodia in regulating purple sea urchin populations and maintaining healthy kelp forests through top-down control. The recovery of this important predator to densities commonly found prior to SSWD, whether through natural means or human-assisted reintroductions, may therefore be a key step in kelp forest restoration at ecologically significant scales.- Published
- 2023
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35. Structure and formation of the perforated theca defining the Pelagophyceae (Heterokonta), and three new genera that substantiate the diverse nature of the class.
- Author
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Wetherbee R, Bringloe TT, van de Meene A, Andersen RA, and Verbruggen H
- Subjects
- Phylogeny, Plastids genetics, DNA, Ribosomal, Australia, Stramenopiles genetics
- Abstract
The pelagophytes, a morphologically diverse class of marine heterokont algae, have been historically united only by DNA sequences. Recently we described a novel perforated theca (PT) encasing cells from the Pelagophyceae and hypothesized it may be the first morphological feature to define the class. Here we consolidate that observation, describing a PT for the first time in an additional seven pelagophyte genera, including three genera new to science. We established clonal cultures of pelagophytes collected from intertidal pools located around Australia, and established phylogenetic trees based on nuclear 18S rDNA and plastid rbcL, psaA, psaB, psbA and psbC gene sequences that led to the discovery of three new species: Wyeophycus julieharrissiae and Chromopallida australis form a distinct lineage along with Ankylochrysis lutea within the Pelagomonadales, while Pituiglomerulus capricornicus is sister genus to Chrysocystis fragilis in the Chrysocystaceae (Sarcinochrysidales). Using fixation by high-pressure freezing for electron microscope observations, a distinctive PT was observed in the three new genera described in this paper, as well as four genera not previously investigated: Chrysoreinhardia, Sargassococcus, Sungminbooa and Andersenia. The mechanism of PT formation is novel, being fabricated from rafts in Golgi-derived vesicles before being inserted into an established PT. Extracellular wall and/or mucilage layers assemble exterior to the PT in most pelagophytes, the materials likewise secreted by Golgi-derived vesicles, though the mechanism of secretion is novel. Secretory vesicles never fuse with the plasma membrane as in classic secretion and deposition, but rather relocate extracellularly beneath the PT and disintegrate, the contents having to pass through the PT prior to wall and/or mucilage synthesis. This study substantiates the diverse nature of pelagophytes, and provides further evidence that the PT is a sound morphological feature to define the Pelagophyceae, with all 14 of the 20 known genera studied to date by TEM possessing a PT., (© 2022 The Authors. Journal of Phycology published by Wiley Periodicals LLC on behalf of Phycological Society of America.)
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- 2023
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36. Lip service: Histological phenotypes correlate with diet and feeding ecology in herbivorous pacus.
- Author
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Cohen KE, Lucanus O, Summers AP, and Kolmann MA
- Subjects
- Animals, Feeding Behavior physiology, Jaw anatomy & histology, Mammals, Tongue, Characiformes, Diet, Lip
- Abstract
Complex prey processing requires the repositioning of food between the teeth, as modulated by a soft tissue appendage like a tongue or lips. In this study, we trace the evolution of lips and ligaments, which are used during prey capture and prey processing in an herbivorous group of fishes. Pacus (Serrasalmidae) are Neotropical freshwater fishes that feed on leaves, fruits, and seeds. These prey are hard or tough, require high forces to fracture, contain abrasive or caustic elements, or deform considerably before failure. Pacus are gape-limited and do not have the pharyngeal jaws many bony fishes use to dismantle and/or transport prey. Despite their gape limitation, pacus feed on prey larger than their mouths, relying on robust teeth and a hypertrophied lower lip for manipulation and breakdown of food. We used histology to compare the lip morphology across 14 species of pacus and piranhas to better understand this soft tissue. We found that frugivorous pacus have larger, more complex lips which are innervated and folded at their surface, while grazing species have callused, mucus-covered lips. Unlike mammalian lips or tongues, pacu lips lack any intrinsic skeletal or smooth muscle. This implies that pacu lips lack dexterity; however, we found a novel connection to the primordial ligament which suggests that the lips are actuated by the jaw adductors. We propose that pacus combine hydraulic repositioning of prey inside the buccal cavity with direct oral manipulation, the latter using a combination of a morphologically heterodont dentition and compliant lips for reorienting food., (© 2022 American Association for Anatomy.)
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- 2023
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37. Every refuge has its price: Ostreobium as a model for understanding how algae can live in rock and stay in business.
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Tandon K, Pasella MM, Iha C, Ricci F, Hu J, O'Kelly CJ, Medina M, Kühl M, and Verbruggen H
- Subjects
- Animals, Coral Reefs, Ecosystem, Chlorophyta, Anthozoa
- Abstract
Ostreobium is a siphonous green alga in the Bryopsidales (Chlorophyta) that burrows into calcium carbonate (CaCO
3 ) substrates. In this habitat, it lives under environmental conditions unusual for an alga (i.e., low light and low oxygen) and it is a major agent of carbonate reef bioerosion. In coral skeletons, Ostreobium can form conspicuous green bands recognizable by the naked eye and it is thought to contribute to the coral's nutritional needs. With coral reefs in global decline, there is a renewed focus on understanding Ostreobium biology and its roles in the coral holobiont. This review summarizes knowledge on Ostreobium's morphological structure, biodiversity and evolution, photosynthesis, mechanism of bioerosion and its role as a member of the coral holobiont. We discuss the resources available to study Ostreobium biology, lay out some of the uncharted territories in Ostreobium biology and offer perspectives for future research., (Copyright © 2022 Elsevier Ltd. All rights reserved.)- Published
- 2023
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38. Metamorphosis of memory circuits in Drosophila reveals a strategy for evolving a larval brain.
- Author
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Truman JW, Price J, Miyares RL, and Lee T
- Subjects
- Animals, Larva physiology, Brain, Axons, Mushroom Bodies physiology, Drosophila melanogaster physiology, Metamorphosis, Biological, Drosophila physiology, Neurons physiology
- Abstract
Mushroom bodies (MB) of adult Drosophila have a core of thousands of Kenyon neurons; axons of the early-born g class form a medial lobe and those from later-born α'β' and αβ classes form both medial and vertical lobes. The larva, however, hatches with only γ neurons and forms a vertical lobe 'facsimile' using larval-specific axon branches from its γ neurons. MB input (MBINs) and output (MBONs) neurons divide the Kenyon neuron lobes into discrete computational compartments. The larva has 10 such compartments while the adult has 16. We determined the fates of 28 of the 32 MBONs and MBINs that define the 10 larval compartments. Seven compartments are subsequently incorporated into the adult MB; four of their MBINs die, while 12 MBINs/MBONs remodel to function in adult compartments. The remaining three compartments are larval specific. At metamorphosis their MBIN/MBONs trans-differentiate, leaving the MB for other adult brain circuits. The adult vertical lobes are made de novo using MBONs/MBINs recruited from pools of adult-specific neurons. The combination of cell death, compartment shifting, trans-differentiation, and recruitment of new neurons result in no larval MBIN-MBON connections being maintained through metamorphosis. At this simple level, then, we find no anatomical substrate for a memory trace persisting from larva to adult. The adult phenotype of the trans-differentiating neurons represents their evolutionarily ancestral phenotype while their larval phenotype is a derived adaptation for the larval stage. These cells arise primarily within lineages that also produce permanent MBINs and MBONs, suggesting that larval specifying factors may allow information related to birth-order or sibling identity to be interpreted in a modified manner in the larva to allow these neurons to acquire larval phenotypic modifications. The loss of such factors at metamorphosis then allows these neurons to revert to their ancestral functions in the adult., Competing Interests: JT, JP, RM, TL No competing interests declared, (© 2023, Truman et al.)
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- 2023
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39. The effects of temperature and pH on the reproductive ecology of sand dollars and sea urchins: Impacts on sperm swimming and fertilization.
- Author
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Leuchtenberger SG, Daleo M, Gullickson P, Delgado A, Lo C, and Nishizaki MT
- Subjects
- Male, Animals, Temperature, Hydrogen-Ion Concentration, Semen, Sea Urchins, Spermatozoa, Water, Fertilization, Sperm Motility, Seawater
- Abstract
In an era of climate change, impacts on the marine environment include warming and ocean acidification. These effects can be amplified in shallow coastal regions where conditions often fluctuate widely. This type of environmental variation is potentially important for many nearshore species that are broadcast spawners, releasing eggs and sperm into the water column for fertilization. We conducted two experiments to investigate: 1) the impact of water temperature on sperm swimming characteristics and fertilization rate in sand dollars (Dendraster excentricus; temperatures 8-38°C) and sea urchins (Mesocentrotus franciscanus; temperatures 8-28°C) and; 2) the combined effects of multiple stressors (water temperature and pH) on these traits in sand dollars. We quantify thermal performance curves showing that sand dollar fertilization rates, sperm swimming velocities, and sperm motility display remarkably wide thermal breadths relative to red urchins, perhaps reflecting the wider range of water temperatures experienced by sand dollars at our field sites. For sand dollars, both temperature (8, 16, 24°C) and pH (7.1, 7.5, 7.9) affected fertilization but only temperature influenced sperm swimming velocity and motility. Although sperm velocities and fertilization were positively correlated, our fertilization kinetics model dramatically overestimated measured rates and this discrepancy was most pronounced under extreme temperature and pH conditions. Our results suggest that environmental stressors like temperature and pH likely impair aspects of the reproductive process beyond simple sperm swimming behavior., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2022 Leuchtenberger et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
- Published
- 2022
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40. Automated landmarking via multiple templates.
- Author
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Zhang C, Porto A, Rolfe S, Kocatulum A, and Maga AM
- Subjects
- Pregnancy, Female, Humans, Phenotype, Software, Biological Evolution, Labor, Obstetric
- Abstract
Manually collecting landmarks for quantifying complex morphological phenotypes can be laborious and subject to intra and interobserver errors. However, most automated landmarking methods for efficiency and consistency fall short of landmarking highly variable samples due to the bias introduced by the use of a single template. We introduce a fast and open source automated landmarking pipeline (MALPACA) that utilizes multiple templates for accommodating large-scale variations. We also introduce a K-means method of choosing the templates that can be used in conjunction with MALPACA, when no prior information for selecting templates is available. Our results confirm that MALPACA significantly outperforms single-template methods in landmarking both single and multi-species samples. K-means based template selection can also avoid choosing the worst set of templates when compared to random template selection. We further offer an example of post-hoc quality check for each individual template for further refinement. In summary, MALPACA is an efficient and reproducible method that can accommodate large morphological variability, such as those commonly found in evolutionary studies. To support the research community, we have developed open-source and user-friendly software tools for performing K-means multi-templates selection and MALPACA., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2022 Zhang et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
- Published
- 2022
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41. Internal vertebral morphology of bony fishes matches the mechanical demands of different environments.
- Author
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Baxter D, Cohen KE, Donatelli CM, and Tytell ED
- Abstract
Fishes have repeatedly evolved characteristic body shapes depending on how close they live to the substrate. Pelagic fishes live in open water and typically have narrow, streamlined body shapes; benthic and demersal fishes live close to the substrate; and demersal fishes often have deeper bodies. These shape differences are often associated with behavioral differences: pelagic fishes swim nearly constantly, demersal fishes tend to maneuver near the substrate, and benthic fishes often lie in wait on the substrate. We hypothesized that these morphological and behavioral differences would be reflected in the mechanical properties of the body, and specifically in vertebral column stiffness, because it is an attachment point for the locomotor musculature and a central axis for body bending. The vertebrae of bony fishes are composed of two cones connected by a foramen, which is filled by the notochord. Since the notochord is more flexible than bony vertebral centra, we predicted that pelagic fishes would have narrower foramina or shallower cones, leading to less notochordal material and a stiffer vertebral column which might support continuous swimming. In contrast, we predicted that benthic and demersal fishes would have more notochordal material, making the vertebral column more flexible for diverse behaviors in these species. We therefore examined vertebral morphology in 79 species using micro-computed tomography scans. Six vertebral features were measured including notochordal foramen diameter, centrum body length, and the cone angles and diameters for the anterior and posterior vertebral cones, along with body fineness. Using phylogenetic generalized least squares analyses, we found that benthic and pelagic species differed significantly, with larger foramina, shorter centra, and larger cones in benthic species. Thus, morphological differences in the internal shape of the vertebrae of fishes are consistent with a stiffer vertebral column in pelagic fishes and with a more flexible vertebral column in benthic species., Competing Interests: The authors declare that they have no competing interests., (© 2022 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)
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- 2022
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42. Sticky, stickier and stickiest - a comparison of adhesive performance in clingfish, lumpsuckers and snailfish.
- Author
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Huie JM, Wainwright DK, Summers AP, and Cohen KE
- Subjects
- Animals, X-Ray Microtomography, Fishes, Ecosystem, Adhesives, Perciformes
- Abstract
The coastal waters of the North Pacific are home to the northern clingfish (Gobiesox maeandricus), Pacific spiny lumpsucker (Eumicrotremus orbis) and marbled snailfish (Liparis dennyi) - three fishes that have evolved ventral adhesive discs. Clingfish adhesive performance has been studied extensively, but relatively little is known about the performance of other sticky fishes. Here, we compared the peak adhesive forces and work to detachment of clingfish, lumpsuckers and snailfish on surfaces of varying roughness and over ontogeny. We also investigated the morphology of their adhesive discs through micro-computed tomography scanning and scanning electron microscopy. We found evidence that adhesive performance is tied to the intensity and variability of flow regimes in the fishes' habitats. The northern clingfish generates the highest adhesive forces and lives in the rocky intertidal zone where it must resist exposure to crashing waves. Lumpsuckers and snailfish both generate only a fraction of the clingfish's adhesive force, but live more subtidal where currents are slower and less variable. However, lumpsuckers generate more adhesive force relative to their body weight than snailfish, which we attribute to their higher-drag body shape and frequent bouts into the intertidal zone. Even so, the performance and morphology data suggest that snailfish adhesive discs are stiffer and built more efficiently than lumpsucker discs. Future studies should focus on sampling additional diversity and designing more ecologically relevant experiments when investigating differences in adhesive performance., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2022. Published by The Company of Biologists Ltd.)
- Published
- 2022
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43. The Diversity and Functional Capacity of Microbes Associated with Coastal Macrophytes.
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Miranda K, Weigel BL, Fogarty EC, Veseli IA, Giblin AE, Eren AM, and Pfister CA
- Subjects
- Rhizosphere, Nitrogen metabolism, Sulfur metabolism, Metagenome genetics, Microbiota
- Abstract
Coastal marine macrophytes exhibit some of the highest rates of primary productivity in the world. They have been found to host a diverse set of microbes, many of which may impact the biology of their hosts through metabolisms that are unique to microbial taxa. Here, we characterized the metabolic functions of macrophyte-associated microbial communities using metagenomes collected from 2 species of kelp ( Laminaria setchellii and Nereocystis luetkeana ) and 3 marine angiosperms ( Phyllospadix scouleri , P. serrulatus , and Zostera marina ), including the rhizomes of two surfgrass species ( Phyllospadix spp.), the seagrass Zostera marina , and the sediments surrounding P. scouleri and Z. marina . Using metagenomic sequencing, we describe 63 metagenome-assembled genomes (MAGs) that potentially benefit from being associated with macrophytes and may contribute to macrophyte fitness through their metabolic activity. Host-associated metagenomes contained genes for the use of dissolved organic matter from hosts and vitamin (B
1 , B2 , B7 , B12 ) biosynthesis in addition to a range of nitrogen and sulfur metabolisms that recycle dissolved inorganic nutrients into forms more available to the host. The rhizosphere of surfgrass and seagrass contained genes for anaerobic microbial metabolisms, including nifH genes associated with nitrogen fixation, despite residing in a well-mixed and oxygenated environment. The range of oxygen environments engineered by macrophytes likely explains the diversity of both oxidizing and reducing microbial metabolisms and contributes to the functional capabilities of microbes and their influences on carbon and nitrogen cycling in nearshore ecosystems. IMPORTANCE Kelps, seagrasses, and surfgrasses are ecosystem engineers on rocky shorelines, where they show remarkably high levels of primary production. Through analysis of their associated microbial communities, we found a variety of microbial metabolisms that may benefit the host, including nitrogen metabolisms, sulfur oxidation, and the production of B vitamins. In turn, these microbes have the genetic capabilities to assimilate the dissolved organic compounds released by their macrophyte hosts. We describe a range of oxygen environments associated with surfgrass, including low-oxygen microhabitats in their rhizomes that host genes for nitrogen fixation. The tremendous productivity of coastal seaweeds and seagrasses is likely due in part to the activities of associated microbes, and an increased understanding of these associations is needed.- Published
- 2022
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44. Algal solutions: Transforming marine aquaculture from the bottom up for a sustainable future.
- Author
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Greene CH and Scott-Buechler CM
- Subjects
- Aquaculture
- Abstract
Today's global food production system is unsustainable. Shifting the focus of marine aquaculture down the food chain to algae could help meet projected global nutritional demands while simultaneously improving overall environmental sustainability and ocean health., Competing Interests: The authors have declared that no competing interests exist.
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- 2022
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45. Bone Density Variation in Rattails ( Macrouridae, Gadiformes ): Buoyancy, Depth, Body Size, and Feeding.
- Author
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Martin RP, Dias AS, Summers AP, and Gerringer ME
- Abstract
Extreme abiotic factors in deep-sea environments, such as near-freezing temperatures, low light, and high hydrostatic pressure, drive the evolution of adaptations that allow organisms to survive under these conditions. Pelagic and benthopelagic fishes that have invaded the deep sea face physiological challenges from increased compression of gasses at depth, which limits the use of gas cavities as a buoyancy aid. One adaptation observed in deep-sea fishes to increase buoyancy is a decrease of high-density tissues. In this study, we analyze mineralization of high-density skeletal tissue in rattails (family Macrouridae), a group of widespread benthopelagic fishes that occur from surface waters to greater than 7000 m depth. We test the hypothesis that rattail species decrease bone density with increasing habitat depth as an adaptation to maintaining buoyancy while living under high hydrostatic pressures. We performed micro-computed tomography (micro-CT) scans on 15 species and 20 specimens of rattails and included two standards of known hydroxyapatite concentration (phantoms) to approximate voxel brightness to bone density. Bone density was compared across four bones (eleventh vertebra, lower jaw, pelvic girdle, and first dorsal-fin pterygiophore). On average, the lower jaw was significantly denser than the other bones. We found no correlation between bone density and depth or between bone density and phylogenetic relationships. Instead, we observed that bone density increases with increasing specimen length within and between species. This study adds to the growing body of work that suggests bone density can increase with growth in fishes, and that bone density does not vary in a straightforward way with depth., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology.)
- Published
- 2022
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46. Speciation of pelagic zooplankton: Invisible boundaries can drive isolation of oceanic ctenophores.
- Author
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Johnson SB, Winnikoff JR, Schultz DT, Christianson LM, Patry WL, Mills CE, and Haddock SHD
- Abstract
The study of evolution and speciation in non-model systems provides us with an opportunity to expand our understanding of biodiversity in nature. Connectivity studies generally focus on species with obvious boundaries to gene flow, but in open-ocean environments, such boundaries are difficult to identify. Due to the lack of obvious boundaries, speciation and population subdivision in the pelagic environment remain largely unexplained. Comb jellies (Phylum Ctenophora) are mostly planktonic gelatinous invertebrates, many of which are considered to have freely interbreeding distributions worldwide. It is thought that the lobate ctenophore Bolinopsis infundibulum is distributed throughout cooler northern latitudes and B. vitrea warmer. Here, we examined the global population structure for species of Bolinopsis with genetic and morphological data. We found distinct evolutionary patterns within the genus, where B. infundibulum had a broad distribution from northern Pacific to Atlantic waters despite many physical barriers, while other species were geographically segregated despite few barriers. Divergent patterns of speciation within the genus suggest that oceanic currents, sea-level, and geological changes over time can act as either barriers or aids to dispersal in the pelagic environment. Further, we used population genomic data to examine evolution in the open ocean of a distinct lineage of Bolinopsis ctenophores from the North Eastern Pacific. Genetic information and morphological observations validated this as a separate species, Bolinopsis microptera , which was previously described but has recently been called B. infundibulum . We found that populations of B. microptera from California were in cytonuclear discordance, which indicates a secondary contact zone for previously isolated populations. Discordance at this scale is rare, especially in a continuous setting., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Johnson, Winnikoff, Schultz, Christianson, Patry, Mills and Haddock.)
- Published
- 2022
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47. Assessment of the impacts of an unprecedented heatwave on intertidal shellfish of the Salish Sea.
- Author
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Raymond WW, Barber JS, Dethier MN, Hayford HA, Harley CDG, King TL, Paul B, Speck CA, Tobin ED, Raymond AET, and McDonald PS
- Subjects
- Fisheries, Shellfish
- Published
- 2022
- Full Text
- View/download PDF
48. Biomechanics of the jaws of spotted ratfish.
- Author
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Herbert AM, Dean MN, Summers AP, and Wilga CD
- Subjects
- Animals, Biomechanical Phenomena, Feeding Behavior, Fishes, Jaw anatomy & histology, Sharks anatomy & histology, Skates, Fish anatomy & histology
- Abstract
Elasmobranch fishes (sharks, skates and rays) consume prey of a variety of sizes and properties, and the feeding mechanism typically reflects diet. Spotted ratfish, Hydrolagus colliei (Holocephali, sister group of elasmobranchs), consume both hard and soft prey; however, the morphology of the jaws does not reflect the characteristics typical of durophagous elasmobranchs. This study investigated the mechanical properties and morphological characteristics of the jaws of spotted ratfish over ontogeny, including strain, stiffness and second moment of area, to evaluate the biomechanical function of the feeding structures. Compressive stiffness of the jaws (E=13.51-21.48 MPa) is similar to that of silicone rubber, a very flexible material. In Holocephali, the upper jaw is fused to the cranium; we show that this fusion reduces deformation experienced by the upper jaw during feeding. The lower jaw resists bending primarily in the posterior half of the jaw, which occludes with the region of the upper jaw that is wider and flatter, thus potentially providing an ideal location for the lower jaw to crush or crack prey. The mechanical properties and morphology of the feeding apparatus of spotted ratfish suggest that while the low compressive stiffness is a material limit of the jaw cartilage, spotted ratfish, and perhaps all holocephalans, evolved structural solutions (i.e. fused upper jaw, shape variation along lower jaw) to meet the demands of a durophagous diet., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2022. Published by The Company of Biologists Ltd.)
- Published
- 2022
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49. The role of heterotopy and heterochrony during morphological diversification of otocephalan epibranchial organs.
- Author
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Cohen KE, Ackles AL, and Hernandez LP
- Subjects
- Animals, Branchial Region, Phylogeny, Biological Evolution, Fishes
- Abstract
Epibranchial organs (EBOs), found in at least five of the eight otomorphan families, are used to aggregate small prey inside the buccopharyngeal cavity and range in morphological complexity from a singular, small slit on the pharyngeal roof to several, elongated soft tissue tubes. Despite broad phylogenetic representation, little is known about the origin, development, or evolution of EBOs. We hypothesize that both heterochronic and heterotopic changes throughout the evolution of EBOs are at the root of their morphological diversity. Heterochrony is a foundational explanation in developmental studies, however, heterotopy, a developmental change in spatial or topographical relationships, can have even more profound effects on a given structure but has received relatively little attention. Here, we investigate how developmental mechanisms may drive morphological diversity of EBOs within otomorphan fishes. We compare early pharyngeal development in three species, Anchoa mitchilli (Engraulidae) which has the most basic EBO, B. tyrannus (Clupeidae) which has a more complex EBO, and Hypophthalmichthys molitrix (Cyprinidae) which has the most complex EBO yet described. Using branchial arch growth rates and morphological analyses, we illustrate how both heterochronic and heterotopic mechanisms are responsible for some of the phenotypic diversity seen in otomorphan EBOs. Importantly, we also identify conserved developmental patterns that further our understanding of how EBOs may have first originated and evolved across actinopterygian fishes., (© 2022 Wiley Periodicals LLC.)
- Published
- 2022
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50. Dual spring force couples yield multifunctionality and ultrafast, precision rotation in tiny biomechanical systems.
- Author
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Sutton GP, St Pierre R, Kuo CY, Summers AP, Bergbreiter S, Cox S, and Patek SN
- Subjects
- Animals, Biomechanical Phenomena, Mandible physiology, Movement physiology, Ants physiology
- Abstract
Small organisms use propulsive springs rather than muscles to repeatedly actuate high acceleration movements, even when constrained to tiny displacements and limited by inertial forces. Through integration of a large kinematic dataset, measurements of elastic recoil, energetic math modeling and dynamic math modeling, we tested how trap-jaw ants (Odontomachus brunneus) utilize multiple elastic structures to develop ultrafast and precise mandible rotations at small scales. We found that O. brunneus develops torque on each mandible using an intriguing configuration of two springs: their elastic head capsule recoils to push and the recoiling muscle-apodeme unit tugs on each mandible. Mandibles achieved precise, planar, circular trajectories up to 49,100 rad s-1 (470,000 rpm) when powered by spring propulsion. Once spring propulsion ended, the mandibles moved with unconstrained and oscillatory rotation. We term this mechanism a 'dual spring force couple', meaning that two springs deliver energy at two locations to develop torque. Dynamic modeling revealed that dual spring force couples reduce the need for joint constraints and thereby reduce dissipative joint losses, which is essential to the repeated use of ultrafast, small systems. Dual spring force couples enable multifunctionality: trap-jaw ants use the same mechanical system to produce ultrafast, planar strikes driven by propulsive springs and for generating slow, multi-degrees of freedom mandible manipulations using muscles, rather than springs, to directly actuate the movement. Dual spring force couples are found in other systems and are likely widespread in biology. These principles can be incorporated into microrobotics to improve multifunctionality, precision and longevity of ultrafast systems., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2022. Published by The Company of Biologists Ltd.)
- Published
- 2022
- Full Text
- View/download PDF
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