Sample records for lamarck echinodermata echinoidea
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Ziegler, Alexander; Faber, Cornelius; Bartolomaeus, Thomas
2009-06-09
The axial complex of echinoderms (Echinodermata) is composed of various primary and secondary body cavities that interact with each other. In sea urchins (Echinoidea), structural differences of the axial complex in "regular" and irregular species have been observed, but the reasons underlying these differences are not fully understood. In addition, a better knowledge of axial complex diversity could not only be useful for phylogenetic inferences, but improve also an understanding of the function of this enigmatic structure. We therefore analyzed numerous species of almost all sea urchin orders by magnetic resonance imaging, dissection, histology, and transmission electron microscopy and compared the results with findings from published studies spanning almost two centuries. These combined analyses demonstrate that the axial complex is present in all sea urchin orders and has remained structurally conserved for a long time, at least in the "regular" species. Within the Irregularia, a considerable morphological variation of the axial complex can be observed with gradual changes in topography, size, and internal architecture. These modifications are related to the growing size of the gastric caecum as well as to the rearrangement of the morphology of the digestive tract as a whole. The structurally most divergent axial complex can be observed in the highly derived Atelostomata in which the reorganization of the digestive tract is most pronounced. Our findings demonstrate a structural interdependence of various internal organs, including digestive tract, mesenteries, and the axial complex.
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Oscar Holguin Quiñones
2000-12-01
Full Text Available Para evaluar distribución, abundancia y densidades de erizos, estrellas y pepinos de mar en la Bahía de Loreto se empleó un transecto de 50 metros, por duplicado, con un margen de observación de 2.5 m a cada lado del mismo por estación y fecha de muestreo. Se observaron mayores abundancias y densidades en la clase Echinoidea: Echinometra vanbrunti (94.1+ 52.9 ind, 0.25 ind/m², Centrostephanus coronatus (38.15+9.15 ind, 0.06 ind/m², Tripneustes depressus (28.68 + 6.86 ind, 0.039 ind/ m², Eucidaris thouarsii (10.66+3.37 ind, 0.025 ind/m² y Diadema mexicanum (11.75+4.92 ind, 0.023 ind/ m²; y para la clase Asteroidea: Phataria unifascialis, Mithrodia bradleyi y Acanthaster planci. Por el número de especies domina Asteroidea con 12, le siguen Echinoidea con 10 y Holothuroidea con 4.To evaluate echinoderm distribution, abundance and density a double 50 m transect, with a side observation range of 2.5 m was used at each of 11 stations (bimonthly samplings, Aug. 1997-Febr. 1998. In Bahía de Loreto the Phylum Echinodermata consists of 26 taxa. The greatest mean abundance by transect and mean densities in order of importance for Echinoidea were: Echinometra vanbrunti (94.1+ 52.9 ind, 0.25 ind/m², Centrostephanus coronatus (38.15. + 9.15 ind, 0.06 ind/m², Tripneustes depressus (28.68 + 6.86 ind, 0.039 ind/ m², Eucidaris thouarsii (10.66 + 3.37 ind, 0.025 ind/m² and Diadema mexicanum (11.75 + 4.92 ind, 0.023 ind/ m²; for Asteroidea were: Phataria unifascialis, Mithrodia bradleyi and Acanthaster planci. Asteroidea was the dominant class with 12 species, followed by Echinoidea with ten and Holothuroidea was represented by four species.
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Abundancia de Diadema antillarum (Echinodermata: Echinoidea en las costas de Venezuela
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Nicida Noriega
2006-09-01
lento incremento de las poblaciones.Abundance of Diadema antillarum (Echinodermata: Echinoidea in the coasts of Venezuela. Diadema antillarum is a shallow-water sea-urchin from the tropical Atlantic whose populations almost disappeared in 1983-84 because of widespread mortalities which reached 87-100 %. In Venezuela, urchin population densities before the mortality event were comparable to those of other Caribbean regions; however, later abundancies remain unknown. The objectives of this study were to evaluate the recent densities of certain D. antillarum populations along the Venezuelan coasts and compare the densities at the Parque Nacional Mochima before and after the mortality. At each location urchin densities were determined by means of transects using 1m²-quadrats as sampling units. The highest mean densities were observed at the sites on the central coast: Ensenada de Oricao, 0.28 ind/m² (2002 and 1.05 ind/m² (2003, and Chichiriviche de la Costa, 0.84 ind/m² (2002 and 0.74 ind/m² (2003. In Mochima, the mean density before the mortality for D. antillarum oscillated between 0.28 and 4 ind/m², after the mortality event the mean density varied between 0.15 ind/m² (2000 and 0.47 ind/m² (2000. The populations of D. antillarum studied at Parque Nacional Morrocoy and Refugio de Fauna Silvestre Cuare showed highest densities at Playuela (0.43 ind/m² and Cayo Sur (0.95 ind/m² respectively, whereas other sites showed densities below 0.1 ind/m². The density registered at Playuela in 2003 is lower than that reported before the mortality event (0.58-3.64 ind/m². The density for Parque Nacional Archipiélago de Los Roques, specifically for the Arrecife de Herradura remained constant between 2002 and 2003 with values between 0.22-0.23 ind/m² respectively. To conclude, the sea urchin abundancies observed at most of the Venezuelan coastal sites that we studied were higher than those reported for other areas of the northern Caribbean, even though the values have not
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Correlation Between Echinoidea Size and Threat Level
Bakshi, S.; Lee, A.; Heim, N.; Payne, J.
2017-12-01
Echinoidea (or sea urchins), are small, spiny, globular, animals that populate the seafloors of nearly the entire planet. Echinoidea have existed on Earth since the Ordovician period, and from their archaic origin there is much to be learned about the relationship between Echinoidea body size and how it affects the survivability of the individual. The goal of this project is to determine how Echinoidea dimensions such as body volume, area, and length compare across extinct and extant species by plotting Echinoidea data in R. We will use stratigraphic data as a source to find which species of sea urchin from our data is extinct. We will then create three sets of three histograms of the size data for each type of measurement. One set will include histograms for sea urchin length, area, and volume. The other set will include histograms for extinct sea urchin length, area, and volume. The last set will include histograms for extant sea urchin length, area, and volume. Our data showed that extant sea urchins had a larger size, and extinct sea urchins were smaller. Our length data showed that the average length of all sea urchins were 54.95791 mm, the average length of extinct sea urchins were 51.0337 mm, and the average length of extant sea urchins were 66.12774 mm. There is a generally increasing trend of size over time, except for a small outlier about 350 million years ago, where echinoderm extinction selected towards larger species and biovolume was abnormally high. Our data also showed that over the past 200 million years, echinoderm extinction selectivity drove slightly smaller sea urchins towards extinction, further supporting the idea that a larger size was and still is advantageous for echinoderms.
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Lilian Al-Chueyr Pereira Martins
1996-12-01
Full Text Available Neste artigo, o método científico de Jean-Baptiste Lamarck é estudado sob o ponto de vista de seu discurso metodológico, bem como sob o ponto de vista de sua prática científica. Essa metodologia é comparada à preconizada por Condillac, assim como à dos "ideólogos" (idéologues grupo no qual se costuma incluir o próprio Lamarck. Mostra-se que o discurso metodológico de Lamarck assemelha-se ao dos ideólogos; no entanto, sua prática científica não se coaduna com esse enfoque. Em vez de seguir uma abordagem empirista, a obra de Lamarck se fundamenta em princípios metafísicos gerais sobre a natureza. Sob o ponto de vista dos ideólogos, seu trabalho deveria ser rejeitado - o que de fato ocorreu - como um mero sistema (système metafísico - no sentido pejorativo utilizado pelos seguidores de Condillac. No entanto, o presente artigo argumenta que esse é justamente um importante e inovador aspecto da obra de Lamarck, que permitiu a eclosão do evolucionismo moderno.
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Ezhova, Olga Vladimirovna; Malakhov, Vladimir Vasil'yevich; Egorova, Ekaterina Alekseevna
2018-06-01
Studies of echinoid microscopic anatomy over the last two centuries have created a number of inaccuracies and mistakes that have accumulated in the descriptions of the intricate organization of the coelomic system of Echinoidea. To clarify the situation, we reconstructed the axial complex and radial complex of the echinoid Strongylocentrotus pallidus. The water ring is located between the perivisceral coelom and the perioral coelom. The oral haemal ring lies between the coelothelia of the water-vascular, perivisceral, and perioral rings. The axial part of the axial organ communicates with the oral haemal ring in interradius CD, but the axial coelom does not form the axocoelomic perihaemal ring. The ventral intestinal haemal vessel originates from the oral haemal ring in radius A, and then branches into a network of capillaries, from which the dorsal intestinal vessel starts. The pericardial coelom envelopes the pericardial part of the axial organ, the lacunae of which communicate with the haemocoel of the body wall and with the axial part of the axial organ. The genital haemal ring and the dorsal intestinal vessel communicate with the axial organ. The genital coelom passes in the CD interradius on the side opposite to the hindgut. There is a somatocoelomic perihaemal ring, which sends a pair of coelomic outgrowths into each radius, accompanied by a radial haemal vessel in the oral part. The mistakes and inaccuracies of early descriptions of the echinoid axial complex are listed. The axial complex and associated structures of sea urchins are compared with other eleutherozoans. © 2018 Wiley Periodicals, Inc.
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Argus Vasconcelos de Almeida
2010-01-01
Full Text Available As teorias de Lamarck e Darwin são analisadas numa amostra de livros didáticos brasileiros de biologia, num período de sessenta anos. A de Darwin ocupa, nos livros didáticos, uma área maior do que a de Lamarck. Nestes é variável a extensão do conteúdo de Lamarck. Dentre os livros, destacam-se as edições do BSCS. Nestas, pela primeira vez, é apresentado o exemplo da figura do alongamento do pescoço da girafa, para ilustrar as diferenças de abordagem entre as teorias, e reproduzido desde então na maioria dos livros didáticos. Na teoria de Darwin, o principal conceito referenciado pelos autores é o da seleção natural, e, na de Lamarck, a herança dos caracteres adquiridos. As duas teorias são diferentemente apresentadas nos livros didáticos de biologia no Brasil. Darwin é apresentado como modelo de cientista e Lamarck como um teórico especulativo, tendo a sua teoria consideravelmente deformada, distante da formulação original.Theories formulated by Lamarck and Darwin are analyzed in a sample of Brazilian textbooks on biology published in a period of sixty years. Darwin's theory is covered more than Lamarck's theory. Among the analyzed books, an important mention must be addressed for BSCS editions, since the example of the elongation of the giraffes" necks for illustrating differences between both theories is presented in this series for the first time, and since then has been adopted by the majority of other textbooks on biology. The main concepts presented as representative of Darwin's and Lamarck's theories by all textbooks are natural selection and the inheritance of acquired characters, respectively. Not only theories but also the authors are differently presented in reviewed textbooks: while Darwin is presented as a model of scientist, Lamarck appears as a speculative theoretician, his theoretical propositions being remarkably deformed and changed from their original formulations.
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Arindra Trisna Widiansyah
2016-07-01
Pantai Gatra merupakan salah satu ekowisata pantai di Kabupaten Malang yang memiliki zona pasang surut dengan substrat dominan batu. Substrat berbatu merupakan daerah yang paling padat makroorganismenya. Arthropoda dan Echinodermata mempunyai peranan penting dari segi sumber makanan maupun ekologi. Mengingat belum adanya pelaporan jenis Arthropoda dan Echinodermata di zona pasang surut Pantai Gatra, maka dilakukan penelitian inventarisasi di daerah ini. Tujuan penelitian ini adalah invetarisasi jenis Arthropoda dan Echinodermata. Hasil penelitian tentang inventarisasi jenis Arthropoda dan Echinodermata di zona pasang surut pantai Gatra Kabupaten Malang, secara keseluruhan ditemukan 14 jenis, 13 genus, dan 11 famili dari filum Arthropoda dan Echinodermata.
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Lamarck's and Darwin's theories in text books of Biology in Brazil
Almeida, Argus Vasconcelos de; Falcão, Jorge Tarcísio da Rocha
2010-01-01
As teorias de Lamarck e Darwin são analisadas numa amostra de livros didáticos brasileiros de biologia, num período de sessenta anos. A de Darwin ocupa, nos livros didáticos, uma área maior do que a de Lamarck. Nestes é variável a extensão do conteúdo de Lamarck. Dentre os livros, destacam-se as edições do BSCS. Nestas, pela primeira vez, é apresentado o exemplo da figura do alongamento do pescoço da girafa, para ilustrar as diferenças de abordagem entre as teorias, e reproduzido desde então ...
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Apodida (Echinodermata: Holothuroidea) of Thailand
DEFF Research Database (Denmark)
Mucharin, Arom
Systematics of Apodida (Echinodermata: Holothuroidea), with emphasis on Thai species was studied by means of adult morphology and anatomy, ossicle morphology, and phylogenetic analysis (COI). Over 300 Apodida specimens of Apodida were found in different parts of Thailand. The order comprises 25...... locality. The genus Synaptula was found to live in symbiosis with sponges....
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Epigenetics, Darwin, and Lamarck.
Penny, David
2015-05-29
It is not really helpful to consider modern environmental epigenetics as neo-Lamarckian; and there is no evidence that Lamarck considered the idea original to himself. We must all keep learning about inheritance, but attributing modern ideas to early researchers is not helpful, and can be misleading. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.
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As teorias de Lamarck e Darwin nos livros didáticos de Biologia no Brasil
Almeida,Argus Vasconcelos de; Falcão,Jorge Tarcísio da Rocha
2010-01-01
As teorias de Lamarck e Darwin são analisadas numa amostra de livros didáticos brasileiros de biologia, num período de sessenta anos. A de Darwin ocupa, nos livros didáticos, uma área maior do que a de Lamarck. Nestes é variável a extensão do conteúdo de Lamarck. Dentre os livros, destacam-se as edições do BSCS. Nestas, pela primeira vez, é apresentado o exemplo da figura do alongamento do pescoço da girafa, para ilustrar as diferenças de abordagem entre as teorias, e reproduzido desde então ...
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Helena Matthews-Cascon
1989-01-01
Full Text Available The genera Fasciolaria Lamarck, 1799 and Leucozonia Gray, 1847 are represented in Northeastern Brazil by three species. Fasciolaria aurantiaca Lamarck, 1816; Leucozonia ocellata (Gmelin, 1791 and Leucozonia nassa (Gmelin, 1791. The three species are described and illustrated. An identification key for all the above mentioned taxa is included, together with some ecological data. The anatomy and radula of Fasciolaria aurantiaca and Leucozonia nassa are described and illustrated. Polimorfism in Fasciolaria aurantiaca and Leucozonia nassa is discussed.
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Long, Kyle A; Nossa, Carlos W; Sewell, Mary A; Putnam, Nicholas H; Ryan, Joseph F
2016-01-01
There are five major extant groups of Echinodermata: Crinoidea (feather stars and sea lillies), Ophiuroidea (brittle stars and basket stars), Asteroidea (sea stars), Echinoidea (sea urchins, sea biscuits, and sand dollars), and Holothuroidea (sea cucumbers). These animals are known for their pentaradial symmetry as adults, unique water vascular system, mutable collagenous tissues, and endoskeletons of high magnesium calcite. To our knowledge, the only echinoderm species with a genome sequence available to date is Strongylocentrotus pupuratus (Echinoidea). The availability of additional echinoderm genome sequences is crucial for understanding the biology of these animals. Here we present assembled draft genomes of the brittle star Ophionereis fasciata, the sea star Patiriella regularis, and the sea cucumber Australostichopus mollis from Illumina sequence data with coverages of 12.5x, 22.5x, and 21.4x, respectively. These data provide a resource for mining gene superfamilies, identifying non-coding RNAs, confirming gene losses, and designing experimental constructs. They will be important comparative resources for future genomic studies in echinoderms.
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La difusión de la teoría evolucionista de Lamarck en la revista La Abeja
Camós Cabeceran, Agustí
1997-01-01
La obra de Lamarck fue difundida, entre los años 1862 y 1865, por la revista La Abeja dirigida por Antoni Bergnes de las Casas y publicada en Barcelona. En dicha revista aparece explicada la teoría evolucionista de Lamarck tanto en la traducción de su obra. Histoire naturelle des végétaux, como en una serie de artículos anónimos sobre la reproducción de los seres vivos. Estos datos pueden revelar que, en la introducción del evolucionismo en España, la teoría evolucionista de Lamarck tuvo mayo...
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La difusión de la teoría evolucionista de Lamarck en la revista La Abeja (1862-1870) de Barcelona
Camós Cabeceran, Agustí
1997-01-01
Between 1862 and 1864 Lamarck's works were diffused in Spain through a magazine called La Abeja which was edited by Antoni Bergnes de las Casas, and published in Barcelona. This may reveal a more important influence of Lamarck's theory on the introduction of evolutionary theories in Spain. La Abeja includes the translation of the Histoire naturelle des végétaux where Lamarck incorporated an early explanation of his theory of evolution; and a series of anonymous articles about the reproduction...
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Los taxones como tipos: Buffon, Cuvier y Lamarck Taxa as types: Buffon, Cuvier and Lamarck
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Gustavo Caponi
2011-03-01
Full Text Available Darwinianamente, los grupos taxonómicos son entendidos como entidades históricas que surgen en un momento de la evolución y que siempre pueden desaparecer. Pero esos grupos también fueron entendidos por muchos naturalistas como clases naturales; es decir, como tipos permanentes, a-históricos. Es mi interés señalar algunas de las formas que ese pensamiento tipológico de hecho ha tomado, subrayando que la adopción de esa perspectiva tipológica, además de no responder a compromisos teológicos, tampoco tiene porqué obedecer a la adopción de una ontología que pueda estar en conflicto con la ciencia natural. Analizaré así el modo en el que Buffon entendió las especies y el modo en los que Cuvier y Lamarck entendieron los órdenes taxonómicos superiores.From a Darwinian point of view, taxonomic groups are understood as historical entities that arise at an evolutionary moment and that can always disappear. But these groups were also understood by many naturalists as natural kinds; in other words, as permanent, ahistorical types. I will explore some of the forms that this typological thought took, showing that this typological perspective neither depends on theological beliefs, nor obeys the adoption of an ontology that might contradict natural science. Thus I shall analyze Buffon's understanding of species and the ways in which Cuvier and Lamarck understood the higher taxonomic orders.
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Rensma, Ritske
2013-04-01
Whether Jung was a Lamarckian or not has always been a hotly debated topic, both within the post-Jungian community and amongst scholars with an interest in Jung in the wider academic community. Yet surprisingly few substantial pieces of work have been dedicated to it and, to my mind, no one has yet managed to do justice to all the subtleties involved. The scholars who have claimed that Jung is a Lamarckian have, for the most part, oversimplified the debate by failing to discuss the passages in which Jung appears to be defending himself against Lamarckism; the scholars who have defended Jung against Lamarckism, however, have as a rule not adequately dealt with the question of whether these passages actually get Jung off the hook. This paper will attempt to correct this imbalance by putting forward four key passages spanning Jung's career that all represent conclusive evidence that Jung was indeed a Lamarckian. After discussing these, it will then deal in detail with the passages in which Jung appears to be defending himself against Lamarckism, making the case that they do not represent a defence against Lamarckism at all and have therefore generally been misinterpreted by many scholars. © 2013, The Society of Analytical Psychology.
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La difusión de la teoría evolucionista de Lamarck en la revista La Abeja (1862-1870) de Barcelona
Camós Cabeceran, Agustí
1997-01-01
Between 1862 and 1864 Lamarck's works were diffused in Spain through a magazine called La Abeja which was edited by Antoni Bergnes de las Casas, and published in Barcelona. This may reveal a more important influence of Lamarck's theory on the introduction of evolutionary theories in Spain. La Abeja includes the translation of the Histoire naturelle des végétaux where Lamarck incorporated an early explanation of his theory of evolution; ...
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Montgomery, E M; Hamel, J-F; Mercier, A
Egg pigmentation is proposed to serve numerous ecological, physiological, and adaptive functions in egg-laying animals. Despite the predominance and taxonomic diversity of egg layers, syntheses reviewing the putative functions and drivers of egg pigmentation have been relatively narrow in scope, centring almost exclusively on birds. Nonvertebrate and aquatic species are essentially overlooked, yet many of them produce maternally provisioned eggs in strikingly varied colours, from pale yellow to bright red or green. We explore the ways in which these colour patterns correlate with behavioural, morphological, geographic and phylogenetic variables in extant classes of Echinodermata, a phylum that has close phylogenetic ties with chordates and representatives in nearly all marine environments. Results of multivariate analyses show that intensely pigmented eggs are characteristic of pelagic or external development whereas pale eggs are commonly brooded internally. Of the five egg colours catalogued, orange and yellow are the most common. Yellow eggs are a primitive character, associated with all types of development (predominant in internal brooders), whereas green eggs are always pelagic, occur in the most derived orders of each class and are restricted to the Indo-Pacific Ocean. Orange eggs are geographically ubiquitous and may represent a 'universal' egg pigment that functions well under a diversity of environmental conditions. Finally, green occurs chiefly in the classes Holothuroidea and Ophiuroidea, orange in Asteroidea, yellow in Echinoidea, and brown in Holothuroidea. By examining an unprecedented combination of egg colours/intensities and reproductive strategies, this phylum-wide study sheds new light on the role and drivers of egg pigmentation, drawing parallels with theories developed from the study of more derived vertebrate taxa. The primary use of pigments (of any colour) to protect externally developing eggs from oxidative damage and predation is
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Discussion of evolution between neo-lamarckism and neo-darwinism in the Czech lands, 1900-1915
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Hermann, Tomáš; Šimůnek, Michal V.
2010-01-01
Roč. 32, č. 3 (2010), s. 283-300 ISSN 1210-0250 R&D Projects: GA ČR GPP410/10/P550 Institutional research plan: CEZ:AV0Z80630520 Keywords : neo-lamarckism * neo- darwinism * history of biology Subject RIV: AB - History
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An occurence records database of Irregular Echinoids (Echinodermata: Echinoidea) in Mexico.
Martínez-Melo, Alejandra; Solís-Marín, Francisco Alonso; Buitrón-Sánchez, Blanca Estela; Laguarda-Figueras, Alfredo
2016-01-01
Research on echinoderms in Mexico began in the late nineteenth century. We present a dataset that includes the taxonomic and geographic information of irregular echinoids from Mexico, housed in four collections: 1) Colección Nacional de Equinodermos "Ma. Elena Caso Muñoz" from the Instituto de Ciencias del Mar y Limnología (ICML), Universidad Nacional Autónoma de México (UNAM); 2) Invertebrate Zoology Collection, Smithsonian Museum of Natural History, Washington, D.C., United States of America (USA); 3) Invertebrate Collection, Museum of Comparative Zoology, University of Harvard, Boston, Massachusetts, USA and 4) Invertebrate Zoology, Peabody Museum, Yale University, New Haven, Connecticut, USA. A total of six orders, 17 families, 35 genera and 68 species are reported, 37 distributed in the Pacific coast and 31 in the Atlantic coast, none of them was found in both coasts. The most diverse region is the Gulf of California (S=32); the most diverse order is Spatangoida with 31 species reported in mexican waters.
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Francisco Alonso Solís-Marín
2012-10-01
Full Text Available Enypniastes eximia Théel, 1882 (Echinodermata: Holothuroidea a swimming sea cucumber is reported for the first time from Peru. The species was collected in the Continental rise (563-1,201 m off Trujillo Department. Reference material has been deposited in the Coleccion Cientifica del Instituto del Mar del Peru (IMARPE, Lima, Peru.
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Sutherby Josh
2012-04-01
Full Text Available Abstract Background A metamorphic life-history is present in the majority of animal phyla. This developmental mode is particularly prominent among marine invertebrates with a bentho-planktonic life cycle, where a pelagic larval form transforms into a benthic adult. Metamorphic competence (the stage at which a larva is capable to undergo the metamorphic transformation and settlement is an important adaptation both ecologically and physiologically. The competence period maintains the larval state until suitable settlement sites are encountered, at which point the larvae settle in response to settlement cues. The mechanistic basis for metamorphosis (the morphogenetic transition from a larva to a juvenile including settlement, i.e. the molecular and cellular processes underlying metamorphosis in marine invertebrate species, is poorly understood. Histamine (HA, a neurotransmitter used for various physiological and developmental functions among animals, has a critical role in sea urchin fertilization and in the induction of metamorphosis. Here we test the premise that HA functions as a developmental modulator of metamorphic competence in the sea urchin Strongylocentrotus purpuratus. Results Our results provide strong evidence that HA leads to the acquisition of metamorphic competence in S. purpuratus larvae. Pharmacological analysis of several HA receptor antagonists and an inhibitor of HA synthesis indicates a function of HA in metamorphic competence as well as programmed cell death (PCD during arm retraction. Furthermore we identified an extensive network of histaminergic neurons in pre-metamorphic and metamorphically competent larvae. Analysis of this network throughout larval development indicates that the maturation of specific neuronal clusters correlates with the acquisition of metamorphic competence. Moreover, histamine receptor antagonist treatment leads to the induction of caspase mediated apoptosis in competent larvae. Conclusions We conclude that HA is a modulator of metamorphic competence in S. purpuratus development and hypothesize that HA may have played an important role in the evolution of settlement strategies in echinoids. Our findings provide novel insights into the evolution of HA signalling and its function in one of the most important and widespread life history transitions in the animal kingdom - metamorphosis.
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Primer registro de Florometra magellanica (Bell, 1882 (Echinodermata: Crinoidea para el Perú
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Elba Prieto Rios
2011-08-01
Full Text Available Se registra por primera vez para el Perú al Crinoideo (Echinodermata Florometra magellanica (Bell, 1882. La especie fue recolectada en el talud continental (360 – 814 m frente al departamento de Piura al norte del Perú (3°38,67’S, 81° 2,73’W. El material de referencia se encuentra depositado en la Colección Científica del Instituto del mar del Perú (IMARPE, Lima, Perú y en la Colección Nacional de Equinodermos de la Universidad Nacional Autónoma de México, Ciudad de México.
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Mechanisms of adaptive evolution. Darwinism and Lamarckism restated.
Aboitiz, F
1992-07-01
This article discusses the conceptual basis of the different mechanisms of adaptive evolution. It is argued that only two such mechanisms may conceivably exist, Lamarckism and Darwinism. Darwinism is the fundamental process generating the diversity of species. Some aspects of the gene-centered approach to Darwinism are questioned, since they do not account for the generation of biological diversity. Diversity in biological design must be explained in relation to the diversity of interactions of organisms (or other higher-level units) with their environment. This aspect is usually overlooked in gene-centered views of evolution. A variant of the gene-selectionist approach has been proposed to account for the spread of cultural traits in human societies. Alternatively, I argue that social evolution is rather driven by what I call pseudo-Lamarckian inheritance. Finally, I argue that Lamarckian and pseudo-Lamarckian inheritance are just special cases of faithful replication which are found in the development of some higher-order units, such as multicellular organisms and human societies.
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Francisco Alonso Solís-Marín
2013-06-01
Full Text Available Se registra por primera vez para el Perú la especie de pepino de mar Heterocucumis godeffroyi(Semper, 1868 (Echinodermata: Holothuroidea. La especie fue recolectada a 19 m de profundidad en Pucusana, de-partamento de Lima. Este registro representa el límite más norteño de distribución de la especie reconocido hasta el momento. Material de referencia se encuentra depositado en la Colección de Zoología Acuática, del Laboratorio de Biología Marina, Departamento de Ciencias Biológicas y Fisiológicas, Universidad Peruana Cayetano Heredia, Lima, Perú.
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Eduardo J.B. Lima
2009-03-01
Full Text Available The edible sea urchin Echinometra lucunter (Linnaeus, 1758 is a very common species on the sublittoral-midlittoral in Brazilian rocky shores. The aim of this work was to describe the gametogenesis and reproductive strategy of the E. lucunter population at Muro Alto beach in the Northeast coast of Brazil from August 2004 to August 2005. A total of 240 specimens were collected on the sandstone reef flat from a tidepool during spring low tides. The overall sex ratio was1.12:1,withoutsignificanttemporalvariationexceptinOctober2004. Firsts sexual maturity ocurred in individuals from a diameter of 20.8 mm. There was not a significant difference in gonad index between females and males during the sampling period. The female's gonad index variation was associated with a well-defined spawning, corroborated by the histological analysis of the gonads, which demonstrates sex differences of the gamete production. By contrast, the males showed no clear pattern. It is suggested that continuous reproduction with seasonal peaks in the E. lucunter population occurs at Muro Alto beach.O ouriço-do-mar comestível Echinometra lucunter (Linnaeus, 1758 é uma espécie muito comum no infralitoral e mediolitoral do Brasil. O objetivo deste trabalho foi descrever a gametogênese e a estratégia reprodutiva da população de E. lucunterna praia de Muro Alto entre agosto de 2004 e agosto de 2005. Um total de 240 espécimes foi capturado de uma poça de maré situada no topo recifal, durante as marés baixas de sizígia. A razão sexual total foi de 1,12:1 sem variação temporal significativa, exceto em outubro de 2004. A primeira maturidade sexual ocorreu em indivíduos a partir de 20,8 mm de diâmetro. Não houve nenhuma diferença significativa no índice gonadal entre fêmeas e machos durante o período de amostragem. A variação do índice gonadal das fêmeas foi associada a um período de desova bem definido, corroborado pela análise histológica das gônadas, que demonstra diferenças sexuais na produção de gametas. Ao contrário, os machos não apresentaram nenhum padrão. Sugere-se que a reprodução da população de E. lucunter na praia de Muro Alto é contínua, compicos sazonais.
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On Pomacea canaliculata (Lamarck, 1822 (Mollusca; Pilidae: Ampullariidae
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Silvana C. Thiengo
1993-03-01
Full Text Available This paper deals with the morphology of Pomacea caniculata (Lamarck, 1822 collected at Corrientes, Argentina. Comparison is made with Pomacea lineata (Spix, 1827 and Pomacea sordida (Swainson, 1823. The shell is globose, heavy, with greenish or horn-colored periostracum and dark spiral bands; apex subelevated, 5-6 whorls increasing rather rapidly and separated by very deep suture. Aperture large, rounded to subelongated; lip sometimes reddish; umbilicus large and deep; operculum corneous, entirely closing the aperture. Ratios: shell width/shell length = 0.78-0.96 (mean 0.86; aperture length/shell length = 0.68-0.77 (mean 0.72. Radula similar to other congeneric species. Testis and spermiduct as in P. lineata and P. sordida; prostate cylindric and short, cream in color as the testis. Penial sheath straight bearing a central outer gland deeply embedded in the tissue of its basal portion and a large wrinkled gland occupying 2/3 of the distal tip of its inner surface; the rigth margin of the sheath overlaps the left one until 2/3 of its proximal end. Female reproductive apparatus similar to that P. lineata; vestigial male copulatory apparatus (penis and its sheath present in all females examined.
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Retorno a Limoges. La Adaptación en Lamarck
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Caponi, Gustavo
2006-06-01
Full Text Available In this article I will be analyzing the Darwinist paradigm in the biological science, discussing its capacity to give satisfactory understanding of the new data from biochemistry, microbiology and genetics. The general aim of this analysis is to contribute for the debate about the statute of the scientific theories. Its specific aim is to reflect upon a possible crisis of the Darwinist paradigm, which could corroborate the conception of scientific theories as something historically transitory, and not as definitive discoveries.
Contrariando las lecturas post-darwinianas de Lamarck, Camille Limoges nos dio algunas claves que, debidamente reconsideradas, nos permiten afirmar que, para el autor de la Filosofía Zoológica, las modificaciones de los perfiles orgánicos producidas por las circunstancias no eran nada semejante a lo que hoy caracterizaríamos como respuestas a las exigencias del medio. Las mismas eran simples trasformaciones producidas por procesos fisiológicos que modelaban lo viviente con total independencia del carácter favorable o desfavorable que pudiesen revestir las modificaciones producidas. -
Tres nuevos registros de asteroideos (Echinodermata: Asteroidea de Perú
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Yuri Hooker
2012-02-01
Full Text Available En el presente trabajo se registran 3 nuevos asteroideos (Echinodermata: Asteroidea de aguas someras (4 - >50 m para el Perú: Astropecten regalis Gray, 1840, Paulia horrida Gray 1840 y Meyenaster gelatinosus (Meyen, 1834. Astropecten regalis se conocía desde el Golfo de California hasta Panamá, en el presente trabajo, se amplía su distribución hasta Máncora, Perú. La distribución geográfica de Paulia horrida era conocida desde Baja California, hasta Isla Cocos, Costa Rica, en este estudio se amplía su distribución geográfica hasta Punta Sal, Perú. A Meyenaster gelatinosus se le conocía solo de Chile, en el presente trabajo se registra y confirma su presencia en el Perú, ampliando su distribución norte hasta San Juan de Marcona. Se proporciona información morfológica de las especies, características del hábitat y fotografías in situ y de los especímenes recién recolectados.
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Kropotkin between Lamarck and Darwin: the impossible synthesis
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Girón, Álvaro
2003-06-01
Full Text Available Prince P.A. Kropotkin (1842-1921 was the most important leader of revolutionary anarchism of his generation. He was also a respected explorer, geographer, and wrote a variety of books on the French Revolution, prison systems and Russian literature. However, he is better known for his contribution to the debate on Social Darwinism, exemplified by his book Mutual Aid. A Factor Evolution (1902. Actually, Kropotkin was trying to build his own brand of evolutionary Ethics: a complete socio-biology consistent with revolutionary goals. But there was a serious obstacle. The presence of the Malthusian population laws at the very core of Darwinism blocked any potential progress in this direction. Kropotkin tried to extirpate the Malthusian sting by making a critical analysis of natural selection and proposing a synthesis between Lamarck and Darwin in the 1910s.
The aim of this article is to study the basics of the argument deployed by Kropotkin. It has been paid especial attention to the criticisms addressed to the hard heredity theory of August Weismann, and the reasons why Kropotkin’s contribution in this field has been ignored.
El príncipe P.A. Kropotkin (1842-1921 fue el líder mas importante del anarquismo revolucionario de su generación. El fue también un respetado explorador y geógrafo, y escribió una variada serie de libros sobre la revolución francesa, el sistema de prisiones o la literatura rusa. Sin embargo, el es más conocido por su contribución al debate sobre el Darwinismo Social, ejemplificada por su libro El apoyo mutuo. Un factor de la evolución (1902. En realidad, Kropotkin estaba tratando de construir su particular versión de la ética evolucionista: una acabada sociobiología consistente con los objetivos revolucionarios. Pero existía un serio obstáculo. La presencia de las leyes de la población maltusianas en el mismo corazón del darwinismo bloqueaban cualquier tipo de progreso en esa dirección. Kropotkin -
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R. HOFFMAN
2015-03-01
Full Text Available Global climate change is causing the Mediterranean coastal area of Israel to gradually acquire tropical characteristics. Rising sea surface temperatures in the eastern Mediterranean basin have facilitated the introduction, settlement and establishment of hundreds of alien species (Zenetos et al. 2012. The vast majority of these exotic species are of Indo-Pacific origin. We report the occurrence of the genus Dichotomaria in the eastern Mediterranean on the basis of specimens identified as Dichotomaria cf. obtusata (J. Ellis & Solander Lamarck. Tetrasporophytes with sporangial initials were identified morphologically and confirmed molecularly using plastid rbcL sequences. We also discuss possible paths of introduction of this and other alien species into the Levantine Sea.
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Eliana de Fátima Marques de Mesquita
1990-01-01
Full Text Available In this paper the authors give an anatomical and histological analysis of the male reproductive system of Pomacea canaliculata (Lamarck, 1822. Anatomically, the testis is better evidentiated than the ovary. In the structure of the testis a great number of very small channels converges to a single one. The male copulatory organs result of transformations that take place in the inner surface on the palial membrane. Histologically, the testis of immature males shows seminiferous ducts with round egg-shaped forms. In their lumens we could notice masses of cells that will originate spermatozoids. The penis has a conjunctive muscular sheath that can be seen in van Gieson's coloured preparations.
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Fátima L. F. Mariante
2009-12-01
Full Text Available Echinometra lucunter Linnaeus, 1758 is a tropical sea urchin with strong bioerosive potential. Consequently, this species has great ecological importance. The species occurs in high densities along the Brazilian coast, particularly in the south and southeast. The objective of this work was to evaluate both the effects of annual seasonality and the lunar cycle on the reproduction of E. lucunter. Individuals were sampled monthly for a period of one year and during four complete lunar cycles. The gonadosomatic index (GI was calculated to determine the annual and monthly reproductive peaks based on the lunar phase. The sex ratio (male:female was 1:1.04, without significant difference in sexual proportion. The GI was significantly higher for males than for females. The first sexual maturation occurs when carapace width reaches 23.30 mm, and 50% of the animals have gonads with 28.22 mm. The spawning peak generally occurs during the whole year from the full moon to the waning moon. However, there is an annual reproductive peak from summer to autumn.
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Global diversity and phylogeny of the Asteroidea (Echinodermata.
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Christopher L Mah
Full Text Available Members of the Asteroidea (phylum Echinodermata, popularly known as starfish or sea stars, are ecologically important and diverse members of marine ecosystems in all of the world's oceans. We present a comprehensive overview of diversity and phylogeny as they have figured into the evolution of the Asteroidea from Paleozoic to the living fauna. Living post-Paleozoic asteroids, the Neoasteroidea, are morphologically separate from those in the Paleozoic. Early Paleozoic asteroid faunas were diverse and displayed morphology that foreshadowed later living taxa. Preservation presents significant difficulties, but fossil occurrence and current accounts suggests a diverse Paleozoic fauna, which underwent extinction around the Permian-Triassic interval was followed by re-diversification of at least one surviving lineage. Ongoing phylogenetic classification debates include the status of the Paxillosida and the Concentricycloidea. Fossil and molecular evidence has been and continues to be part of the ongoing evolution of asteroid phylogenetic research. The modern lineages of asteroids include the Valvatacea, the Forcipulatacea, the Spinlosida, and the Velatida. We present an overview of diversity in these taxa, as well as brief notes on broader significance, ecology, and functional morphology of each. Although much asteroid taxonomy is stable, many new taxa remain to be discovered with many new species currently awaiting description. The Goniasteridae is currently one of the most diverse families within the Asteroidea. New data from molecular phylogenetics and the advent of global biodiversity databases, such as the World Asteroidea Database (http://www.marinespecies.org/Asteroidea/ present important new springboards for understanding the global biodiversity and evolution of asteroids.
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Nobre, C R; Santana, M F M; Maluf, A; Cortez, F S; Cesar, A; Pereira, C D S; Turra, A
2015-03-15
Apart from the physiological impacts on marine organisms caused by ingesting microplastics, the toxicity caused by substances leaching from these particles into the environment requires investigation. To understand this potential risk, we evaluated the toxicity of virgin (raw) and beach-stranded plastic pellets to the development of embryos of Lytechinus variegatus, simulating transfers of chemical compounds to interstitial water and water column by assays of pellet-water interface and elutriate, respectively. Both assays showed that virgin pellets had toxic effects, increasing anomalous embryonic development by 58.1% and 66.5%, respectively. The toxicity of stranded pellets was lower than virgin pellets, and was observed only for pellet-water interface assay. These results show that (i) plastic pellets act as a vector of pollutants, especially for plastic additives found on virgin particles; and that (ii) the toxicity of leached chemicals from pellets depends on the exposure pathway and on the environmental compartment in which pellets accumulate. Copyright © 2015 Elsevier Ltd. All rights reserved.
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M. Aminur Rahman
2012-01-01
Full Text Available Salmacis sphaeroides (Linnaeus, 1758 is one of the regular echinoids, occuring in the warm Indo-West Pacific, including Johor Straits, between Malaysia and Singapore. In order to investigate the developmental basis of morphological changes in embryos and larvae, we documented the ontogeny of S. sphaeroides in laboratory condition. Gametes were obtained from adult individuals by 0.5 M KCl injection into the coelomic cavity. Fertilization rate at limited sperm concentration (10−5 dilution was 96.6±1.4% and the resulting embryos were reared at 24°C. First cleavage (2-cell, 4-cell, 8-cell, 16-cell, 32-cell, and multicell (Morulla stages were achieved 01.12, 02.03, 02.28, 02.51, 03.12, and 03.32 h postfertilization. Ciliated blastulae with a mean length of 174.72±4.43 μm hatched 08.45 h after sperm entry. The gastrulae formed 16.15 h postfertilization and the archenteron elongated constantly while ectodermal red-pigmented cells migrated synchronously to the apical plate. Pluteus larva started to feed unicellular algae in 2 d, grew continuously, and finally attained metamorphic competence in 35 d after fertilization. Metamorphosis took approximately 1 h 30 min from attachment to the complete resorption of larval tissues and the development of complete juvenile structure with adult spines, extended tubefeet and well-developed pedicellaria, the whole event of which usually took place within 1 d postsettlement. This study represents the first successful investigation on embryonic, larval, and early juvenile development of S. sphaeroides. The findings would greatly be helpful towards the understanding of ontogeny and life-history strategies, which will facilitate us to develop the breeding, seed production, and culture techniques of sea urchins in captive condition.
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Alexandra Mara Cruz Lage
2011-07-01
Full Text Available Este estudo avaliou as características reprodutivas de uma população do ouriço do mar Lytechinus variegatus e a influência do ciclo lunar na liberação de gametas. Foram realizadas oito coletas para avaliação do índice gonadossomático (IG e dos parâmetros populacionais relacionados com a reprodução. Para avaliação do efeito da Lua na liberação de gametas foram realizadas coletas em três ciclos lunares completos. Ao todo foram coletados 295 indivíduos, sendo 156 machos e 131 fêmeas (proporção 1,19:1, porém não houve diferença significativa na proporção sexual da população. O peso dos machos foisignificativamente maior que o das fêmeas, porém não houve diferença significativa no IG, peso gonadal e diâmetro entre os sexos. Com a amplitude no diâmetro dos animais coletados (5,5-8,7 cm foram estabelecidas cinco classes de tamanho. Não houve diferençassignificativas no IG entre as classes de tamanho. Houve efeito da periodicidade lunar na liberação de gametas, com menor IG na lua nova, indicando que esta ocorre no primeiro quarto lunar e em marés de sizígia.This work evaluated the spawning of sea urchin Lytechinus variegates based on lunar cycle and population characteristics. Eight monthly collections were realized to estimate the gonadosomatic index (GI and population parameters regarding reproduction. To evaluate the effect of the lunar cycle on spawning, samples were taken for each moon phase of three lunar cycles. In the entire work 295 individuals were collected, 156 males and 131 females (1.19:1 ratio. However, there was no significant difference in the sex ratio of the population. The weight of males was significantly greater than that of females. There were no differences between males and females in gonadosomatic index (GI, gonad weight and diameter. There was aneffect of the lunar periodicity on spawning, with lower GI in new moon, indicating that spawning occurs on the first lunar quarter in spring tide.
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Lamarck needs Darwin: the search for purpose in the study of evolution and of history
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Moreno, Juan
2009-12-01
Full Text Available Lamarck´s theory of the inheritance of acquired characteristics and immediate responses to environmental challenges has offered a promise of protagonism of human beings and their fellow trvellers, the other organisms, in the evolutionary process. Darwin’s theory about evolution by natural selection does not offer this consolation and does not presuppose anything else other than gradual cahnges in the composition of natural populations. The study of ecology, ethology, neurobiology, animal culture, psichology and human history reveals that the lamarckian interpretations of change and character transmission processes always assume what they intend to explain, that is previous processes of darwinian evolution that guarantee the adaptive nature of the observed responses. The permanent search of direction and intentionality in evolutionary processes by many scientists suggests the limited acceptance of materilaistic explanations as those offered by Darwin’s theory.
a teoría de Lamarck sobre herencia de caracteres adquiridos y sobre respuestas inmediatas a retos ambientales ha ofrecido una promesa de intencionalidad y protagonismo en el proceso evolutivo al ser humano y a los restantes organismos. La teoría de Darwin sobre evolución por selección natural no ofrece este consuelo y no presupone nada más que procesos de recambio gradual en poblaciones naturales. El estudio de la ecología, la etología, la neurobiología, la cultura animal, la psicología y la historia humana revela que las interpretaciones lamarckianas de los cambios y procesos de transmisión de caracteres presuponen siempre lo que pretenden explicar, es decir procesos previos de evolución darwiniana que garantizan la naturaleza adaptativa de las respuestas observadas. La búsqueda continua de dirección y de intención en los procesos evolutivos por muchos científicos sugiere la escasa aceptación de explicaciones materialistas como las que ofrece la teoría de
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AI Gondim
Full Text Available The genus Diadema presently consists of seven species, two of which are known from the Brazilian coast: D. antillarum and D. ascensionis. The first is usually known for shallow coastal areas, while the second was apparently restricted to oceanic islands. In February 2011, a dense population of D. ascensionis was observed on the coastal reefs of Praia do Francês (Alagoas State, northeastern Brazil. Five specimens were collected and transported to the laboratory where morphological studies of the test and pedicellariae were conducted. Subsequently, visits were made to scientific collections in order to compare and confirm species identifications. Our observations confirm the presence of tridentate pedicellariae with narrow and strongly curved valves. The axial cavity in the tips of the spines is filled with dense nonreticular tissue. This taxonomic data confirms the occurrence of D. ascensionis in coastal areas. On the coastal reefs of Praia do Francês, animals were observed from the beach to the reef formations about 200 m offshore in areas with a sandy substrate and in reef cavities, usually in clear and well illuminated waters. Solitary individuals or groups of up to 15 individuals formed dense populations in the area. We stress the importance of pedicellariae for the specific identification of the Diadematidae, considering that they are quite constant and reliable at this taxonomic level. Our results demonstrate that D. ascensionis is not restricted to insular environments and that this species may be common in shallow coastal habitats.
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Mueller Susanne
2008-07-01
Full Text Available Abstract Background Traditional comparative morphological analyses and subsequent three-dimensional reconstructions suffer from a number of drawbacks. This is particularly evident in the case of soft tissue studies that are technically demanding, time-consuming, and often prone to produce artefacts. These problems can partly be overcome by employing non-invasive, destruction-free imaging techniques, in particular micro-computed tomography or magnetic resonance imaging. Results Here, we employed high-field magnetic resonance imaging techniques to gather numerous data from members of a major marine invertebrate taxon, the sea urchins (Echinoidea. For this model study, 13 of the 14 currently recognized high-ranking subtaxa (orders of this group of animals were analyzed. Based on the acquired datasets, interactive three-dimensional models were assembled. Our analyses reveal that selected soft tissue characters can even be used for phylogenetic inferences in sea urchins, as exemplified by differences in the size and shape of the gastric caecum found in the Irregularia. Conclusion The main focus of our investigation was to explore the possibility to systematically visualize the internal anatomy of echinoids obtained from various museum collections. We show that, in contrast to classical preparative procedures, magnetic resonance imaging can give rapid, destruction-free access to morphological data from numerous specimens, thus extending the range of techniques available for comparative studies of invertebrate morphology.
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Marcelo Gentil Avila
1996-01-01
Full Text Available The specimens of Arenaeus cribrarius (Lamarck, 1818 used in this study were collected in the locality of Barra da Lagoa beach, Florianópolis, Santa Catarina, Brazil, in the period of April/1991 to March/1992. In this area temperature and salinity values were observed. A total of 341 samples, that 184 were male and 157 were female were collectted. The maturacion sexual stadium were measured (cm and weightied (g. Expression of relation among weight of body (wt and width of carapace (wid was Wt=0,0567 Wid3,0494 on males and wt=0,074 Wid2,8795 on females. The relation length (Lt width (wid of carapace was Lt=0,4322. wid on males and Lt=0,4578. wid on females.
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Spicule size variation in Xestospongia testudinaria Lamarck, 1815 at Probolinggo-Situbondo coastal
Subagio, Iwenda Bella; Setiawan, Edwin; Hariyanto, Sucipto; Irawan, Bambang
2017-06-01
Xestospongia testudinaria Lamarck, 1815 is a marine sponge that become a main constituent in reef ecosystems at northern waters Probolinggo-Situbondo. This barrel sponge species possesses an oxea type of spicule that varies in dimensions (length and width) in concordance to condition and location of habitat. The experiment aimed to understand how spicules condition of this sponge reacted to environment variables. Sponges' specimen were taken by SCUBA equipment in 6-7 m, 10-11 m, and 14-15 m depths in addition to four different localities and three different part of sponges' body (upper, middle and basal parts). Environmental variables data were also retrieved (salinity, water clarity, temperature, dissolve silica, and depth) in each locations. Results confirmed that oxea spicule size either in length or width dimensions in four locations (Batu Lawang coral cluster [BL], Karang Mayit coral cluster [KM], Paiton coral cluster [PT], and Takat Palapa [TP]) relatively increased toward depth. Likewise, the size of spicules in the TP relatively longer than three other locations. In contrast, spicules oxea in PT relatively wider than three other locations. Salinity gave negative impact to spicules length, while depth gave positive impact. Depth, water clarity, dissolve silica, and temperature gave negative effect to spicules width while salinity gave positive impact.
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Lamarck necesita a Darwin: la búsqueda de intención en el estudio de la evolución y de la historia
Moreno, Juan
2009-01-01
a teoría de Lamarck sobre herencia de caracteres adquiridos y sobre respuestas inmediatas a retos ambientales ha ofrecido una promesa de intencionalidad y protagonismo en el proceso evolutivo al ser humano y a los restantes organismos. La teoría de Darwin sobre evolución por selección natural no ofrece este consuelo y no presupone nada más que procesos de recambio gradual en poblaciones naturales. El estudio de la ecología, la etología, la neurobiología, la cultura animal, la psicología y la ...
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Glover, Adrian G; Wiklund, Helena; Rabone, Muriel; Amon, Diva J; Smith, Craig R; O'Hara, Tim; Mah, Christopher L; Dahlgren, Thomas G
2016-01-01
We present data from a DNA taxonomy register of the abyssal benthic Echinodermata collected as part of the Abyssal Baseline (ABYSSLINE) environmental survey cruise 'AB01' to the UK Seabed Resources Ltd (UKSRL) polymetallic-nodule exploration claim 'UK-1' in the eastern Clarion-Clipperton Zone (CCZ), central Pacific Ocean abyssal plain. Morphological and genetic data are presented for 17 species (4 Asteroidea, 4 Crinoidea, 2 Holothuroidea and 7 Ophiuroidea) identified by a combination of morphological and genetic data. No taxa matched previously published genetic sequences, but 8 taxa could be assigned to previously-described species based on morphology, although here we have used a precautionary approach in taxon assignments to avoid over-estimating species ranges. The Clarion-Clipperton Zone is a region undergoing intense exploration for potential deep-sea mineral extraction. We present these data to facilitate future taxonomic and environmental impact study by making both data and voucher materials available through curated and accessible biological collections.
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Bedford, A. P.; Moore, P. G.
1985-01-01
Psammechinus miliaris occurs in the Clyde Sea area in large numbers (diet of rotting weed but not on fresh weed. Large seasonal variation existed, however, with fast growth occurring in June-August and little, or no, growth in December-February, irrespective of diet. Starved controls did not grow. Correcting for seasonality, rotting kelp still promoted faster growth of young urchins than did fresh weed. Larger (older) individuals showed no difference. Urchins fed fresh weed had significantly longer gut retention times. Protein absorption efficiency was higher on fresh than rotting weed, varying with weed protein content and size of urchin. Very young individuals can only digest high protein weed efficiently, eg. material derived from near the frond meristem. Organic carbon content of rotting weed was significantly lower than fresh weed. Carbon absorption efficiencies were significantly higher on fresh weed which related to organic carbon content. Standard-sized urchins fed rotting weed produced larger dry weights of faeces per day, reflecting increased ingestion rate. In closed-system choice experiments urchins preferred rotting weed kinetically. Size-frequency analysis of field populations suggested that weed beds are principally colonized by larval settlement from the plankton. Mature Psammechinus have evolved different 'strategies' for exploiting fresh and rotting weed. Fresh weed is relatively difficult to digest and long gut retention times allow high protein absorption efficiencies to be attained. Rotting weed has microbial protein in quantities and a lower organic carbon fraction. Some bacterial protein is seemingly unavailable though and lower protein absorption efficiencies result. Thus gut retention time is shortened and more food passed through the gut. Growth remains equivalent. Substratum digestion is of paramount importance for Psammechinus feeding on either fresh or rotting weed, cf. the 'classical' microbe-stripping detritivore of Fenchel.
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José Carlos Hernández
2006-12-01
Full Text Available Diadema antillarum Philippi occurs in high density populations in the Canary Islands, creating extensive barren areas. During one year we determined seasonal changes in the algal abundance and population densities, test diameter, gut contents and gonad index of sea urchins in two localities (Abades and Boca Cangrejo. Boca Cangrejo shows higher algae cover and species richness than Abades. The sea urchin population at Abades had a higher density and smaller urchins than Boca Cangrejo. Boca Cangrejo sea urchins showed higher specific richness in gut contents than Abades urchins. The sea urchin population at Abades did not have a clearer reproductive periodicity or higher gonad index than the Boca Cangrejo population. Temporal and spatial changes in gonad periodicity of Diadema antillarum are attributed, at least in part, to benthic food availability (algal cover and algal species number and intra-specific competition.
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Martinez, Mariano I.; Penchaszadeh, Pablo E.
2017-12-01
This paper describes a new species of Psolus (Holothuroidea, Echinodermata), P. lawrencei sp. nov., (19 specimens) found in the deep sea (308-1398 m) in the Southwestern Atlantic Ocean (SWAO) (around 38°S-54°W) with brooders (up to 3.15 mm) in the tentacles of females and a penis-like genital papilla on males. The presence of dorsal scales, the concave shape of the ossicles with a bridge, the distribution of podia on the dorsal side and the absence of large and conspicuous oral and anal valves are unique for this species. Furthermore, this is the first species of this genus found outside Antarctica that broods between its tentacles. The paper also reviews the reproductive, brooding development and morphological characteristics of P. lawrencei sp. nov. and compares them with those of several members of the family Psolidae. Finally, a possible connectivity between the deep-sea populations in the SWAO and in Antarctica is considered based on the appearance of a similar reproductive pattern in populations found in both areas, which suggests a past or present connection between these regions.
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Volpi Ghirardini, A; Arizzi Novelli, A; Tagliapietra, D
2005-09-01
The capacity of two toxicity bioassays (fertilization and embryo toxicity tests) to discriminate sediment toxicity using the sea urchin Paracentrotus lividus was tested in five stations with different levels of pollution in the Lagoon of Venice. Two stations were located in estuarine sites, two in the industrial zone, and one in a site at the top of our quality gradient (reference). Elutriate was chosen as sediment matrix to assess the potential effects of bioavailable pollutants in the water column as a consequence of sediment resuspension (dredging and dumping, fishing gear, etc.). An experimental design based on Quality Assurance/Quality Control procedures (QA/QC) was adopted in order to set the methodological basis for an effective use of these bioassays in monitoring programs. Results revealed both higher embriotoxicity than spermiotoxicity in all stations and the efficacy of combined use of both toxicity bioassays in discriminating differing pollution/bioavailability between stations and periods. The good representativeness of the integrated sampling scheme and the standardization of all experimental phases yielded high precision of results. Clear Toxicity Fingerprints were evidenced for the investigated sites through the combined use of both bioassays. A good fit between ecotoxicological data and chemical contamination levels was found, except for unnatural sediment texture.
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Almaça, Carlos
2000-12-01
Full Text Available
Darwinism was championed in Portugal by the University and progressionist political parties from the 1860's on. Neo-Darwinism was neglected in its proper time and so the acceptance of the inheritance of acquired characters continued over the first decades of the 20th century. Men of medical education who were professors of Biology at the University of Oporto supported neo-Lamarckian theories in early 20th century. The first one has been Américo Pires de Lima (1886-1966, professor of Botany, whose doctoral dissertation sustaining early Darwinism and neo-Lamarckism was presented in 1912. This thesis, as well as a few neo-Lamarckian publications with antropological significance, are commented and discussed in the present paper.
El Darwinismo fue defendido en Portugal en la Universidad y por los partidos políticos progresistas durante la década de los años 60 del siglo XIX. El neo-darwinismo fue ignorado en su tiempo y así continuó la aceptación de la herencia de los caracteres adquiridos a lo largo de las primeras décadas del siglo XX. Los profesores de biolog
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Naughton, K M; O'Hara, T D; Appleton, B; Cisternas, P A
2014-09-01
In this paper we examine the phylogeny and biogeography of the temperate genera of the Ophiocomidae (Echinodermata: Ophiuroidea) which have an interesting asymmetrical anti-tropical distribution, with two genera (Ophiocomina and Ophiopteris) previously considered to have a separate species in both the North and South hemispheres, and the third (Clarkcoma) diversifying in the southern Australian/New Zealand region. Our phylogeny, generated from one mitochondrial and two nuclear markers, revealed that Ophiopteris is sister to a mixed Ophiocomina/Clarkcoma clade. Ophiocomina was polyphyletic, with O. nigra and an undescribed species from the South Atlantic Ocean sister to a clade including Clarkcoma species and O. australis. The phylogeny also revealed a number of recently diverged lineages occurring within Clarkcoma, some of which are considered to be cryptic species due to the similarity in morphology combined with the apparent absence of interbreeding in a sympatric distribution, while the status of others is less certain. The phylogeny provides support for two transequatorial events in the group under study. A molecular clock analysis places both events in the middle to late Miocene. The analysis excludes a tectonic vicariance hypothesis for the antitropical distribution associated with the breakup of Pangaea and also excludes the hypothesis of more recent gene flow associated with Plio/Pleistocene glacial cycling. Copyright © 2014 Elsevier Inc. All rights reserved.
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Prie V.
2012-07-01
Full Text Available The conservation status of European unionid species rests on the scientific knowledge of the 1980s, before the current revival of taxonomic reappraisals based on molecular characters. The taxonomic status of Unio mancus Lamarck, 1819, superficially similar to Unio pictorum (Linnaeus, 1758 and often synonymized with it, is re-evaluated based on a random sample of major French drainages and a systematic sample of historical type localities. We confirm the validity of U. mancus as a distinct species occurring in France and Spain, where it is structured into three geographical units here ranked as subspecies: U. m. mancus [Atlantic drainages, eastern Pyrenees, Spanish Mediterranean drainages], U. m. turtonii Payraudeau, 1826 [coastal drainages East of the Rhône and Corsica] and U. m. requienii Michaud, 1831 [Seine, Saône-Rhône, and coastal drainages West of the Rhône]. Many populations of Unio mancus have been extirpated during the 20th century and the remaining populations continue to be under pressure; U. mancus satisfies the criteria to be listed as «Endangered» in the IUCN Red List.
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Amon, Diva J; Ziegler, Amanda F; Kremenetskaia, Antonina; Mah, Christopher L; Mooi, Rich; O'Hara, Tim; Pawson, David L; Roux, Michel; Smith, Craig R
2017-01-01
There is growing interest in mining polymetallic nodules from the abyssal Clarion-Clipperton Zone (CCZ) in the tropical Pacific Ocean. Despite being the focus of environmental studies for decades, the benthic megafauna of the CCZ remain poorly known. In order to predict and manage the environmental impacts of mining in the CCZ, baseline knowledge of the megafauna is essential. The ABYSSLINE Project has conducted benthic biological baseline surveys in the UK Seabed Resources Ltd polymetallic-nodule exploration contract area (UK-1). Prior to these research cruises in 2013 and 2015, no biological studies had been done in this area of the eastern CCZ. Using a Remotely Operated Vehicle and Autonomous Underwater Vehicle, the megafauna within the UKSRL exploration contract area (UK-1) and at a site ~250 km east of the UK-1 area were surveyed, allowing us to make the first estimates of megafaunal morphospecies richness from the imagery collected. Here, we present an atlas of the abyssal echinoderm megafauna observed and collected during the ABYSSLINE cruises to the UK-1 polymetallic-nodule exploration contract area in the CCZ. There appear to be at least 62 distinct morphospecies (13 Asteroidea, 5 Crinoidea, 9 Echinoidea, 29 Holothuroidea and 6 Ophiuroidea) identified mostly by imagery but also using molecular barcoding for a limited number of animals that were collected. This atlas will aid the synthesis of megafaunal presence/absence data collected by contractors, scientists and other stakeholders undertaking work in the CCZ, ultimately helping to decipher the biogeography of the megafauna in this threatened habitat.
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Healy, J. M.
1996-06-01
Spermatozoa of the trigonioid bivalve Neotrigonia margaritacea (Lamarck) (Trigoniidae, Trigonioida) are examined ultrastructurally. A cluster of discoidal, proacrosomal vesicles (between 9 to 15 in number) constitutes the acrosomal complex at the nuclear apex. The nucleus is short (2.4 2.6 μm long, maximum diameter 2.2 μm), blunt-conical in shape, and exhibits irregular lacunae within its contents. Five or sometimes four round mitochondria are impressed into shallow depressions in the base of the nucleus as is a discrete centriolar fossa. The mitochondria surround two orthogonally arranged centrioles to form, collectively, the midpiece region. The distal centriole, anchored by nine satellite fibres to the plasma membrane, acts as a basal body to the sperm flagellum. The presence of numerous proacrosomal vesicles instead of a single, conical acrosomal vesicle sets Neotrigonia (and the Trigonioida) apart from other bivalves, with the exception of the Unionoida which are also known to exhibit this multivesicular condition. Spermatozoa of N. margaritacea are very similar to those of the related species Neotrigonia bednalli (Verco) with the exception that the proacrosomal vesicles of N. margaritacea are noticeably larger than those of N. bednalli.
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Hassan, Ruhana; Lee, Suet Yee; Morni, Wan Zabidii Wan
2017-01-01
Sea star (class Asteroidea, phylum Echinodermata) is one of the most successful marine organisms inhabiting a wide range of habitats. As one of the key stone species, sea stars are responsible for maintaining much of the local diversity of species within certain communities. Malaysian Exclusive Economic Zone (EEZ) Resource Survey had been carried out from 16th Aug to 6th Nov 2015 and one of the invertebrate by-catch organisms is sea star Stellaster childreni Gray, 1840. This study documents morphological characters and diet of the sea star, besides providing brief descriptions of the habitats based on particle size analysis and vessel log data sheet. A total of 217 individuals had been examined throughout this study. Fragments of flora and fauna were found in the gut including Mollusca (gastropod, bivalves, and scaphopods), sponge seagrass, and seaweed as well as benthic Foraminifera. Stellaster childreni were found at depth of 45 m to 185 m in the South China Sea off Sarawak Malaysia, with various sea bottom substrata. Approximately 41% of S. childreni were found at a mixture of sandy and muddy substratum, followed by mixture of sandy and coral (19.3%), muddy substratum (17.5%), coral substratum (11.5%), and sandy areas (10.6%). The widely distributed sea star on different types of sea beds suggested healthy deep sea ecosystem; thus Malaysia should explore further potential fisheries resources in the EEZ off Sarawak coast.
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Ruhana Hassan
2017-01-01
Full Text Available Sea star (class Asteroidea, phylum Echinodermata is one of the most successful marine organisms inhabiting a wide range of habitats. As one of the key stone species, sea stars are responsible for maintaining much of the local diversity of species within certain communities. Malaysian Exclusive Economic Zone (EEZ Resource Survey had been carried out from 16th Aug to 6th Nov 2015 and one of the invertebrate by-catch organisms is sea star Stellaster childreni Gray, 1840. This study documents morphological characters and diet of the sea star, besides providing brief descriptions of the habitats based on particle size analysis and vessel log data sheet. A total of 217 individuals had been examined throughout this study. Fragments of flora and fauna were found in the gut including Mollusca (gastropod, bivalves, and scaphopods, sponge seagrass, and seaweed as well as benthic Foraminifera. Stellaster childreni were found at depth of 45 m to 185 m in the South China Sea off Sarawak Malaysia, with various sea bottom substrata. Approximately 41% of S. childreni were found at a mixture of sandy and muddy substratum, followed by mixture of sandy and coral (19.3%, muddy substratum (17.5%, coral substratum (11.5%, and sandy areas (10.6%. The widely distributed sea star on different types of sea beds suggested healthy deep sea ecosystem; thus Malaysia should explore further potential fisheries resources in the EEZ off Sarawak coast.
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Francisco Brusa
2017-08-01
Full Text Available In this paper, we describe two new species of Syndesmis living in Pseudechinus magellanicus in the Southwest Atlantic Ocean. The new species have a long stylet in the male reproductive system, which is different from that of the known species of the genus. Specimens of Syndesmis selknami n. sp. have a ∼220-μm-long stylet (∼1/3 of the body length, 0.69 mm. This ratio is unique because only four species (Syndesmis echinorum, Syndesmis rubida, Syndesmis inconspicua and Syndesmis echiniacuti have similar stylet lengths but are larger in body sizes (3–5 mm. Specimens of Syndesmis aonikenki n. sp. have a ∼148-μm-long stylet (∼1/10 of the body length, 1.11 mm. Syndesmis pallida has a similar ratio but the uterus is located posteriorly, and the filament glands are very small and located in the posterior region of the body. These are the first flatworms reported parasitizing Pseudechinus magellanicus.
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Mottola, Nicolau [UNESP
2011-01-01
Analisou-se aqui o modo como o conceito de evolução, elaborado por Lamarck e Darwin, é apresentado nos livros didáticos de Biologia, selecionados pelo Programa Nacional do Livro Didático para o Ensino Médio (PNLEM), distribuídos em 2007 para todas as escolas da rede pública do Brasil. Para essa análise, foram consideradas as cinco teorias de Charles Robert Darwin (1809-1882), presente em sua obra A Origem das Espécies, a saber: a evolução propriamente dita, a ancestralidade comum, o gradualis...
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Christopher Concha
2011-07-01
Full Text Available El incremento de la frecuencia de malformaciones y la reducción de la viabilidad y fecundidad suelen ser las primeras manifestaciones de la depresión por consanguinidad en animales. El ostión del norte, Argopectenpurpuratus (Lamarck, 1819, es una especie hermnafrodita funcional con autofecundación parcial y durante la reproducción artificial puede presentar altos grados de autofecundación. En este trabajo se analizó la asociación de la tasa de autofecundación con la frecuencia de larvas malformadas y la supervivencia larval. Se desovaron adultos maduros y se recogieron separadamente los gametos femeninos del 5° pulso de liberación en adelante y los masculinos. Los ovocitos fueron fecundados con espermatozoides de otro individuo, formando familias de hermanos completos. La tasa de autofecundación se verificó por la proporción de ovocitos que entra en división en una muestra de ellos sin fecundar. La tasa de autofecundación varió entre familias de 0 a 100%, con distribución de frecuencias normal. La proporción de larvas malformadas se distribuyó al azar entre las familias analizadas, pero se correlacionó negativamente, en forma moderada pero significativa, con la tasa de autofecundación y la temperatura media del cultivo. Los datos sugieren que la autofecundación en las familias de ostiones puede favorecer una mayor homeostasis del desarrollo larval.Increased frequencies of malformations and the reduction of viability and fecundity are some of the first manifestations of inbreeding depression in animals. The northern scallop, Argopecten purpuratus (Lamarck, 1819, is a functional hermaphrodite species with partial self-fertilization. During artificial reproduction, this species may present high degrees of self-fertilization. In this work, the association between the selfing rate and the frequency of larval malformations and survival were analyzed. Mature adults were spawned, and female and male gametes were collected
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Nascimento, Luana B S; Leal-Costa, Marcos V; Coutinho, Marcela A S; Moreira, Nattacha dos S; Lage, Celso L S; Barbi, Nancy dos S; Costa, Sônia S; Tavares, Eliana S
2013-01-01
Antioxidant compounds protect plants against oxidative stress caused by environmental conditions. Different light qualities, such as UV-A radiation and blue light, have shown positive effects on the production of phenols in plants. Kalanchoe pinnata (Lamarck) Persoon (Crassulaceae) is used for treating wounds and inflammations. Some of these beneficial effects are attributed to the antioxidant activity of plant components. We investigated the effects of blue light and UV-A radiation supplementation on the total phenol content, antioxidant activity and chromatographic profile of aqueous extracts from leaves of K. pinnata. Monoclonal plants were grown under white light, white plus blue light and white plus UV-A radiation. Supplemental blue light improved the antioxidant activity and changed the phenolic profile of the extracts. Analysis by HPLC of supplemental blue-light plant extracts revealed a higher proportion of the major flavonoid quercetin 3-O-α-L-arabinopyranosyl (1→2) α-L-rhamnopyranoside, as well as the presence of a wide variety of other phenolic substances. These findings may explain the higher antioxidant activity observed for this extract. Blue light is proposed as a supplemental light source in the cultivation of K. pinnata, to improve its antioxidant activity. © 2012 Wiley Periodicals, Inc. Photochemistry and Photobiology © 2012 The American Society of Photobiology.
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Ellen Silva Lago
2006-12-01
Full Text Available A fruta jambolão (Syzygium cumini Lamarck é uma fruta de coloração roxa intensa e sabor agradável. Dado que não há na literatura nenhum relato de seu aproveitamento industrial, a produção de geléia de jambolão tornou-se uma interessante atividade de pesquisa. Este trabalho objetivou a elaboração e a avaliação das características físico-químicas e sensoriais da geléia obtida do jambolão. A fruta apresentou a seguinte composição química: cinzas, 0,34%; lipídeos, 0,30%; proteínas, 0,67%; carboidratos, 10,07%; fibras, 0,28%; umidade, 87,75%; frutose, 0,4%; glicose, 0,6%; antocianinas totais, 0,276%; substâncias pécticas, 0,245%; acidez titulável, 5,91%; sólidos solúveis, 9,00%; e pH, 3,9. A geléia obtida apresentou a seguinte composição: açúcares redutores, 20,99%; não-redutores, 18,01%; açúcares totais, 39,00%; pH, 3,42; sólidos solúveis, 67ºBrix; acidez titulável, 5,47%; e umidade, 29,63%. A análise sensorial foi realizada por uma equipe de 50 provadores não treinados que avaliaram os atributos cor, aparência, odor, textura, sabor e avaliação global, pelo método de escala hedônica com nove pontos. Os resultados obtidos mostraram que o atributo cor foi o que mais agradou aos provadores, o atributo odor foi o menos apreciado. Em conclusão, o estudo de análise sensorial revelou uma aceitação satisfatória da geléia de jambolão.Jambolan (Syzygium cumini Lamarck is a purple colored and very tasty fruit. Since there are no reports of its industrial use, the production of this jelly has become a matter of interest for research. The purpose of this work is to develop and evaluate the physical-chemical and sensory characteristics of the jelly made of jambolan. The fruit showed the following chemical composition: ash, 0.34%; lipids, 0.30%; proteins, 0.67%; carbohydrates, 10.07%; fibers, 0.28%; moisture, 87.75%; fructose, 0.4%; glucose, 0.6%; total anthocyanins, 0.276%; pectic substances, 0.245%; acidity
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Sylvia T. Oyarzún
1999-12-01
Full Text Available The reproductive cycle of the Chilean edible sea urchin, Loxechinus albus, was studied in two areas of the Magellan region, the Cockburn Channel (53°43´S, 70°42´W and Dawson Island (53°43´S, 72°00´W. Eleven monthly samplings were carried out from April 1996 to May 1997 in each area and samples of between 88 and 100 organisms were collected. Test diameter, total wet weight, and wet gonad weight was measured for each organism. Sex, gonad index, maturity index and gametogenic condition were estimated for each organism through histological analyses. The results indicate that L. albus in the Magellan region has an annual reproductive cycle in which the temporal sequence of different gametogenic processes can not be distinguished accurately due to the rapid and continuous gonadal recovery and gamete production after the spawning period. Although mature organisms were present most of the year, simultaneous spawning of males and females occurred from August to September in Dawson Island and from July to September in the Cockburn Channel. Gametes of those organisms that became mature after the spawning period were resorbed by nutritive phagocytes. Results from this study suggest that small-scale variability of spawning period in the Magellan region may be explained by the differences in food type and availability among areas. Our results also suggest that the Magellan region is an exception to the latitudinal pattern of spawning period reported for most of the Chilean coast. This large-scale variability may be explained by the simultaneous occurrence of low temperatures and short days during late winter and early spring.
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Abundance, size composition and benthic assemblages of two Mediterranean echinoids off the
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Elzahrae Elmasry
2015-12-01
Full Text Available This study is concerned with the variability in abundance, size composition and benthic assemblages of two echinoid species, the common sea urchin Paracentrotus lividus (Lamarck, 1816 and black urchin Arbacia lixula (Linnaeus, 1758 in the Southeastern Mediterranean (SEM along the coast of Alexandria, Egypt. Four seasonal trips were made during the years 2014–2015 covering 55 km of the shore with depths ranging between 3 and 9 m. The sea urchin species composition, density and size structure and distribution were compared. The associated macrobenthic invertebrates with prominent presence and biomass were observed as well as other benthic fauna and flora associations. The present results showed that P. lividus was the dominant echinoid spatially and temporally. A. lixula showed frequent occurrence in Sidi Bishr and Sidi Gaber stations in the spring season. The most dominant size class was the medium to large-sized classes for P. lividus and large-sized classes for A. lixula. The commercial size for the edible P. lividus represented 33% of the sampled population. Furthermore, the most dominant macrobenthic assemblages beside the echinoid population were primarily oysters, sea cucumbers, and mussels. Beside these, assemblage of seaweeds (red, green, brown and crustose algae, Porifera, Cnidaria, Crustacea, other Echinodermata, Bivalvia, Gastropoda, Tunicata, Bryozoa and Annelida were found. The present study shows that the investigated area represents stable habitats for the echinoid population with rich and diversified algal assemblages as well as other potential food resources.
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Investigations into propagation and characterisation of moringa (moringa oleifera lamarck)
International Nuclear Information System (INIS)
Owusu-Ansah, M.
2010-06-01
Moringa oleifera Lamarck is the predominant species of the thirteen-member monogenus Moringa of the family Moringaceae. Fourteen accessions collected from five regions were evaluated for agro-morphological characteristics. Agro-morphological characterisation revealed that the 14 accessions of Moringa exhibited variability with respect to 18 traits. Experiments were also conducted in the field and laboratory to assess the performance of stem cuttings, shoot tips, stumps of decapitated plantlets and epicotyls under nursery and in vitro conditions. Stem cuttings bearing only three nodes were raised in three different types of soil while in vitro cultures were initiated on Murashige and Skoog (MS) basal medium, supplemented with varying concentrations of 6-Benzyl aminopurine (BAP). Three-node stem cuttings sprouted well in the nursery (up to 70%) with loamy soil emerging as the best medium but the survival of sprouts was low, due to poor root development. In vitro regeneration of plantlets using shoot tips was enhanced by addition of 1.5mg/L of BAP in the culture medium and greater success was achieved with 24-month old donor plants compared to 6-month old donor plants even though the former developed callus. Regeneration was also achieved from stumps of decapitated plantlets as well as epicotyl segments without addition of BAP as this suppressed both survival and root development. In addition, twelve out of the fourteen accessions were assessed with respect to variation in mineral composition, oil content (OC), total phenolics composition (TPC) and antioxidant activity (AOA) of dried leaf samples. Determination of mineral was achieved through the use of fast sequential atomic absorption spectrometer, oil content by the nuclear magnetic resonance equipment and total phenolics content was estimated spectrophotometrically at 760nm based on Folin-Ciocalteau's (FC) method with some modification, using Gallic acid as reference standard. Antioxidant activity was also
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Weerdt, de Wallie H.
1981-01-01
The historical background of the taxonomic problems in the fire-coral, Millepora, is reviewed. The growth forms of the Caribbean species: Millepora alcicornis Linnaeus, M. complanata Lamarck and M. squarrosa Lamarck are investigated in relation with environmental factors: water movement, current,
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Caio Cesar-Ribeiro
2010-06-01
Full Text Available In this work, the chronic toxicity of a mixture of light-stick chemicals and water was tested. The light-stick is used in fishery activities to catch swordfish. The tubes were collected on the beaches of the Costa dos Coqueiros - BA, Brazil, in the period from 14th to 31st July 2007. The method used was a short chronic toxicity test where embryos of the sea urchins Echinometra lucunter and Lytechinus variegatus were exposed to a stock solution consisting of the supernatant formed from a mixture of sea water and the orange-colored light-stick chemical. After a preliminary test, concentrations defined were 0.002, 0.003, 0.01, 0.02, 0.1, 1.0% of stock solution. The final test ran for 36 hours for E. Lucunter and 24 hours for L. variegatus with 4 replicates for each concentration. The value of EC50 - 36h was 0.062% with confidence limits ranging from 0.042 to 0.079% and the EC50 - 24h was 0.011% with confidence limits ranging from 0.009 to 0.014%, i.e., the chemical mix present in the light-stick is potentially toxic. So, as these flags are commonly used for fishing there is potential danger in their disposal in the open ocean.O objetivo deste trabalho foi avaliar a toxicidade crônica da água do mar em contato com o líquido contido no light-stick, sinalizador utilizado em pesca de espinhel de superfície para a captura de espadarte. Os tubos foram coletados nas praias da Costa dos Coqueiros - BA, no período de 14 a 31 de Julho de 2007. O método utilizado para a verificação da toxicidade crônica foi o teste de curta duração com embriões de ouriço-do-mar Echinometra lucunter e Lytechinus variegatus, os ensaios foram realizados com solução estoque que consiste do sobrenadante formado a partir de uma mistura de água do mar com o líquido do sinalizador de coloração laranja. Após um teste preliminar as concentrações definidas foram 0.002; 0.003; 0.01; 0.02; 0.1; 1.0%. O teste definitivo teve duração de 36 horas para E. lucunter e 24 horas para L. variegatus, sendo preparadas 4 réplicas para cada concentração. O valor da CE50 - 36h encontrado foi de 0.062% com limites de aceitabilidade variando de 0.042 a 0.079% e a CE50 - 24h encontrada foi de 0.011% com limites de aceitabilidade variando de 0.009 a 0.014%, ou seja, os compostos químicos presentes no light-stick são potencialmente tóxicos. Portanto já que esses sinalizadores são utilizados comumente como petrechos de pesca há a necessidade de que eles sejam recolhidos, pois podem causar efeitos adversos quando abrem nos oceanos.
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Temporal and Spatial Distribution Patterns of Echinoderm Larvae in La Parguera, Puerto Rico
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Stacey M Williams
2010-10-01
Full Text Available This study describes temporal and spatial abundance patterns of echinoderm larvae in La Parguera, Puerto Rico. For the temporal study, larvae were sampled by a series of monthly tows taken with a 64μm mesh net between the new and full moon from April 2005 to July 2006, September 2006 and August 2007. In order to measure spatial variation of echinoderm larval bundances, oblique tows were taken with 64 and 202μm mesh nets at seven different sites within the shelf, at the shelf-edge, and at a nearby oceanic stations during August 2007. Overall, Echinoidea (sea urchin exhibited the highest abundance with a total of 11 921 larvae, representing 52.5% of the total collection. Ophiuroidea (brittle star ranked second in abundance with 45.6% of the total larvae. Holothuroidea (sea cucumber and Asteroidea larvae (sea star accounted for less than 2% of the total echinoderm larval collection. Early larval stages (2-8 day old of Diadema antillarum represented 20% of the total Echinoidea larvae. There was no marked seasonal trend of echinoderm larval abundance; Echinoidea and Ophiuroidea larvae were present in all monthly samples indicating that reproduction occurs year-round. Peak abundances of later-stage Echinoidea larvae were observed during January, July and October and of later-stage Ophiuroidea larvae during June, August and October. The observed peaks of later-stage larval abundances may be indicative of higher recruitment activity during these months. There was a significant difference of echinoderm larval abundance between spatial stations, with higher abundances collected at the shelf-edge. Later-stage (~24 day old D. antillarum larvae were mostly collected at shelf-edge and oceanic locations. In addition, the 64mm mesh net was more efficient for collection of echinoderm larvae than the 202mm mesh net. Rev. Biol. Trop. 58 (Suppl. 3: 81-88. Epub 2010 October 01.
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African Journals Online (AJOL)
TOSHIBA
2015-06-23
Jun 23, 2015 ... the FMRFamide-related peptides family, in echinoderm species ... water balance, neuroendocrine and neuromodulatory activities ..... London) for his contributions to this work and help with antibody ... Kwalalumpur, Malaysia.
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African Journals Online (AJOL)
TOSHIBA
2015-06-23
Jun 23, 2015 ... 4Aquatic Animal Biotechnology Research Center, Surat Thani Campus, Surat Thani 84100, Thailand. Received ... medicinal value but there is a threat of extinction on the ..... observed to cause relaxation of intestinal muscles.
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Iain C Wilkie
Full Text Available The compass depressors (CDs of the sea-urchin lantern are ligaments consisting mainly of discontinuous collagen fibrils associated with a small population of myocytes. They are mutable collagenous structures, which can change their mechanical properties rapidly and reversibly under nervous control. The aims of this investigation were to characterise the baseline (i.e. unmanipulated static mechanical properties of the CDs of Paracentrotus lividus by means of creep tests and incremental force-extension tests, and to determine the effects on their mechanical behaviour of a range of agents. Under constant load the CDs exhibited a three-phase creep curve, the mean coefficient of viscosity being 561±365 MPa.s. The stress-strain curve showed toe, linear and yield regions; the mean strain at the toe-linear inflection was 0.86±0.61; the mean Young's modulus was 18.62±10.30 MPa; and the mean tensile strength was 8.14±5.73 MPa. Hyaluronidase from Streptomyces hyalurolyticus had no effect on creep behaviour, whilst chondroitinase ABC prolonged primary creep but had no effect on secondary creep or on any force-extension parameters; it thus appears that neither hyaluronic acid nor sulphated glycosaminoglycans have an interfibrillar load transfer function in the CD. Acetylcholine, the muscarinic agonists arecoline and methacholine, and the nicotinic agonists nicotine and 1-[1-(3,4-dimethyl-phenyl-ethyl]-piperazine produced an abrupt increase in CD viscosity; the CDs were not differentially sensitive to muscarinic or nicotinic agonists. CDs showed either no, or no consistent, response to adrenaline, L-glutamic acid, 5-hydroxytryptamine and γ-aminobutyric acid. Synthetic echinoid tensilin-like protein had a weak and inconsistent stiffening effect, indicating that, in contrast to holothurian tensilins, the echinoid molecule may not be involved in the regulation of collagenous tissue tensility. We compare in detail the mechanical behaviour of the CD with that of mammalian tendon and highlight its potential as a model system for investigating poorly understood aspects of the ontogeny and phylogeny of vertebrate collagenous tissues.
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Veiga, Puri; Rubal, Marcos; Cacabelos, Eva; Moreira, Juan; Sousa-Pinto, Isabel
2013-10-01
The crustose calcareous red macroalgae Lithophyllum byssoides (Lamarck) Foslie is a common ecosystem engineer along the Atlantic and Mediterranean coast of the Iberian Peninsula. This species is threatened by several anthropogenic impacts acting at different spatial scales, such as pollution or global warming. The aim of this study is to identify scales of spatial variation in the abundance and fragmentation patterns of L. byssoides along the Atlantic coast of the Iberian Peninsula. For this aim we used a hierarchical sampling design considering four spatial scales (from metres to 100s of kilometres). Results of the present study indicated no significant variability among regions investigated whereas significant variability was found at the scales of shore and site in spatial patterns of abundance and fragmentation of L. byssoides. Variance components were higher at the spatial scale of shore for abundance and fragmentation of L. byssoides with the only exception of percentage cover and thus, processes acting at the scale of 10s of kilometres seem to be more relevant in shaping the spatial variability both in abundance and fragmentation of L. byssoides. These results provided quantitative estimates of abundance and fragmentation of L. byssoides at the Atlantic coast of the Iberian Peninsula establishing the observational basis for future assessment, monitoring and experimental investigations to identify the processes and anthropogenic impacts affecting L. byssoides populations. Finally we have also identified percentage cover and patch density as the best variables for long-term monitoring programs aimed to detect future anthropogenic impacts on L. byssoides. Therefore, our results have important implications for conservation and management of this valuable ecosystem engineer along the Atlantic coast of the Iberian Peninsula.
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Nakao, Minoru; Lavikainen, Antti; Iwaki, Takashi; Haukisalmi, Voitto; Konyaev, Sergey; Oku, Yuzaburo; Okamoto, Munehiro; Ito, Akira
2013-05-01
The cestode family Taeniidae generally consists of two valid genera, Taenia and Echinococcus. The genus Echinococcus is monophyletic due to a remarkable similarity in morphology, features of development and genetic makeup. By contrast, Taenia is a highly diverse group formerly made up of different genera. Recent molecular phylogenetic analyses strongly suggest the paraphyly of Taenia. To clarify the genetic relationships among the representative members of Taenia, molecular phylogenies were constructed using nuclear and mitochondrial genes. The nuclear phylogenetic trees of 18S ribosomal DNA and concatenated exon regions of protein-coding genes (phosphoenolpyruvate carboxykinase and DNA polymerase delta) demonstrated that both Taenia mustelae and a clade formed by Taenia parva, Taenia krepkogorski and Taenia taeniaeformis are only distantly related to the other members of Taenia. Similar topologies were recovered in mitochondrial genomic analyses using 12 complete protein-coding genes. A sister relationship between T. mustelae and Echinococcus spp. was supported, especially in protein-coding gene trees inferred from both nuclear and mitochondrial data sets. Based on these results, we propose the resurrection of Hydatigera Lamarck, 1816 for T. parva, T. krepkogorski and T. taeniaeformis and the creation of a new genus, Versteria, for T. mustelae. Due to obvious morphological and ecological similarities, Taenia brachyacantha is also included in Versteria gen. nov., although molecular evidence is not available. Taenia taeniaeformis has been historically regarded as a single species but the present data clearly demonstrate that it consists of two cryptic species. Copyright © 2013 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.
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Directory of Open Access Journals (Sweden)
S. Andersen
2013-10-01
Full Text Available As a result of high anthropogenic CO2 emissions, the concentration of CO2 in the oceans has increased, causing a decrease in pH, known as ocean acidification (OA. Numerous studies have shown negative effects on marine invertebrates, and also that the early life stages are the most sensitive to OA. We studied the effects of OA on embryos and unfed larvae of the great scallop (Pecten maximus Lamarck, at pCO2 levels of 469 (ambient, 807, 1164, and 1599 μatm until seven days after fertilization. To our knowledge, this is the first study on OA effects on larvae of this species. A drop in pCO2 level the first 12 h was observed in the elevated pCO2 groups due to a discontinuation in water flow to avoid escape of embryos. When the flow was restarted, pCO2 level stabilized and was significantly different between all groups. OA affected both survival and shell growth negatively after seven days. Survival was reduced from 45% in the ambient group to 12% in the highest pCO2 group. Shell length and height were reduced by 8 and 15%, respectively, when pCO2 increased from ambient to 1599 μatm. Development of normal hinges was negatively affected by elevated pCO2 levels in both trochophore larvae after two days and veliger larvae after seven days. After seven days, deformities in the shell hinge were more connected to elevated pCO2 levels than deformities in the shell edge. Embryos stained with calcein showed fluorescence in the newly formed shell area, indicating calcification of the shell at the early trochophore stage between one and two days after fertilization. Our results show that P. maximus embryos and early larvae may be negatively affected by elevated pCO2 levels within the range of what is projected towards year 2250, although the initial drop in pCO2 level may have overestimated the effect of the highest pCO2 levels. Future work should focus on long-term effects on this species from hatching, throughout the larval stages, and further into the
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Impact of benthic disturbance on megafauna in Central Indian Basin
Digital Repository Service at National Institute of Oceanography (India)
Rodrigues, N; Sharma, R.; Nath, B.N
, M., 1980. La nutrition d’echinodermes abyssaux I. Alimentation des holothuries. Marine Biology 60, 17–26. Koelher, R., Vaney, C., 1905. Echinodermata of the Indian Museum, Holothuroidea. Indian Museum, Calcutta. Lampitt, R.S., Rice, A.L., Thurston, M.... Pawson, D.L., Foell, E.J., 1983. Atlas of photographs of megafauna from the study area. Report No. MS – 200 – 146, 120pp. Pawson, D.L., Foell, E.J., 1986. Peniagone leander new species, an abyssal benthopelagic sea cucumber (Echinodermata: Holothuroidea...
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Weerdt, de, Wallie H.
1981-01-01
The historical background of the taxonomic problems in the fire-coral, Millepora, is reviewed. The growth forms of the Caribbean species: Millepora alcicornis Linnaeus, M. complanata Lamarck and M. squarrosa Lamarck are investigated in relation with environmental factors: water movement, current, light and turbidity. Several sites on Curaçao and Bonaire were visited and all forms of Millepora collected. The localities have been divided in biotopes and the relative frequencies of the growth fo...
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Sensorial, physical and chemical evaluation of bio-fortified Ipomoea batatas
Mara N.G. Santos; Joice V.C. Orsine; Alexandre I. de A. Pereira; Roberto Cañete; María R.C.G. Novaes
2014-01-01
Context: Bio-fortified sweet potato, Ipomoea batatas (L.) Lamarck beta-carotene rich, has been included in the most vulnerable population’s diet with the purpose of reducing health disturbances associated with hipovitaminosis. Aims:To evaluate a physical and chemical analysis of total carotenes and beta-carotene and to determine the antioxidant potential as well as to carry out a sensorial analysis of the bio-fortified Ipomoea batatas (L.) Lamarck (BDB) in nature and processed. Method...
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Fukushima, Caroline Sayuri; Bertani, Rogério
2017-01-01
The genus Avicularia Lamarck, 1818 is revised and all species are rediagnosed. The type species, described as Aranea avicularia Linnaeus, 1758, is the oldest mygalomorph species described and its taxonomic history is extensive and confusing. Cladistic analyses using both equal and implied weights were carried out with a matrix of 46 taxa from seven theraphosid subfamilies, and 71 morphological and ecological characters. The optimal cladogram found with Piwe and concavity = 6 suggests Avicularia and Aviculariinae are monophyletic. Subfamily Aviculariinae includes Avicularia Lamarck, 1818, Typhochlaena C. L. Koch, 1850, Tapinauchenius Ausserer, 1871, Stromatopelma Karsch, 1881, Ephebopus Simon, 1892, Psalmopoeus Pocock, 1895, Heteroscodra Pocock, 1899, Iridopelma Pocock, 1901, Pachistopelma Pocock, 1901, Ybyrapora gen. n. , Caribena gen. n. , and Antillena gen. n. The clade is supported by well-developed scopulae on tarsi and metatarsi, greatly extended laterally. Avicularia synapomorphies are juveniles bearing black tarsi contrasting with other lighter articles; spermathecae with an accentuated outwards curvature medially, and male palpal bulb with embolus medial portion and tegulum's margin form an acute angle in retrolateral view. Avicularia is composed of twelve species, including three new species: Avicularia avicularia (Linnaeus, 1818), Avicularia glauca Simon, 1891, Avicularia variegata (F. O. Pickard-Cambridge, 1896) stat. n., Avicularia minatrix Pocock, 1903, Avicularia taunayi (Mello-Leitão, 1920), Avicularia juruensis Mello-Leitão, 1923, Avicularia rufa Schiapelli & Gerschman, 1945, Avicularia purpurea Kirk, 1990, Avicularia hirschii Bullmer et al. 2006, Avicularia merianae sp. n. , Avicularia lynnae sp. n. , and Avicularia caei sp. n. . Avicularia species are distributed throughout Mexico, Costa Rica, Panama, Trinidad and Tobago, Venezuela, Guyana, Suriname, French Guiana, Colombia, Ecuador, Peru, Bolivia, and Brazil. Three new genera are erected to
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Directory of Open Access Journals (Sweden)
Caroline Sayuri Fukushima
2017-03-01
Full Text Available The genus Avicularia Lamarck, 1818 is revised and all species are rediagnosed. The type species, described as Aranea avicularia Linnaeus, 1758, is the oldest mygalomorph species described and its taxonomic history is extensive and confusing. Cladistic analyses using both equal and implied weights were carried out with a matrix of 46 taxa from seven theraphosid subfamilies, and 71 morphological and ecological characters. The optimal cladogram found with Piwe and concavity = 6 suggests Avicularia and Aviculariinae are monophyletic. Subfamily Aviculariinae includes Avicularia Lamarck, 1818, Typhochlaena C. L. Koch, 1850, Tapinauchenius Ausserer, 1871, Stromatopelma Karsch, 1881, Ephebopus Simon, 1892, Psalmopoeus Pocock, 1895, Heteroscodra Pocock, 1899, Iridopelma Pocock, 1901, Pachistopelma Pocock, 1901, Ybyrapora gen. n., Caribena gen. n., and Antillena gen. n. The clade is supported by well-developed scopulae on tarsi and metatarsi, greatly extended laterally. Avicularia synapomorphies are juveniles bearing black tarsi contrasting with other lighter articles; spermathecae with an accentuated outwards curvature medially, and male palpal bulb with embolus medial portion and tegulum’s margin form an acute angle in retrolateral view. Avicularia is composed of twelve species, including three new species: Avicularia avicularia (Linnaeus, 1818, Avicularia glauca Simon, 1891, Avicularia variegata (F. O. Pickard-Cambridge, 1896 stat. n., A. minatrix Pocock, 1903, Avicularia taunayi (Mello-Leitão, 1920, Avicularia juruensis Mello-Leitão, 1923, Avicularia rufa Schiapelli & Gerschman, 1945, Avicularia purpurea Kirk, 1990, A. hirschii Bullmer et al. 2006, Avicularia merianae sp. n., A. lynnae sp. n., and A. caei sp. n.. Avicularia species are distributed throughout Mexico, Costa Rica, Panama, Trinidad and Tobago, Venezuela, Guyana, Suriname, French Guiana, Colombia, Ecuador, Peru, Bolivia, and Brazil. Three new genera are erected to accommodate former
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Echinodermata: Holothuroidea: Dendrochirotida
African Journals Online (AJOL)
10-25 mm. Whitish. Present. Arranged in double rows along the radii, diminishing to single rows towards the anterior and posterior ends, also found scattered along interambulacra, becoming denser ventrally. Radial plates subdivided. interracial plates compact. non-bitld anteriorly. Rounded, compact, multi-layered plates,.
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Indian Academy of Sciences (India)
Eastern Coast of Arabia and at Bagh on the Narbada in the collection of the Geological Society,' O.J.G.S., 1865, 21, 349-63. 'Notes on Echinoidea of the Cretaceous Series of the Lower. Narbada valley with remarks upon their Geological age,' Rec. G.S.I., 1887, 20, 81-92. 11. Fourteau, R. ... “Les Échinides des Bagh Beds,' ...
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Historical aspects of meetings, publication series, and digital resources dedicated to echinoderms
Directory of Open Access Journals (Sweden)
Alexander Ziegler
2014-03-01
Full Text Available Half a century after the first scientific meeting dedicated to marine spiny-skinned animals (Deuterostomia: Echinodermata was held in Washington, DC, we take this opportunity to provide information on a number of historical aspects related to the echinoderm scientific community. Apart from shedding light on the historical origins of modern echinoderm conferences, the present contribution presents photographs taken during the first meeting of echinoderm researchers in 1963 as well as during the first installments of the International Echinoderm Conference and the European Conference on Echinoderms. Furthermore, we provide background information on publication series dedicated solely to the Echinodermata as well as descriptions of selected digital resources that focus on echinoderms. Finally, we present a number of echinoderm conference logos and flyers in addition to selected information about specific echinoderm meetings.
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Directory of Open Access Journals (Sweden)
Michael J. Wynne
2008-06-01
Full Text Available The type specimen of the red alga Alysium holtingii C. Agardh, described from Brazil, is located in the Lund Herbarium, and it is depicted for the first time in a publication. It is taxonomically identical to Dichotomaria obtusata (J. Ellis and Solander Lamarck and thus can be treated as a later taxonomic synonym. Alysium is regarded as congeneric with Dichotomaria.O espécime tipo da alga vermelha Alysium holtingii C. Agardh, descrito para o Brasil, está localizado no Herbário Lund, e é aqui apresentado. Ele é taxonomicamente idêntico a Dichotomaria obtusata (J. Ellis e Solander Lamarck e portanto deve ser tratado como um sinônimo taxonômico posterior. Alysium é considerado como congenérico com Dichotomaria.
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Benthos off Cochin, Southwest coast of India
Digital Repository Service at National Institute of Oceanography (India)
Harkantra, S.N.; Parulekar, A.H.
Macro-invertebrate benthic fauna off Cochin mainly composed of polychaeta (82.45%), crustacea (7.62%), mollusca (5.92%), sipuncula (2.25%), nemertinea (0.96%) and echinodermata (0.80%). The maximum population density and biomass values were 304 plus...
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Biological activities and biomedical potential of sea cucumber (Stichopus japonicus: a review
Directory of Open Access Journals (Sweden)
Gun-Woo Oh
2017-11-01
Full Text Available Abstract Members of the phylum Echinodermata, commonly known as echinoderms, are exclusively marine invertebrates. Among the Echinodermata, sea cucumber belongs to the family Holothuroidea. The sea cucumber Stichopus (Apostichous japonicus (Selenka is an invertebrate animal inhabiting the coastal sea around Korean, Japan, China, and Russia. Sea cucumber has a significant commercial value, because it contains valuable nutrients such as vitamins and minerals. They possess a number of distinctive biologically and pharmacologically important compounds. In particular, the body wall of sea cucumber is a major edible part. It consists of peptide, collagen, gelatin, polysaccharide, and saponin, which possess several biological activities such as anti-cancer, anti-coagulation, anti-oxidation, and anti-osteoclastogenesis. Furthermore, the regenerative capacity of sea cucumber makes it a medically important organism. This review presents the various biological activities and biomedical potential of sea cucumber S. japonicus.
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(Lamarck, 1798) (Cephalopoda, Ommastrephidae)
African Journals Online (AJOL)
spamer
Females dominated the samples (78%) and attained larger size and ... Mature females were found mainly during winter and mature males nearly year-round, indicating that they .... importance, both accounting for <1%. A striking observation ...
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Exploring the Sea Urchin Neuropeptide Landscape by Mass Spectrometry.
Monroe, Eric B; Annangudi, Suresh P; Wadhams, Andinet A; Richmond, Timothy A; Yang, Ning; Southey, Bruce R; Romanova, Elena V; Schoofs, Liliane; Baggerman, Geert; Sweedler, Jonathan V
2018-05-01
Neuropeptides are essential cell-to-cell signaling messengers and serve important regulatory roles in animals. Although remarkable progress has been made in peptide identification across the Metazoa, for some phyla such as Echinodermata, limited neuropeptides are known and even fewer have been verified on the protein level. We employed peptidomic approaches using bioinformatics and mass spectrometry (MS) to experimentally confirm 23 prohormones and to characterize a new prohormone in nervous system tissue from Strongylocentrotus purpuratus, the purple sea urchin. Ninety-three distinct peptides from known and novel prohormones were detected with MS from extracts of the radial nerves, many of which are reported or experimentally confirmed here for the first time, representing a large-scale study of neuropeptides from the phylum Echinodermata. Many of the identified peptides and their precursor proteins have low homology to known prohormones from other species/phyla and are unique to the sea urchin. By pairing bioinformatics with MS, the capacity to characterize novel peptides and annotate prohormone genes is enhanced. Graphical Abstract.
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A brief review of the immunobiology of eledone cirrhosa | Malham ...
African Journals Online (AJOL)
Lamarck) and the haemocytes cultured for up to 72 h. Sampling results in an increase in the number of circulating haemocytes per mland in the percentage of haemocytes containing cytoplasmic granules, and a change in the staining pattern of the ...
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Weismann, Wittgenstein and the homunculus fallacy.
Smit, Harry
2010-09-01
A problem that has troubled both neo-Darwinists and neo-Lamarckians is whether instincts involve knowledge. This paper discusses the contributions to this problem of the evolutionary biologist August Weismann and the philosopher Ludwig Wittgenstein. Weismann discussed an empirical homunculus fallacy: Lamarck's theory mistakenly presupposes a homunculus in the germ cells. Wittgenstein discussed a conceptual homunculus fallacy which applies to Lamarck's theory: it is mistaken to suppose that knowledge is stored in the brain or DNA. The upshot of these two fallacies is that instincts arise through a neo-Darwinian process but are not cognitions in the sense that they involve (the recollection of stored) knowledge. Although neo-Lamarckians have rightly argued that learning processes may contribute to the development of instincts, their ideas about the role of knowledge in the evolution and development of instincts are mistaken. Copyright © 2010 Elsevier Ltd. All rights reserved.
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Lower Oligocene bivalves of Ramanian Stage from Kachchh ...
Indian Academy of Sciences (India)
Sehe area of western Kachchh considered their. Bed Nos. 4 and 5 as .... with very thin population. The Bermoti stream ...... Recent; Indo–Pacific. Subgenus: .... Type species: Cardium discors Lamarck' 1805; T. Eocene–Miocene; Europe–Asia ..... Shuto Tsugio 1971 Neogene Bivalves from Panay Island, the. Philippines.
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Tropical Freshwater Biology - Vol 18, No 2 (2009)
African Journals Online (AJOL)
Organic fertilizer decomposition and nutrient loads in water reservoir with changing temperature, Wakiso – Ug · EMAIL FULL TEXT EMAIL FULL TEXT ... benthos in response to the biodeposition and bioturbation activities of the freshwater mussel Lamellidens marginalis (Lamarck) · EMAIL FULL TEXT EMAIL FULL TEXT
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from Pyura stolollifera (Echinodermata, Ascidiacea)
African Journals Online (AJOL)
1994-05-05
May 5, 1994 ... Doropygus pyurus verskil van die meeste van die spesies in die genus t.o.v. die struktuur van die antennule an monddele, maar veral van D. pulex a.g.v. die unieke samestelling van die swempote. Species of the genus DoropyguJ Thorell, 1859 are cosmopo- litan, pharyngeal associates of ascidians, which ...
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African Journals Online (AJOL)
Susithra, N. Vol 18, No 2 (2009) - Articles A mesocosm analytical study on the ecological interactions of certain benthos in response to the biodeposition and bioturbation activities of the freshwater mussel Lamellidens marginalis (Lamarck) Abstract. ISSN: 0795-0101. AJOL African Journals Online. HOW TO USE AJOL.
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Mathison, Jane
1976-01-01
The idea of evolution is examined in a historical perspective in this article. Considerable discussion is given to the works of Lamarck and Darwin. The evolutionary process is also examined with respect to philosophy, art and music history, and man's place in nature. References are included. (MA)
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Towards an alternative evolution model.
van Waesberghe, H
1982-01-01
Lamarck and Darwin agreed on the inconstancy of species and on the exclusive gradualism of evolution (nature does not jump). Darwinism, revived as neo-Darwinism, was almost generally accepted from about 1930 till 1960. In the sixties the evolutionary importance of selection has been called in question by the neutralists. The traditional conception of the gene is disarranged by recent molecular-biological findings. Owing to the increasing confusion about the concept of genotype, this concept is reconsidered. The idea of the genotype as a cluster of genes is replaced by a cybernetical interpretation of the genotype. As nature does jump, exclusive gradualism is dismissed. Saltatory evolution is a natural phenomenon, provided by a sudden collapse of the thresholds which resist against evolution. The fossil record and the taxonomic system call for a macromutational interpretation. As Lamarck and Darwin overlooked the resistance of evolutionary thresholds, an alternative evolution model is needed, the first to be constructed on a palaeontological and taxonomic basis.
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Ecology of benthic production in the coastal zone of Goa
Digital Repository Service at National Institute of Oceanography (India)
Harkantra, S.N.; Parulekar, A.H.
was comprised of Polychaeta (58.5%), Mollusca (18.1%), Crustacea (9.1%), Echinodermata (7.1%) and other minor taxa (7.3%) Population count and biomass varied from 25 to 7823 m-2 (X- = 1256 m-2) and 0.2 to 2251.25 g m-2 (X- = 67.07 g m-2) respectively The higher...
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Directory of Open Access Journals (Sweden)
Joaquim Olinto Branco
2002-03-01
Full Text Available From January to December 1995, 332 individuals of the Callinectes ornatus species were collected from the Itapocoroy inlet in Penha, Sta. Catarina, Brazil to study its natural diet and the seasonal variations of diet. Results showed a diversified trophic spectrum with a generalized dietary strategy comprising the algae, macrophyta, foraminiferida, mollusca, polychaeta, crustacea, echinodermata, Osteichthyes and NIOM (Nonidentified Organic Matter groups.Alimentação natural de Callinectes ornatus Ordway, 1863 (Decapoda, Portunidae na Armação do Itapocoroy, Penha, SC - Brasil. No período de janeiro a dezembro de 1995, foram coletados 332 indivíduos de Callinectes ornatus, procedentes da Armação do Itapocoroy (Penha, SC. Foi estudada a alimentação natural da espécie e as variações sazonais da dieta. Os resultados mostram um espectro trófico diversificado, com estratégia alimentar generalista, sendo Algas, Macrófitas, Foraminiferida, Mollusca, Polychaeta, Crustacea, Echinodermata, Osteichthyes e matéria orgânica não identificada, os grupos que compõem sua dieta.
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Exploring the Sea Urchin Neuropeptide Landscape by Mass Spectrometry
Monroe, Eric B.; Annangudi, Suresh P.; Wadhams, Andinet A.; Richmond, Timothy A.; Yang, Ning; Southey, Bruce R.; Romanova, Elena V.; Schoofs, Liliane; Baggerman, Geert; Sweedler, Jonathan V.
2018-04-01
Neuropeptides are essential cell-to-cell signaling messengers and serve important regulatory roles in animals. Although remarkable progress has been made in peptide identification across the Metazoa, for some phyla such as Echinodermata, limited neuropeptides are known and even fewer have been verified on the protein level. We employed peptidomic approaches using bioinformatics and mass spectrometry (MS) to experimentally confirm 23 prohormones and to characterize a new prohormone in nervous system tissue from Strongylocentrotus purpuratus, the purple sea urchin. Ninety-three distinct peptides from known and novel prohormones were detected with MS from extracts of the radial nerves, many of which are reported or experimentally confirmed here for the first time, representing a large-scale study of neuropeptides from the phylum Echinodermata. Many of the identified peptides and their precursor proteins have low homology to known prohormones from other species/phyla and are unique to the sea urchin. By pairing bioinformatics with MS, the capacity to characterize novel peptides and annotate prohormone genes is enhanced. [Figure not available: see fulltext.
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Exploring the Sea Urchin Neuropeptide Landscape by Mass Spectrometry
Monroe, Eric B.; Annangudi, Suresh P.; Wadhams, Andinet A.; Richmond, Timothy A.; Yang, Ning; Southey, Bruce R.; Romanova, Elena V.; Schoofs, Liliane; Baggerman, Geert; Sweedler, Jonathan V.
2018-05-01
Neuropeptides are essential cell-to-cell signaling messengers and serve important regulatory roles in animals. Although remarkable progress has been made in peptide identification across the Metazoa, for some phyla such as Echinodermata, limited neuropeptides are known and even fewer have been verified on the protein level. We employed peptidomic approaches using bioinformatics and mass spectrometry (MS) to experimentally confirm 23 prohormones and to characterize a new prohormone in nervous system tissue from Strongylocentrotus purpuratus, the purple sea urchin. Ninety-three distinct peptides from known and novel prohormones were detected with MS from extracts of the radial nerves, many of which are reported or experimentally confirmed here for the first time, representing a large-scale study of neuropeptides from the phylum Echinodermata. Many of the identified peptides and their precursor proteins have low homology to known prohormones from other species/phyla and are unique to the sea urchin. By pairing bioinformatics with MS, the capacity to characterize novel peptides and annotate prohormone genes is enhanced. [Figure not available: see fulltext.
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Temporal and Spatial Distribution Patterns of Echinoderm Larvae in La Parguera, Puerto Rico
Directory of Open Access Journals (Sweden)
Stacey M Williams
2010-10-01
Full Text Available This study describes temporal and spatial abundance patterns of echinoderm larvae in La Parguera, Puerto Rico. For the temporal study, larvae were sampled by a series of monthly tows taken with a 64μm mesh net between the new and full moon from April 2005 to July 2006, September 2006 and August 2007. In order to measure spatial variation of echinoderm larval bundances, oblique tows were taken with 64 and 202μm mesh nets at seven different sites within the shelf, at the shelf-edge, and at a nearby oceanic stations during August 2007. Overall, Echinoidea (sea urchin exhibited the highest abundance with a total of 11 921 larvae, representing 52.5% of the total collection. Ophiuroidea (brittle star ranked second in abundance with 45.6% of the total larvae. Holothuroidea (sea cucumber and Asteroidea larvae (sea star accounted for less than 2% of the total echinoderm larval collection. Early larval stages (2-8 day old of Diadema antillarum represented 20% of the total Echinoidea larvae. There was no marked seasonal trend of echinoderm larval abundance; Echinoidea and Ophiuroidea larvae were present in all monthly samples indicating that reproduction occurs year-round. Peak abundances of later-stage Echinoidea larvae were observed during January, July and October and of later-stage Ophiuroidea larvae during June, August and October. The observed peaks of later-stage larval abundances may be indicative of higher recruitment activity during these months. There was a significant difference of echinoderm larval abundance between spatial stations, with higher abundances collected at the shelf-edge. Later-stage (~24 day old D. antillarum larvae were mostly collected at shelf-edge and oceanic locations. In addition, the 64mm mesh net was more efficient for collection of echinoderm larvae than the 202mm mesh net. Rev. Biol. Trop. 58 (Suppl. 3: 81-88. Epub 2010 October 01.Este estudio describe patrones de abundancia temporal y espacial de larvas de
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Bak, R.P.M.; Nieuwland, G.; Meesters, H.W.G.
2009-01-01
Linear extension of branches in the same Acropora palmata (Lamarck, 1816) population in Curaçao was measured, employing exactly the same methods, in 1971-1973 and in 2002-2004, and the resulting coral growth rates are compared. Linear growth shows the same pattern over seasons in both periods with
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Spotted knapweed (SKW) (Centaurea maculosa Lamarck) is a non-indigenous species that is invasive over large areas in the U.S., especially in the western U. S. and Canada. It has been estimated that infestations of SKW cause $42 million in direct and indirect economic losses annually and the weed cou...
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African Journals Online (AJOL)
Items 1 - 50 of 175 ... Vol 18, No 2 (2009), A mesocosm analytical study on the ecological interactions of certain benthos in response to the biodeposition and bioturbation activities of the freshwater mussel Lamellidens marginalis (Lamarck), Abstract. VI Paul, P Jayakumar, N Jothivel, N Susithra. Vol 17, No 1 (2008), A Rapid ...
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Trophic relationships between macroinvertebrates and fish in a pampean lowland stream (Argentina
Directory of Open Access Journals (Sweden)
María V. López van Oosterom
2013-03-01
Full Text Available The diet and trophic relationships between the macroinvertebrates Phyllogomphoides joaquini Rodrigues Capítulo, 1992 and Coenagrionidae (Odonata, Chironomidae (Diptera, Diplodon delodontus (Lamarck, 1919 (Bivalvia: Hyriidae, and Pomacea canaliculata (Lamarck, 1822 (Gastropoda: Ampulariidae and the fishes Pimelodella laticeps Eigenmann, 1917 (Heptapteridae and Bryconamericus iheringii (Boulenger, 1887 (Characidae in a temperate lowland lotic system in Argentina were assessed on the basis of gut contents and stable-isotope analyses. The feeding strategies were analyzed by the AMUNDSEN method. Relative food items contribution for the taxa studied indicated a generalist-type trophic strategy. In macroinvertebrates, in general, the values of stable isotope confirmed the result of the analysis of gut contents. With the fish, stable-isotope analysis demonstrated that both species are predators, although B. iheringii exhibited a more omnivorous behaviour. These feeding studies allowed us to determine the trophic relationships among taxa studied. Detritus and diatoms were a principal source of food for all the macroinvertebrates studied. In La Choza stream the particulate organic matter is a major no limited food resource, has a significant influence upon the community.
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Epigenesis by experience: Romantic empiricism and non-Kantian biology.
Goldstein, Amanda Jo
2017-12-13
Reconstructions of Romantic-era life science in general, and epigenesis in particular, frequently take the Kantian logic of autotelic "self-organization" as their primary reference point. I argue in this essay that the Kantian conceptual rubric hinders our historical and theoretical understanding of epigenesis, Romantic and otherwise. Neither a neutral gloss on epigenesis, nor separable from the epistemological deflation of biological knowledge that has received intensive scrutiny in the history and philosophy of science, Kant's heuristics of autonomous "self-organization" in the third Critique amount to the strategic capture of epigenesis from nature, for thought, in thought's critical transcendence of nature. This essay looks to Jean-Baptiste Lamarck and his English contemporary Erasmus Darwin to begin to reconstruct the rigorously materialist, naturalist, and empiricist theories of epigenesis (still) marginalized by Kantian argumentation. As theorists of environmental and social collaboration in the ontogeny of viable forms, Lamarck and Darwin illuminate features of our own epigenetic turn obscured by the rhetoric of "self-organization," allowing us to glimpse an alternative Romantic genealogy of the biological present.
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Molecular phylogeny of extant Holothuroidea (Echinodermata).
Miller, Allison K; Kerr, Alexander M; Paulay, Gustav; Reich, Mike; Wilson, Nerida G; Carvajal, Jose I; Rouse, Greg W
2017-06-01
Sea cucumbers (Holothuroidea) are a morphologically diverse, ecologically important, and economically valued clade of echinoderms; however, the understanding of the overall systematics of the group remains controversial. Here, we present a phylogeny of extant Holothuroidea assessed with maximum parsimony, maximum likelihood, and Bayesian approaches using approximately 4.3kb of mt- (COI, 16S, 12S) and nDNA (H3, 18S, 28S) sequences from 82 holothuroid terminals representing 23 of the 27 widely-accepted family-ranked taxa. Currently five holothuroid taxa of ordinal rank are accepted. We find that three of the five orders are non-monophyletic, and we revise the taxonomy of the groups accordingly. Apodida is sister to the rest of Holothuroidea, here considered Actinopoda. Within Actinopoda, Elasipodida in part is sister to the remaining Actinopoda. This latter clade, comprising holothuroids with respiratory trees, is now called Pneumonophora. The traditional Aspidochirotida is paraphyletic, with representatives from three orders (Molpadida, Dendrochirotida, and Elasipodida in part) nested within. Therefore, we discontinue the use of Aspidochirotida and instead erect Holothuriida as the sister group to the remaining Pneumonophora, here termed Neoholothuriida. We found four well-supported major clades in Neoholothuriida: Dendrochirotida, Molpadida and two new clades, Synallactida and Persiculida. The mapping of traditionally-used morphological characters in holothuroid systematics onto the phylogeny revealed marked homoplasy in most characters demonstrating that further taxonomic revision of Holothuroidea is required. Two time-tree analyses, one based on calibrations for uncontroversial crown group dates for Eleutherozoa, Echinozoa and Holothuroidea and another using these calibrations plus four more from within Holothuroidea, showed major discrepancies, suggesting that fossils of Holothuroidea may need reassessment in terms of placing these forms with existing crown clades. Copyright © 2017 Elsevier Inc. All rights reserved.
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Echinoderm Biodiversity in the Takofi Coastal Waters, Moti Island, North Maluku
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Eddy Yusron
2006-04-01
Full Text Available A total of 22 echinoderm species were found in Takofi waters, North Maluku. They were represented by 6 species of holothuroidea, 4 species of asteroidea, 5 species of echinoidea and 7 species of ophiuroidea. The Ophiuroidea were relatively common in seagrass area. The quantitative analysis on the abundance data revealed the highest diversity index of faunal assemblage at station II (H'=1.19. The highest evenness index was exhibited by the echinoderms from station III (J = 0.99, while the highest species richness was represented by them from station I (D = 1.22.
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Structural analysis of the α subunit of Na(+)/K(+) ATPase genes in invertebrates.
Thabet, Rahma; Rouault, J-D; Ayadi, Habib; Leignel, Vincent
2016-01-01
The Na(+)/K(+) ATPase is a ubiquitous pump coordinating the transport of Na(+) and K(+) across the membrane of cells and its role is fundamental to cellular functions. It is heteromer in eukaryotes including two or three subunits (α, β and γ which is specific to the vertebrates). The catalytic functions of the enzyme have been attributed to the α subunit. Several complete α protein sequences are available, but only few gene structures were characterized. We identified the genomic sequences coding the α-subunit of the Na(+)/K(+) ATPase, from the whole-genome shotgun contigs (WGS), NCBI Genomes (chromosome), Genomic Survey Sequences (GSS) and High Throughput Genomic Sequences (HTGS) databases across distinct phyla. One copy of the α subunit gene was found in Annelida, Arthropoda, Cnidaria, Echinodermata, Hemichordata, Mollusca, Placozoa, Porifera, Platyhelminthes, Urochordata, but the nematodes seem to possess 2 to 4 copies. The number of introns varied from 0 (Platyhelminthes) to 26 (Porifera); and their localization and length are also highly variable. Molecular phylogenies (Maximum Likelihood and Maximum Parsimony methods) showed some clusters constituted by (Chordata/(Echinodermata/Hemichordata)) or (Plathelminthes/(Annelida/Mollusca)) and a basal position for Porifera. These structural analyses increase our knowledge about the evolutionary events of the α subunit genes in the invertebrates. Copyright © 2016 Elsevier Inc. All rights reserved.
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Sea urchins, their predators and prey in SW Portugal
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Nuno Mamede
2014-06-01
Full Text Available Sea urchins play a key role structuring benthic communities of rocky shores through an intense herbivory. The most abundant sea urchin species on shallow rocky subtidal habitats of the SW coast of Portugal is Paracentrotus lividus (Echinodermata: Echinoidea. It is considered a key species in various locations throughout its geographical distribution by affecting the structure of macroalgae communities and may cause the abrupt transformation of habitats dominated by foliose algae to habitats dominated by encrusting algae - the urchin barrens. The removal of P. lividus predators by recreational and commercial fishing is considered a major cause of this phenomenon by affecting the trophic relationships between predators, sea urchins and algae communities. Marine protected areas (MPAs usually lead to the recovery of important predator species that control sea urchin populations and restore habitats dominated by foliose macroalgae. Therefore, MPAs provide a good opportunity to test cascading effects and indirect impacts of fishing at the ecosystem level. The ecological role of P. lividus was studied on rocky subtidal habitats of the SW coast of Portugal (Alentejo considering three trophic levels: population of P. lividus, their predators (fish and shellfish and their prey (macroalgae communities. Several studies were conducted: (1 a non-destructive observational study on the abundance and distribution patterns of P. lividus, their predators and preys, comparing areas with different protection; (2 a manipulative in situ study with cages to assess the role of P. lividus as an herbivore and the influence of predation; (3 a descriptive study of P. lividus predators based on underwater filming; (4 and a study of human perception on these trophic relationships and other issues on sea urchin ecology and fishery, based on surveys made to fishermen and divers. Subtidal studies were performed with SCUBA diving at 3-12 m deep. Results indicate that in the
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Holothurian (Echinodermata) Diversity in the Glorieuses Archipelago
African Journals Online (AJOL)
Keywords: Holothuria, Glorieuses Islands, Western Indian Ocean, occurrence, diversity, coral reefs. Abstract—Due to their isolation, ... the Mozambique Channel (Western Indian Ocean). Inventories of several taxa, including the ... associated sandbars that emerge at low tide, complete the archipelago, with a land surface.
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Roberto A. Uribe
2012-10-01
Full Text Available Argopecten purpuratus (Lamarck, 1819 and Mesodesma donacium (Lamarck, 1818 are bivalves that inhabit the Humboldt Current Upwelling Ecosystem. They have contrasting biogeographical origins, suggesting that their responses to exogenous factors should differ. Using circular statistics, we examine synchrony/asynchrony in the reproductive cycle between populations of each species. The results indicate that there is reproductive asynchrony in both species along their distributional range. However, there was synchrony for A. purpuratus in several location-pairs, including Paita-Chimbote, Chimbote-Callao, Callao-Pisco and Pisco-Antofagasta. For M. donacium, there were only two synchronic groups: Camaná-Capellanía-Mehuín and Hornitos-Peñuelas-Longotoma-La Ligua-Cucao-Quilanlar. A. purpuratus showed gametogenenic activity throughout the year. In contrast, M. donacium showed strong seasonality, with gametogenesis in winter and spawning in spring/summer. In conclusion, the patterns observed for these sympatric species suggest that on a large scale the reproductive cycles follow the expected patterns for the contrasting biogeographic origin of each species, so it could be argued that they are modulated by endogenous factors. However, at a local scale, the reproductive cycles of these species show variation, likely determined by local oceanographic or hydrographic processes.
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Loison, Laurent; Gayon, Jean; Burian, Richard M
2017-02-01
This article shows how Lamarckism was essential in the birth of the French school of molecular biology. We argue that the concept of inheritance of acquired characters positively shaped debates surrounding bacteriophagy and lysogeny in the Pasteurian tradition during the interwar period. During this period the typical Lamarckian account of heredity treated it as the continuation of protoplasmic physiology in daughter cells. Félix d'Hérelle applied this conception to argue that there was only one species of bacteriophage and Jules Bordet applied it to develop an account of bacteriophagy as a transmissible form of autolysis and to analyze the new phenomenon of lysogeny. In a long-standing controversy with Bordet, Eugène Wollman deployed a more morphological understanding of the inheritance of acquired characters, yielding a particulate, but still Lamarckian, account of lysogeny. We then turn to André Lwoff who, with several colleagues, completed Wollman's research program from 1949 to 1953. We examine how he gradually set aside the Lamarckian background, finally removing inheritance of acquired characters from the resulting account of bacteriophagy and lysogeny. In the conclusion, we emphasize the complex dual role of Lamarckism as it moved from an assumed explanatory framework to a challenge that the nascent molecular biology had to overcome.
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Lamarck and the adaptive conservation of life
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Galera, Andrés
2009-12-01
Full Text Available This paper studies Lamarck’s evolutionary thought through four analytic elements. Firstly, Lamarckian construction of a founding evolutionary archetype. Secondly, the interpretation of nature as a material system where the organic change represents a continuous process aimed at the adaptative conservation of life. Thirdly, the definition of a genealogical process on the origin of species which identifies the natural method. Fourthly, the redefinition of the concept of species applying the arguments of temporary relativity and individual instability.
En este artículo se estudia el ideario evolucionista lamarckiano desarrollando cuatro elementos analíticos. Primero, la elaboración de un arquetipo evolutivo fundacional. Segundo, la interpretación de la naturaleza como un sistema material donde el cambio orgánico da sentido a un proceso continuo dirigido a la conservación de la vida. Tercero, la definición de un principio genealógico sobre el origen de las especies que identifica el método natural. Cuarto, la reformulación del concepto de especie utilizando los argumentos de relatividad temporal e inestabilidad individual. -
Digital Repository Service at National Institute of Oceanography (India)
Kumbhar, J; Rivonker, C
konkanensis (Melvill 1893) and Purpura bufo Lamarck 1822 from Goa are described for the first time using SEM photographs. Keywords: Muricidae, Goa, new record, taxonomic diagnosis, radula, SEM. 190 J.V. Kumbhar and C.U. Rivonker / Turk. J. Fish... optical zoom). The specimens were subsequently identified up to species Figure 1. Map of study area indicating sampling sites J.V. Kumbhar and C.U. Rivonker / Turk. J. Fish. Aquat. Sci. 189-197 (2012) 191...
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Paola Belcari
2002-06-01
Full Text Available Information on distribution, abundance and size composition of the two octopods Eledone cirrhosa and E. moschata was obtained from the MEDITS trawl surveys, carried out in a wide area of the Mediterranean basin from 1994 to 1999. Both species showed a wide geographic distribution, as they were collected in all the major areas investigated. E. cirrhosa showed a wide depth distribution, down to the 800 m isobath, while E. moschata was mostly restricted to within 200 m. Further analysis on spatio-temporal basis with a Generalised Linear Model, evidenced that differences among major areas, depth strata and their interaction were always significant. In the case of E. cirrhosa, differences among years and year-major area interaction were also significant. Two cohorts can be singled out in the size frequency distributions of E. cirrhosa, whereas only one mode can be clearly distinguished in most of the length distributions of E. moschata.
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Is evolution Darwinian or/and Lamarckian?
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Wolf Yuri I
2009-11-01
Full Text Available Abstract Background The year 2009 is the 200th anniversary of the publication of Jean-Bapteste Lamarck's Philosophie Zoologique and the 150th anniversary of Charles Darwin's On the Origin of Species. Lamarck believed that evolution is driven primarily by non-randomly acquired, beneficial phenotypic changes, in particular, those directly affected by the use of organs, which Lamarck believed to be inheritable. In contrast, Darwin assigned a greater importance to random, undirected change that provided material for natural selection. The concept The classic Lamarckian scheme appears untenable owing to the non-existence of mechanisms for direct reverse engineering of adaptive phenotypic characters acquired by an individual during its life span into the genome. However, various evolutionary phenomena that came to fore in the last few years, seem to fit a more broadly interpreted (quasiLamarckian paradigm. The prokaryotic CRISPR-Cas system of defense against mobile elements seems to function via a bona fide Lamarckian mechanism, namely, by integrating small segments of viral or plasmid DNA into specific loci in the host prokaryote genome and then utilizing the respective transcripts to destroy the cognate mobile element DNA (or RNA. A similar principle seems to be employed in the piRNA branch of RNA interference which is involved in defense against transposable elements in the animal germ line. Horizontal gene transfer (HGT, a dominant evolutionary process, at least, in prokaryotes, appears to be a form of (quasiLamarckian inheritance. The rate of HGT and the nature of acquired genes depend on the environment of the recipient organism and, in some cases, the transferred genes confer a selective advantage for growth in that environment, meeting the Lamarckian criteria. Various forms of stress-induced mutagenesis are tightly regulated and comprise a universal adaptive response to environmental stress in cellular life forms. Stress-induced mutagenesis
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The holothurian (Echinodermata) diversity of the Glorieuses Islands ...
African Journals Online (AJOL)
Glorieuses archipelago is one of the Eparses Islands, French islands scattered in the Mozambique Channel (Western Indian Ocean). ... In November 2012, a multidisciplinary team explored the reef slopes of the island by scuba diving down to 20 meters (10 sites), and the reef flats at low tide (12 sites) collecting specimens ...
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DOMINGO A. LANCELLOTTI
2000-03-01
Full Text Available La diversidad de macroinvertebrados marinos ha recibido una atención creciente, no obstante, con un escaso tratamiento en el contexto biogeográfico. Este estudio analiza los registros de 1.601 especies de macroinvertebrados bentónicos pertenecientes a: Demospongiae, Anthozoa, Polychaeta, Mollusca, Crustacea, Echinodermata y Ascideacea, agrupados en 10 zonas y tratados desde una perspectiva zoogeográfica. Mollusca (611 especies, Polychaeta (403 y Crustacea (370 corresponden a los grupos mejor representados a lo largo de la costa chilena, determinantes en el patrón global de la biodiversidad. Este aumenta suavemente de norte a sur, interrumpido por máximos que sugieren esfuerzos diferenciales de estudio más que un comportamiento natural de la biodiversidad. El grado de agrupamiento entre las zonas muestra las tres unidades biogeográficas definidas recientemente por Lancellotti & Vásquez. Este arreglo, que representa lo exhibido por los grupos más diversos, se ve alterado en los grupos menos representados donde las diferencias obedecen al patrón de afinidades mostradas por las zonas comprendidas dentro de la Región Templada Transicional. El quiebre zoogeográfico alrededor de los 41º S, sugerido largamente en la literatura, sólo ocurre en Echinodermata y Demospongiae, evidenciando en los otros taxa la existencia de un área de transición entre los 35º y 48º S, caracterizada por un reemplazo gradual de especies. Dentro de las regiones la biodiversidad muestra homogeneidad, contrario al endemismo, el que alcanza un máximo de 52% en la Región Templada Fría y que parece ser consecuencia del alto número de especies con registros únicos (38,2% de especies citadas para una sóla zona. Esto sugiere un desconocimiento de los macroinvertebrados chilenos (distribución y diversidad, sobrestimando el endemismo regional y distorsionando los patrones locales de biodiversidadThe diversity of marine macroinvertebrates has received increasing
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Eduardo Ríos-Jara
2013-03-01
Full Text Available Cuarenta especies de equinodermos fueron recolectadas en las zonas intermareal y submareal somero de 14 sitios de bahía Chamela. Destacan 7 nuevos registros para la costa de Jalisco. Los análisis de escalonamiento multidimensional no métrico y el índice de similitud de Jaccard permitieron identificar grupos y entidades aisladas de acuerdo a la contribución y frecuencia de las especies de 4 clases de equinodermos en los sitios de la bahía y en otras localidades del Pacífico tropical mexicano (PTM. La mayor similitud se presentó con las localidades del golfo de California. Los índices de distinción taxonómica promedio (Δ+ y su variación (Λ+ fueron utilizados para analizar la diversidad de equinodermos en los niveles de especie, género, familia, orden y clase para cada sitio de la bahía y para distintas localidades del PTM de acuerdo al número de jerarquías taxonómicas de alto orden y la variabilidad en su diversidad taxonómica. La riqueza de especies de Chamela representa el 20% de la diversidad total de equinodermos de las zonas intermareal y submareal somero del PTM, lo que indica su importancia en la contribución a la diversidad taxonómica de la región.Forty species of echinoderms were collected in the intertidal and shallow subtidal zones of 14 sites of bahía Chamela. Of particular importance are 7 new records of species for the coast of Jalisco. A nonmetric multidimensional scaling analysis and the Jaccard's similarity index identified different groups and isolated entities according to the contribution and the frequency of species of 4 classes of echinoderms in the bay and in other localities of the Mexican Tropical Pacific (MTP. The highest similarity of species was with the localities of the Gulf of California. The indices of average taxonomic distinctness (Δ+ and the variation in the taxonomic distinctness (Λ+ were estimated to analyze the diversity of echinoderms at the taxonomic levels of species, genus, family, order and class for each site within the bay and for some localities of the MTP according to the number of higher taxonomic hierarchies and the variability of its taxonomic diversity. The species richness of bahía Chamela represents 20% of the total diversity of echinoderms of the intertidal and shallow subtidal zones of the MTP; this is an indicator of its importance to the contribution of the taxonomic diversity of this region.
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Chemotaxonomic study of the demosponge Cinachyrella cavernosa (Lamarck)
Digital Repository Service at National Institute of Oceanography (India)
Wahidullah, S.; Naik, B.G.; Al-Fadhli, A.A
previously been identified in Cinachyrella australiensis. To our knowledge, this is the first report of 4α-methyl gorgostanol from a sponge and DPA from a marine source. The probable origin and chemotaxonomic importance of some of the metabolites is discussed...
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S. M. Perold
1988-10-01
Full Text Available R. nigrella DC. (Lamarck & De Candolle 1815, with which R. capensis auct. non Steph.: S. Amell (1952, 1963, is conspecific, is now also recognized from southern Africa. The thallus is brown marginally and dorsally and has shiny black scales with smooth margins at which coloured and hyaline cells alternate irregularly. Arnell's (1961 records of R. capensis Steph. from the Canary Islands are to be regarded as erroneous. R. capensis Steph. (Stephani in Brunnthaler 1913 is now placed in synonymy under R. limbata Bisch.
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Hossfeld, Uwe; Olsson, Lennart
2013-12-01
It is well known that the contribution of Alfred Russell Wallace (1823-1913) to the development of the "Darwinian" principle of natural selection has often been neglected. Here we focus on how the three anniversaries to celebrate the origin of the Darwin-Wallace theory in Germany in 1909, in 1959 in the divided country, as well as in 2009, have represented Charles Robert Darwin's and Alfred Russell Wallace's contributions. We have analyzed books and proceedings volumes related to these anniversaries, and the main result is that Wallace was almost always ignored, or only mentioned in passing. In 1909, Ernst Haeckel gave a talk in Jena, later published under the title The worldview of Darwin and Lamarck (Das Weltbild von Darwin und Lamarck), but not as the Darwin-Wallace concept. Haeckel mentions Wallace only once. In two important proceedings volumes from the 1959 anniversaries, Wallace was ignored. The only fair treatment of Wallace is given in another book, a collection of documents edited by Gerhard Heberer, for which the author selected nine key documents and reprinted excerpts (1959). Three of them were articles by Wallace, including the Sarawak- and Ternate-papers of 1855 and 1858, respectively. An analysis of the dominant themes during the celebrations of 2009 shows that none of the six topics had much to do with Wallace and his work. Thus, the tendency to exclude Alfred Russell Wallace is an international phenomenon, and largely attributable to the "Darwin industry".
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Sensorial, physical and chemical evaluation of bio-fortified Ipomoea batatas
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Mara N.G. Santos
2014-08-01
Full Text Available Context: Bio-fortified sweet potato, Ipomoea batatas (L. Lamarck beta-carotene rich, has been included in the most vulnerable population’s diet with the purpose of reducing health disturbances associated with hipovitaminosis. Aims:To evaluate a physical and chemical analysis of total carotenes and beta-carotene and to determine the antioxidant potential as well as to carry out a sensorial analysis of the bio-fortified Ipomoea batatas (L. Lamarck (BDB in nature and processed. Methods: BDB was processed as sweet (in natura, paste and syrup and physicochemical characteristics were compared, total carotenoids, beta-carotene, antioxidant activity (DPPH and microbiological and sensory analyses were performed. Results:The analysis of total carotenoids, beta-carotene and anti-oxidant potential showed the following results: BDB in nature – 11.81 mg/100 g/440.5 mg/100 g/26.30%; sweet paste – 0.61 mg/100 g/53.5 mg/100 g/53.40% and savored syrup – 0.85 mg/100 g/46.0 mg/100 g/14.30%. The methods of conservation avoided the coliforms growth at 35 and 45°C, Staphylococcus coagulasa positivo, Bacillus cereus and Salmonella in all elaborated candies. The sensorial analysis didn’t detect significant differences among the syrup or paste. Conclusions: The conservation methods have an important function keeping the physical, chemical characteristics and sensorial of BDB, although they can influence in their chemical and nutritional composition, mainly in relation to the quantity of total carotenoids and beta-carotene.
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Catalog of taxa introduced by Luitfried Salvini-Plawen (1939-2014).
Affenzeller, Susanne; Steiner, Gerhard
2017-10-17
Luitfried Salvini-Plawen was one of the most distinguished researchers for molluscan phylogenetic systematics of the last decades. In his publications he described a total of 193 species: 134 Solenogastres, 34 Caudofoveata, 14 interstitial Gastropoda, one polyplacophoran and the remaining comprising Cnidaria, Priapulida, Kamptozoa, and Echinodermata. In addition, he introduced 47 genus-group names and 54 names for family-level and higher taxa. This catalog comprises lists of all taxon names published by Luitfried Salvini-Plawen. The catalog entries contain taxonomic information, original citations, type localities and type collections. It aims to facilitate further research on these and related taxa.
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Giorgio Forti
2013-01-01
Full Text Available La teoria dell’Evoluzione biologica alla luce delle conoscenze acquisite dalla biologia molecolare, dall’immunologia e dall’embriologia: la “mutazione adattativa”, sua scoperta nei batteri e sua realtà negli organismi superiori. Statistica degli eventi rari e “piano intelligente”. Eredità dei caratteri acquisiti durante l’epigenesi: Darwin e Lamarck. Struttura del cervello e mente umana: il ruolo dell’eredità biologica e quello di ambiente, apprendimento ed esperienze nella formazione ed evoluzione della mente personale. Arbitrarietà e ridondanza nell’evoluzione biologica e nell’evoluzione del linguaggio umano.
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Vecchi, Davide; Baravalle, Lorenzo
2015-01-01
This paper will critically assess Popper's evolutionary philosophy. There exists a rich literature on the topic with which we have many reservations. We believe that Popper's evolutionary philosophy should be assessed in light of the intriguing theoretical insights offered, during the last 10 years or so, by the philosophy of biology, evolutionary biology and molecular biology. We will argue that, when analysed in this manner, Popper's ideas concerning the nature of selection, Lamarckism and the theoretical limits of neo-Darwinism can be appreciated in their full biological and philosophical value.
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Seasonal changes in biochemical composition of Holothuria leucospilota (Echinodermata)
Digital Repository Service at National Institute of Oceanography (India)
Jayasree, V.; Parulekar, A.H.; Wahidullah, S.; Kamat, S.Y.
Biochemical composition of body wall and gonads of Holothuria leucospilota was analysed for protein, carbohydrate, lipid, ash, dry weight and calorific values and was discussed in relation to its spawning activities. Lipids constituted the major...
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Phylogeography of Holothuria (Halodeima inornata Semper, 1868 (Echinodermata: Holothuroidea
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Elba Prieto-Rios
2014-10-01
Full Text Available Genetic structure of the populations of H. inornata was evaluated and the barriers for genetic flux and historic processes were investigated. Samples were collected trying to cover the distribution range of the species, from Mexico to northern Perú. Based on COI sequences, 118 haplotypes from 220 specimens were detected; the differences between such haplotypes were due to 97 variable sites (21.41% of the 453 bp sequenced. A high haplotype diversity (h=0.979 and a moderate nucleotidic diversity were observed. The values of Fst, the exact test of population differentiation, and the molecular variance analysis (AMOVA were used in order to analyze the genetic differentiation. These analyses suggest the existence of two populations: northern, off the coasts of Sinaloa, Jalisco, Michoacán, Guerrero, and Oaxaca, and southern, off the coasts of Chiapas, El Salvador, Panamá and Perú. Historic events and oceanographic patterns may be the main factors determining dispersion and structure of Hi populations. It seems probable that the original population have extended first in the south and then northern. Besides, the split between these two populations may be due to several tectonic and oceanographic events constituting a barrier for H. inornata settling.
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Antarctic Starfish (Echinodermata, Asteroidea) from the ANDEEP3 expedition.
Danis, Bruno; Jangoux, Michel; Wilmes, Jennifer
2012-01-01
This dataset includes information on sea stars collected during the ANDEEP3 expedition, which took place in 2005. The expedition focused on deep-sea stations in the Powell Basin and Weddell Sea.Sea stars were collected using an Agassiz trawl (3m, mesh-size 500µm), deployed in 16 stations during the ANTXXII/3 (ANDEEP3, PS72) expedition of the RV Polarstern. Sampling depth ranged from 1047 to 4931m. Trawling distance ranged from 731 to 3841m. The sampling area ranges from -41°S to -71°S (latitude) and from 0 to -65°W (longitude). A complete list of stations is available from the PANGAEA data system (http://www.pangaea.de/PHP/CruiseReports.php?b=Polarstern), including a cruise report (http://epic-reports.awi.de/3694/1/PE_72.pdf).The dataset includes 50 records, with individual counts ranging from 1-10, reaching a total of 132 specimens.The andeep3-Asteroidea is a unique dataset as it covers an under-explored region of the Southern Ocean, and that very little information was available regarding Antarctic deep-sea starfish. Before this study, most of the information available focused on starfish from shallower depths than 1000m. This dataset allowed to make unique observations, such as the fact that some species were only present at very high depths (Hymenaster crucifer, Hymenaster pellucidus, Hymenaster praecoquis, Psilaster charcoti, Freyella attenuata, Freyastera tuberculata, Styrachaster chuni and Vemaster sudatlanticus were all found below -3770m), while others displayed remarkable eurybathy, with very high depths amplitudes (Bathybiaster loripes (4842m), Lysasterias adeliae (4832m), Lophaster stellans (4752m), Cheiraster planeta (4708m), Eremicaster crassus (4626m), Lophaster gaini (4560m) and Ctenodiscus australis (4489m)).Even if the number of records is relatively small, the data bring many new insights on the taxonomic, bathymetric and geographic distributions of Southern starfish, covering a very large sampling zone. The dataset also brings to light six species, newly reported in the Southern Ocean.The quality of the data was controlled very thoroughly, by means of on-board Polarstern GPS systems, checking of identification by a renowned specialist (Prof. Michel Jangoux, Université Libre de Bruxelles), and matching to the Register of Antarctic Marine Species (RAMS) and World Register of Marine Species (WoRMS). The data is therefore fit for completing checklists, for inclusion in biodiversity patterns analysis, or niche modeling. It also nicely fills an information gap regarding deep-sea starfish from the Southern Ocean, for which data is very scarce at this time. The authors may be contacted if any additional information is needed before carrying out detailed biodiversity or biogeographic studies.
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NEW TRIASSIC ASTEROIDEA (ECHINODERMATA SPECIMENS AND THEIR EVOLUTIONARY SIGNIFICANCE
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DANIEL B. BLAKE
2017-04-01
Full Text Available The Paleozoic-Mesozoic transition saw the disappearance of asteroid stem groups and the ascent of the crown group, but late Paleozoic and Triassic asteroids are rare and transition events are poorly documented. Three new Middle and Late Triassic specimens augment existing data; included are a specimen of Trichasteropsis weissmanni from Germany, a specimen of Trichasteropsis? sp. indet. from Italy, and a possible member of the extant Poraniidae from Slovenia. Presence of a small ossicle at the interbrachial midline and adjacent to the marginal series of the new T. weissmanni specimen is consistent with similar expressions not only of other trichasteropsids but also occurrence of two interbrachial ossicles in Paleozoic, stem-group asterozoans; presence is in turn consistent with a hypothesis of derivation of the axillary/odontophore coupling from two ossicles rather than direct derivation of the crown-group odontophore from a single stem-group axillary. Morphology of Trichasteropsis? sp. indet., including, for example, the evenly-tapering arms are reminiscent of those of diverse crown-group asteroids whereas the enlarged distal arms of T. weissmanni are unique, the morphology of T? sp. indet. thereby potentially indicative of a plesiomorphic, stemward positioning within the Trichasteropsiidae. The range of the Poraniidae is tentatively extended to the Carnian. Similarities shared by the Poraniidae and the Trichasteropsiidae suggest stemward positioning within crown-group diversification; however, known Triassic fossils do not appear closely related to extant taxa identified in recent molecular studies as basal within the crown-group. A temperate climate is suggested as preferred by the Triassic asteroids rather than a tropical, warmer one.
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The mitochondrial genome of Priapulus caudatus Lamarck (Priapulida: Priapulidae).
Webster, Bonnie L; Mackenzie-Dodds, Jacqueline A; Telford, Maximilian J; Littlewood, D Timothy J
2007-03-01
We sequenced and annotated the complete mitochondrial (mt) genome of the priapulid Priapulus caudatus in order to provide a source of phylogenetic characters including an assessment of gene order arrangement. The genome was 14,919 bp in its entirety with few, short non-coding regions. A number of protein-coding and tRNA genes overlapped, making the genome relatively compact. The gene order was: cox1, cox2, trnK, trnD, atp8, atp6, cox3, trnG, nad3, trnA, trnR, trnN, rrnS, trnV, rrnL, trnL(yaa), trnL(nag), nad1, -trnS(nga), -cob, -nad6, trnP, -trnT, nad4L, nad4, trnH, nad5, trnF, -trnE, -trnS(nct), trnI, -trnQ, trnM, nad2, trnW, -trnC, -trnY; where '-' indicates genes transcribed on the opposite strand. The gene order, although unique amongst Metazoa, shared the greatest number of gene boundaries and the longest contiguous fragments with the chelicerate Limulus polyphemus. The mt genomes of these taxa differed only by a single inversion of 18 contiguous genes bounded by rrnS and trnS(nct). Other arthropods and nematodes shared fewer gene boundaries but considerably more than the most similar non-ecdysozoan.
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Mass Extinctions of Pangea (Jean Baptiste Lamarck Medal Lecture)
Wignall, Paul B.
2017-04-01
The 80 million years of Earth history from middle of the Permian to the early Jurassic were some of the worst life ever experienced. The interval includes two mass extinctions that bracket the Triassic period and several lesser crises. It was to be nearly another 120 million years before another major crisis was to strike (this time it was the famous one that removed the dinosaurs). So what was so bad about the 80 million years and why was it so good afterwards? My talk will try to provide at least some of the answers. There are plenty of clues. Notably, the interval coincides with the presence of the Pangea supercontinent and all the extinctions coincided with the eruption of large igneous provinces (LIPs). Indeed, every LIP of this interval coincides with an extinction crisis, a perfect correlation that completely breaks down afterwards. However, getting from correlation to causation is far from straight forward. There are many unknowns - how much gas was released by the volcanism, how quickly and what type of gases were they? These are all questions under investigation. Most of the extinctions of Pangean time coincide with rapid global warming and extensive marine anoxia suggesting that greenhouse gas emissions linked to volcanism were an important extinction driver. For the most severe crises (Permo-Triassic and end-Triassic) losses occurred throughout the food chain all the way down to the primary producers of the oceans and across all habitats including terrestrial ecosystems. At the other end of the spectrum of disaster, the lesser extinctions (Toarcian, Smithian/Spathian) only affected marine invertebrates. The full panoply of catastrophe was played out during the Permo-Triassic mass extinction and has received the most attention. The record in South China shows that there were two phases of extinction. These straddle the boundary and show selective losses initially for shallow-water organisms that were susceptible to high temperatures and then for deeper-water dwellers that succumbed to expanding deep-water anoxia. The contemporary plant losses show a similar duration for extinction losses ( 60 kyr) but the ultimate cause of these extinctions is less clear. It is unlikely to have been directly attributable to greenhouse gases because warm and wet conditions on land are a good thing. A greenhouse is a good place for plants after all. Ozone destruction by halogen emissions followed by intense UV-B radiation is a more promising extinction agent. A key factor in the extinction vulnerability of Pangean life may lie in the subdued nature of carbon cycling in a supercontinent configuration. Feedback mechanisms such as enhanced silicate weathering in warmer, more humid conditions would be less effective because of the vast arid interiors. The burial of carbon in shelf seas would also be minimal because the area of shallow waters around the periphery of the supercontinent was at a Phanerozoic minimum. Once initiated, warmer temperatures would have led to increased rate of organic remineralisation. This may have been responsible the absence of terrestrial organic carbon burial during the most severe crises, further decreasing the ability to drawdown atmospheric carbon. This combination of causes would have produced a planet that was only weakly responsive to sudden influxes of greenhouse gases into the atmosphere. It was a bad time to endure LIP eruptions.
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Directory of Open Access Journals (Sweden)
Ângela Teresa Silva-Souza
2008-08-01
Full Text Available The bivalve mollusk Anodontites trapesialis has been indicated as an alternative source for aquaculture because it is considered a food of good nutritional value with a protein content close to that of fish. Its shells can be utilized as fertilizer and mixed to the food of domestic animals, and the nacre can be used to manufacture buttons and crafts. However, the larvae of A. trapesialis, which are the lasidium type, are obligatory parasites of freshwater fishes, and the introduction of this bivalve in fish farm tanks have caused trouble and losses for producers. Nothing is known, however, about their development in these environments. On the other hand, it should be pointed out that A. trapesialis is on Brazil’s list of species threatened with extinction. This article provides a compilation of information present in the literature, offering a detailed review, with the aim of presenting a general panorama of what is known about Anodontites trapesialis and its larval parasitism of fishes.O molusco bivalve, Anodontites trapesialis, tem sido indicado como fonte alternativa para a aqüicultura, por ser considerado um alimento de bom valor nutricional com um conteúdo protéico próximo ao do pescado. Suas conchas podem ser utilizadas como fertilizantes calcáreos e ser agregadas a alimentos de animais domésticos e o nácar pode ser utilizado para fabricar botões e artesanatos. No entanto, as larvas de A. trapesialis, que são do tipo lasidium, são parasitas obrigatórias de peixes de água doce e a introdução desse bivalve em tanques de piscicultura tem causado transtornos e prejuízos aos produtores. Nada se conhece, porém, sobre o seu desenvolvimento nesses ambientes. Por outro lado, ressalta-se que A. trapesialis consta da lista brasileira de espécies ameaçadas de extinção. No presente artigo são compiladas as informações presentes na literatura, em uma revisão detalhada, com o objetivo de apresentar o panorama geral do conhecimento acerca de Anodontites trapesialis e do parasitismo de peixes por suas larvas.
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[Role of helminth antigens in the abnormal mitosis of bone marrow cells in laboratory animals].
Sivkova, T N; Tatarnikova, N A; Berezhko, V K; Benediktov, I I
2013-01-01
The intraabdominal administration of somatic extracts of the cestodes Hydatigera taeniaformis Batsch 1786, Lamarck, 1816 and Diphyllobothrium latum Linnaeus, 1758 and the nematodes Anisakis simplex larva Rudolphi 1809, Toxocara canis Railliet et Henry, 1912 in albino mice proved that these helminths had a karyopathic effect on the bone marrow cells of the animals. The antigenic composition of these extracts was investigated using the agar gel immunodiffusion test. The antigenic composition of the parasites was ascertained to affect their karyopathic properties. The amount of antigens and their foreignness caused a marked karyopathic effect on the bone marrow cells of laboratory animals during intraabdominal administration.
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Directory of Open Access Journals (Sweden)
Svjetlana Krstulović Šifner
2009-09-01
Full Text Available Length-weight relationships, sex ratio, maturity patterns, reproductive outputs, fecundity and spawning period of the musky octopus Eledone moschata (Lamarck, 1798 in the northern and central Adriatic Sea are presented for the first time. Samples were collected on a monthly basis by commercial bottom trawls between October 2001 and June 2003. A total of 1552 specimens were analysed (779 males, 764 females, 9 undetermined. The overall sex ratio was close to 1:1, but during summer males were dominant. Length-weight relationships calculated for each sex and the whole sample showed negative allometric growth (b
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Peña Freire, Viviana; Afonso-Carrillo, Julio; de Clerck, Olivier; Barreiro, Rofolfo; Gil-Rodríguez, María C.; Viera-Rodríguez, Maria A.; Neto, Ana I.; Le Gall, Line
2013-01-01
XIX Simposio de Botánica Criptogámica, Las Palmas de Gran Canaria, 24-28 de junio de 2013. Después de las primeras contribuciones a la flora coralinal de la región macaronésica por parte de Lamarck (1815), Montagne (1840) y Viera (1868-1869), han sido unos pocos ficólogos los que han aportado nuevas especies para los diferentes archipiélagos que componen esta región (Foslie 1905, 1906, May 1912, Lemoine 1929). Aparte del componente endémico de su flora, otras especies citadas presentan una...
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Diversity assessment of echinoderms from Mudasalodai and Pazhayar in the southeast coast of India
Directory of Open Access Journals (Sweden)
Maheswaran Murugan
2016-02-01
Full Text Available Objective: To study the echinoderms diversity in Mudasalodai and Pazhayar landing centers during November 2012 to December 2014. Methods: All the collected echinoderm samples were stored at 4 °C until further use. Results: As many as 19 species of echinoderms were recorded in both stations and it belongs to 10 families, three classes such as Asteroidea, Echinoidea and Ophiuroidea. The percentage composition varied from 0.15% to 73%. The species diversity ranged from 1.031 to 2.6; species richness was from 1.02 to 4.06 and species evenness ranged from 0.93 to 0.99. K-dominance curve drawn paralleled the trend of diversity indices. Cluster and multidimensional scaling showed the similarity in echinoderms composition within the stations. Conclusions: The present investigation is evident that the echinoderm occurrence was predominant during the summer season and proved statistically by using SPSS Primer 6.0.
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Conservation and diversification of Msx protein in metazoan evolution.
Takahashi, Hirokazu; Kamiya, Akiko; Ishiguro, Akira; Suzuki, Atsushi C; Saitou, Naruya; Toyoda, Atsushi; Aruga, Jun
2008-01-01
Msx (/msh) family genes encode homeodomain (HD) proteins that control ontogeny in many animal species. We compared the structures of Msx genes from a wide range of Metazoa (Porifera, Cnidaria, Nematoda, Arthropoda, Tardigrada, Platyhelminthes, Mollusca, Brachiopoda, Annelida, Echiura, Echinodermata, Hemichordata, and Chordata) to gain an understanding of the role of these genes in phylogeny. Exon-intron boundary analysis suggested that the position of the intron located N-terminally to the HDs was widely conserved in all the genes examined, including those of cnidarians. Amino acid (aa) sequence comparison revealed 3 new evolutionarily conserved domains, as well as very strong conservation of the HDs. Two of the three domains were associated with Groucho-like protein binding in both a vertebrate and a cnidarian Msx homolog, suggesting that the interaction between Groucho-like proteins and Msx proteins was established in eumetazoan ancestors. Pairwise comparison among the collected HDs and their C-flanking aa sequences revealed that the degree of sequence conservation varied depending on the animal taxa from which the sequences were derived. Highly conserved Msx genes were identified in the Vertebrata, Cephalochordata, Hemichordata, Echinodermata, Mollusca, Brachiopoda, and Anthozoa. The wide distribution of the conserved sequences in the animal phylogenetic tree suggested that metazoan ancestors had already acquired a set of conserved domains of the current Msx family genes. Interestingly, although strongly conserved sequences were recovered from the Vertebrata, Cephalochordata, and Anthozoa, the sequences from the Urochordata and Hydrozoa showed weak conservation. Because the Vertebrata-Cephalochordata-Urochordata and Anthozoa-Hydrozoa represent sister groups in the Chordata and Cnidaria, respectively, Msx sequence diversification may have occurred differentially in the course of evolution. We speculate that selective loss of the conserved domains in Msx family
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William Keith Brooks and the naturalist's defense of Darwinism in the late-nineteenth century.
Nash, Richard
2015-06-01
William Keith Brooks was an American zoologist at Johns Hopkins University from 1876 until his death in 1908. Over the course of his career, Brooks staunchly defended Darwinism, arguing for the centrality of natural selection in evolutionary theory at a time when alternative theories, such as neo-Lamarckism, grew prominent in American biology. In his book The Law of Heredity (1883), Brooks addressed problems raised by Darwin's theory of pangenesis. In modifying and developing Darwin's pangenesis, Brooks proposed a new theory of heredity that sought to avoid the pitfalls of Darwin's hypothesis. In so doing he strengthened Darwin's theory of natural selection by undermining arguments for the inheritance of acquired characteristics. In later attacks on neo-Lamarckism, Brooks consistently defended Darwin's theory of natural selection on logical grounds, continued to challenge the idea of the inheritance of acquired characteristics, and argued that natural selection best explained a wide range of adaptations. Finally, he critiqued Galton's statistical view of heredity and argued that Galton had resurrected an outmoded typological concept of species, one which Darwin and other naturalists had shown to be incorrect. Brooks's ideas resemble the "biological species concept" of the twentieth century, as developed by evolutionary biologist Ernst Mayr and others. The late-nineteenth century was not a period of total "eclipse" of Darwinism, as biologists and historians have hitherto seen it. Although the "Modern Synthesis" refers to the reconciliation of post-Mendelian genetics with evolution by natural selection, we might adjust our understanding of how the synthesis developed by seeing it as the culmination of a longer discussion that extends back to the late-nineteenth century.
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Trophic ecology of deep-sea Asteroidea (Echinodermata) from eastern Canada
Gale, Katie S. P.; Hamel, Jean-François; Mercier, Annie
2013-10-01
Asteroids (sea stars) can be important predators in benthic communities and are often present in ecologically important and vulnerable deep-sea coral and sponge habitats. However, explicit studies on the trophic ecology of deep-sea asteroids are rare. We investigated the diets of seven species of deep-sea asteroid from the bathyal zone of Newfoundland and Labrador, eastern Canada. A multifaceted approach including live animal observations, stomach content analysis, and stable isotope analysis revealed the asteroids to be either top predators of megafauna or secondary consumers (mud ingesters, infaunal predators, and suspension feeders). The stable isotope signatures of Ceramaster granularis, Hippasteria phrygiana, and Mediaster bairdi are characteristic of high-level predators, having δ15N values 4.4‰ (more than one trophic level) above Ctenodiscus crispatus, Leptychaster arcticus, Novodinia americana, and Zoroaster fulgens. We present strong evidence that corals and sponges are common food items for two of the predatory species, C. granularis and H. phrygiana. During laboratory feeding trials, live H. phrygiana fed on several species of soft coral and C. granularis fed on sponges. Stomach content analysis of wild-caught individuals revealed sclerites from sea pens (e.g. Pennatula sp.) in the stomachs of both asteroid species; H. phrygiana also contained sclerites from at least two other species of octocoral and siliceous sponge spicules were present in the stomachs of C. granularis. The stomach contents of the secondary consumers contained a range of invertebrate material. Leptychaster arcticus and Ctenodiscus crispatus feed infaunally on bulk sediment and molluscs, Zoroaster fulgens is a generalist infaunal predator, and the brisingid Novodinia americana is a specialist suspension feeder on benthopelagic crustaceans. This study provides a foundation for understanding the ecological roles of bathyal asteroids, and suggests that some species may have the potential to be important modulators of deep-sea benthic communities.
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Lamarck y la conservación adaptativa de la vida
Galera, Andrés
2009-01-01
En este artículo se estudia el ideario evolucionista lamarckiano desarrollando cuatro elementos analíticos. Primero, la elaboración de un arquetipo evolutivo fundacional. Segundo, la interpretación de la naturaleza como un sistema material donde el cambio orgánico da sentido a un proceso continuo dirigido a la conservación de la vida. Tercero, la definición de un principio genealógico sobre el origen de las especies que identifica el método natural. Cuarto, la reformulación del concepto de es...
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Kersken, Daniel; Göcke, Christian; Brandt, Angelika; Lejzerowicz, Franck; Schwabe, Enrico; Anna Seefeldt, Meike; Veit-Köhler, Gritta; Janussen, Dorte
2014-10-01
Due to their high abundance and large body size sponges have a central position in Antarctic zoobenthos, where they form the most extensive sponge grounds of the world. Though research on Antarctic benthos communities is quite established, research on sponge-associated infauna communities is scarce. We analyzed associated infauna of fifteen individuals of the sponge species Mycale (Oxymycale) acerata Kirkpatrick, 1907 (Demospongiae: Mycalina), Rossella antarctica Carter, 1872 and R. racovitzae Topsent, 1901 (both Hexactinellida: Lyssacinosida). Samples were collected from the deep Ekström Shelf at 602 m in the South-Eastern Weddell Sea, Antarctica, during the ANT XXIV-2 (SYSTCO I) expedition of RV Polarstern. The number of species, α- and β-diversity and the significantly different species composition of infauna communities related to sponge species were calculated, the latter via cluster analysis. The sponge-associated infauna consisted of five phyla: Foraminifera, Nematoda, Polychaeta, Mollusca and Arthropoda. In total 11,463 infaunal specimens were extracted and we found at least 76 associated species. Highest values of α-diversity were calculated for a sample of R. antarctica with a Shannon-Index of 1.84 and Simpson-Index of 0.72 respectively. Our results of the cluster-analysis show significant differences between infauna communities and a unique species composition for single sponge species. Polychaetes of the genus Syllis Lamarck, 1818 were numerous in M. acerata and genera like Pionosyllis Malmgren, 1867 and Cirratulus Lamarck, 1801 were numerous in R. antarctica. Individuals of the amphipod species Seba cf. dubia Schellenberg, 1926 were often found in R. antarctica and R. racovitzae while Colomastix fissilingua Schellenberg, 1926 was frequent in samples of M. acerata. Molluscs were present in M. acerata and R. antarctica but absent in R. racovitzae.
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PATRICIO SANCHEZ R
2000-01-01
Postmetamorphic rays in Heliaster and Labidiaster originate in four `quadrants' between the five primary rays, and not normally in the madreporic interradius. The rays originate in one of two very definite sequences depending on the species. H. kubiniji and H. multiradiatus share one sequence, whereas H. canopus, H. helianthus and Labidiaster share the other sequence. Pycnopodia, Rathbunaster, Heliaster and Labidiaster add rays at far greater sizes and in a manner that is distinctive from oth...
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Foreign bodies; or, how did Darwin invent the symptom?
Rowlinson, Matthew
2010-01-01
Beginning with a discussion of the sources in Darwin's writing for Freud's theory of the hysterical symptom, this essay proceeds to a symptomatic reading of Darwin himself. With reference to "The Origin of Species," "The Descent of Man," and "The Expression of the Emotions," this essay shows that Darwin's theories of involuntary expressive behavior and of aesthetic preference in sexual selection are linked by their role in his understanding of racial difference and also by their reliance on the idea that learned habits can be inherited as instincts, a view often identified with Lamarck. They are thus at once theories of the foreign body and theories that appear as foreigners within the body of Darwin's work.
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Making Heredity Matter: Samuel Butler's Idea of Unconscious Memory.
Turbil, Cristiano
2018-03-01
Butler's idea of evolution was developed over the publication of four books, several articles and essays between 1863 and 1890. These publications, although never achieving the success expected by Butler, proposed a psychological elaboration of evolution (robustly enforced by Lamarck's philosophy), called 'unconscious memory'. This was strongly in contrast with the materialistic approach suggested by Darwin's natural selection. Starting with a historical introduction, this paper aspires to ascertain the logic, meaning and significance of Butler's idea of 'unconscious memory' in the post-Darwinian physiological and psychological Pan-European discussion. Particular attention is devoted to demonstrating that Butler was not only a populariser of science but also an active protagonist in the late Victorian psychological debate.
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Evolutionary Origin of Antibiotic Resistance, A Historical Perspective
Directory of Open Access Journals (Sweden)
Yamile Adriana Celis Bustos
2017-07-01
Full Text Available Antimicrobial resistance is a natural aspect of bacterial evolution that can result from mutations or acquisition of foreign genes. Various views on the origin of this resistance explain the ability of these organisms to acquire new features. Lamarck andDarwin’s theories of evolution have led to experiments designed to explore the origin of bacterial variation and the emergence of new features. These experiments show that antimicrobial resistance is related to mutations in chromosomal genes and/or transfer of extrachromosomal genetic elements that can be expressed based on the antibiotic pressure exerted. The main experiments and findings that seek to explain the phenomenon of antibiotic resistance are reviewed here in.
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Hale, Piers J
2010-01-01
During the British socialist revival of the 1880s competing theories of evolution were central to disagreements about strategy for social change. In News from Nowhere (1891), William Morris had portrayed socialism as the result of Lamarckian processes, and imagined a non-Malthusian future. H.G. Wells, an enthusiastic admirer of Morris in the early days of the movement, became disillusioned as a result of the Malthusianism he learnt from Huxley and his subsequent rejection of Lamarckism in light of Weismann's experiments on mice. This brought him into conflict with his fellow Fabian, George Bernard Shaw, who rejected neo-Darwinism in favour of a Lamarckian conception of change he called "creative evolution."
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Cadmium, Copper and Tributyltin effects on fertilization of Paracentrotus lividus (Echinodermata
Directory of Open Access Journals (Sweden)
Mirella Vazzana
2010-01-01
Full Text Available Marine environments are continuously being threatened by a large number of xenobi- otics from anthropogenic sources. The effect of chemical pollution on living organisms are numerous and may impair reproductive success of adults species of marine invertebrate and vertebrate through effects on gamete quality. Echinoderms are characterized by external fertilizzation and gametes, free of any type of protection, may be in contact with toxic substances so the reproductive success depends largely on the environment conditions. The purpose of this work is to assess the effects on the in vitro fertiliza- tion of exposure of sea urchin Paracentrotus lividus gametes to xenobiotic substances as CuSO4, CdCl2 and TBTCl. The effect of contaminant were assessed by two experimental set in which gametes were treated with different concentration (0, 10-3, 10-5 10-7 10-9 M of different substances as CdCl2, CuSO4 and TBTCl. The effects were evaluated as percentage of fertilization. The results showed that the gametes exposure to xenobiotic decreased the percentage of fertilization and that more sensitive to treatment were the sperm cells, propably because the toxic effect affected the motility of the sperm. In conclusion, the absence of fertilization (spermiotoxicity may submit the toxic effects of these substances to the level of body and may candidate the sea urchis as biosensors for the evaluation of environmental quality.
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Marine Flora and Fauna of the Northeastern United States. Echinodermata: Holothuroidea.
Pawson, David L.
This report is part of a subseries entitled "Marine Flora and Fauna of the Northeastern United States" which is designed for use by biology students, biologists, biological oceanographers and informed laymen. Contents of this report include: (1) Introduction; (2) Morphology; (3) Systematic Characters; (4) Examination Procedures; (5)…
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The northward expansion of Synaptula reciprocans (Echinodermata) in the Mediterranean Sea
DEFF Research Database (Denmark)
Ragkousis, Michail; Marmara, Dimitra; Filiz, Halit
2017-01-01
Synaptula reciprocans was reported in the Mediterranean Sea for the first time back in 1986. Since then there have been numerous reports, following the species' gradual expansion and establishment in the eastern Mediterranean basin. Here we report, by using citizen science methods, from the project...... titled "Is it Alien to you? Share it" of iSea, the most recent known expansion sites of S. reciprocans, including its new northern-most frontier. Furthermore, the provided photographic evidence testifies for possible interspecies relationships, for the first time....
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Epigenética, evolución y la sombra de Lamarck
Dressino, Vicente
2009-01-01
Desde la formulación por Waddington del término epigenética este campo disciplinar ha manifestado un desarrollo lento pero sostenido. Sin embargo, en los últimos veinte años se produjo, debido al progreso tecnológico y conceptual experimentado por la biología, un gran crecimiento que está cambiando muchos conceptos en diversos campos de la biomedicina y de la biología evolutiva. La herencia epigenética describe la transmisión de la información sobre la base de la expresión genética, a diferen...
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Lamarckism Or Fear Of The Other And His Exclusion | Ojomo | IFE ...
African Journals Online (AJOL)
The Republic of South Africa is the largest and most powerful of the nations situated in the southernmost part of Africa . It came into existence in 1910 through the union of the two British colonies of Cape of good Hope and Natal and the two former Africaner (Boer) republics of Orange free state and south African Republic of ...
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Directory of Open Access Journals (Sweden)
Haryo Triajie
2010-04-01
Full Text Available Teripang atau Timun laut (Echinodermata adalah salah satu jenis komoditi laut yang bernilai domestik maupun internasional sub sektor perikanan yang cukup potensial. Salah satu zat bioaktif yang terkandung dalam teripang adalah senyawa steroid. Penelitian ini bertujuan menentukan tingkat efektivitas ekstrak kasar daging teripang yang telah diformulasikan dalam air media pemeliharaan juvenile udang galah terhadap keberhasilan mendapatkan jantan fenotif. Hipotesa yang dipakai pada penelitian ini adalah bahwa masa aktif pemberian ekstrak kasar daging teripang hasil formulasi yang diberikan dalam air media, efektif dapat berpengaruh dalam perkembangan juvenil menjadi jantan fenotif. Metode perendaman dengan dosis ekstrak teripang 10 mg/L, 15 mg/L dan 25 mg/L, dapat menghasilkan populasi jantan lebih tinggi dari kontrol (kontrol negatif/tanpa perlakuan hormon. Kata Kunci : teripang, steroid, jantan fenotif
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Lighty, R. G.; MacIntyre, I. G.; Stuckenrath, R.
1982-10-01
A minimum sea-level curve for the past 10,000 years has been constructed on the basis of radiocarbon dates of Acropora palmata (Lamarck) samples from the shallow-water framework of both relict and modern reefs of the tropical western Atlantic. A. palmata framework is a reliable reference for reconstructing the history of late Quaternary sea levels owing to its restricted depth range (palmata framework, the ease of obtaining uncontaminated samples, and the minimal compaction of A. palmata reef facies. The minimum sea-level curve constructed in this study is useful not only in evaluating the reliability of present and future Holocene sea-level curves for the western Atlantic, but also in estimating paleo-water depths in the study of Holocene reef history of this area.
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Experiences of the Use of Bio monitors for Heavy Metal Pollution Control in Almendares River
International Nuclear Information System (INIS)
Olivares- Rieumont, S.; Lima, L.; De la Rosa, D.; Martinez, F.; Borroto, J.; Columbie, I.; Sanchez, M.J.
2003-01-01
Full Text: This work is the first approach to establish a monitoring system for heavy metals in the Almendares Vento Basin. This basin is the most important watershed of Havana City, which main river is the Almendares River, that with 42 km of length goes through 5 municipalities, where live more than 500,000 inhabitants. The river receives a large pollution loads from more than 50 pollution sources of Havana City. Inputs of toxic substances like heavy metals come from the industries located along the river and tributaries, the urban discharges and from important speedways in both shores of the river. In the work, concentrations of Cd, Pb, Zn, Cu, Ni, Co and Cr in sediments, water, gastropod species Tarebia granifera Lamarck, macrophyte Eichhornia Crassipes and fish from the specie Gambusia were evaluated at 14 stations during the dry season of 2003. Concentrations of copper and lead in water samples exceeded applicable guidelines for many of the sites monitored in the river basin. Heavy metals in sediments were analysed using three-stage sequential extraction procedure. In sediments high contents of studied metals were found in the bioavailable fraction. Some stations were highly polluted with all elements. Two main sources of pollution with heavy metals could be identified in the basin due to the higher concentration of most of the studied metals in the analized sampling stations. Pb concentrations were high in almost all the stations. Similar behaviour was found for the metal concentration in Eichhornia Crassipes roots, that appear to have an interesting potential as bio monitor of the pollution with heavy metals. Tarebia granifera Lamarck only could be found in 5 of the 14 stations monitored, and it presence is related with the quality of the river water. The magnitude of contamination was estimated by the comparison between local backgrounds and concentration of metals measured. Only high concentration of Zn were found in the Gambusia tissue, and no
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Directory of Open Access Journals (Sweden)
M. Habbib Khirzin
2015-05-01
Full Text Available Teripang merupakan salah satu echinodermata yang memiliki kandungan protein tinggi dan sekitar 70% dari proteinnya merupakan kolagen. Tujuan penelitian ini adalah untuk mengetahui aktivitas inhibitor Angiotensin Converting Enzyme (ACE dan antioksidan dari peptida kolagen teripang Gama (Stichopus variegatus. Ekstraksi kolagen dilakukan menggunakan asam asetat 0,5 M. Peptida kolagen diperoleh melalui hidrolisis kolagen menggunakan enzim pepsin dengan konsentrasi 0,1 U/g kolagen, selama 0; 30; 60; 90; 120; 180; dan 240 menit. Aktivitas inhibitor ACE dan antioksidan peptida kolagen diuji dengan metode spektroskopi. Kolagen yang dihasilkan memiliki rendemen 16,40% dengan berat molekul 130,33 kDa. Aktivitas inhibitor ACE tertinggi dihasilkan dari proses hidrolisis selama 180 menit dengan penghambatan sebesar 82,31%, sedangkan aktivitas antioksidan tertinggi dihasilkan oleh peptida kolagen dari hidrolisis kolagen selama 120 menit dengan nilai IC50 1,9 mg/ml.
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Males and females gonad fatty acids of the sea urchins and (Echinodermata)
Martínez-Pita , Inés; García , Francisco J.; Pita , María-Luisa
2009-01-01
Abstract The aim of this study was to analyze male and female gonad fatty acids of two sea urchin species, Paracentrotus lividus and Arbacia lixula, from the south coast of Spain. Additionally, we investigated possible differences between two locations. The ovaries of both species showed higher percentages of 14:0, 16:0, 16:1n-7, 18:2n-6, 18:3n-3 and 18:4n-3 than testes and lower levels of 18:0, 22:1n-9, 20:4n-6 and 22:5n-3. In P. lividus but not in A. lixula, the level of 20:5n-3 ...
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Directory of Open Access Journals (Sweden)
CT. Callil
Full Text Available The unionid Anodontites trapesilais (Lamarck, 1819 like most freshwater mussels is a parasite of fish. So it is trivial to assume that the availability of hosts is an important factor for the maintenance of unionoid populations. What seems obvious is not always so easy to demonstrate. This study proposes to investigate the effects of abiotic and biotic variables related to the incubation of larvae in A. trapesialis. For this, we estimate different biological indexes and try to capture the dimensionality of the fish, along with the temporal variation of environmental variables. From the application of a CCA, it was demonstrated that there was a synchronicity among the factors and variables proposed here, and we infer that the flood pulse acts as a synergistic factor in this process.
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Feeding preference of the sea urchin Lytechinus variegatus (Lamarck, 1816 on seaweeds
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Camilla Ferreira Souza
2008-09-01
Full Text Available Seaweeds exhibit different strategies to minimize the damage caused by herbivores and also to influence the feeding preference of these consumers. This study evaluated the feeding preference of the sea urchin Lytechinus variegatus through multiple-choice experiments using the seaweeds Caulerpa racemosa, Dictyota menstrualis, Osmundaria obtusiloba, Plocamium brasiliense, Sargassum sp., and Ulva sp. In order to verify the importance of morphological and chemical aspects on this feeding preference, two assay-types were carried out using live and powdered macroalgae, respectively. Two different methods were employed to analyze the results obtained: comparison between biomass losses versus autogenic changes, and inclusion of autogenic values in biomass loss through herbivory. In both experiments a clear differential consumption of certain species of seaweeds by L. variegatus was observed, in the following decreasing order of preference: C. racemosa ≈ Ulva sp. > O. obtusiloba ≈ Sargassum sp. > P. brasiliense > D. menstrualis. It was also verified that both methods of analysis used yielded similar results. According to the results obtained, feeding preference of L. variegatus is probably established by the defensive chemicals produced by P. brasiliense and D. menstrualis, and by morphological aspects of C. racemosa, Ulva sp., O. obtusiloba and Sargassum sp.As macroalgas apresentam diversos tipos de estratégias para minimizar os danos gerados por herbívoros que influenciam a preferência alimentar dos consumidores. Este estudo avaliou a preferência alimentar do ouriço-do-mar Lytechinus variegatus em experimentos de múltipla escolha utilizando as macroalgas bentônicas Caulerpa racemosa, Dictyota menstrualis, Osmundaria obtusiloba, Plocamium brasiliense, Sargassum sp., e Ulva sp. Para verificar a importância dos aspectos morfológicos e químicos na preferência, os ensaios foram realizados com algas vivas e em pó, respectivamente. Foram utilizados dois métodos distintos de análise de dados: comparação entre a perda de biomassa e as mudanças por autogenia, e a incorporação dos valores de autogenia à perda de biomassa por herbivoria. Em ambos os experimentos observou-se uma clara preferência de L. variegatus por certas espécies de macroalgas em relação a outras, em ordem decrescente de preferência: C. racemosa ≈ Ulva sp. > O. obtusiloba ≈ Sargassum sp. > P. brasiliense > D. menstrualis. Além disso, constatou-se que os dois métodos de análise produziram resultados muito similares. De acordo com os resultados, a preferência alimentar de L. variegatus é provavelmente condicionada pela química defensiva produzida por P. brasiliense e D. menstrualis e aspectos morfológicos presentes em C. racemosa, Ulva sp., O. obtusiloba e Sargassum sp.
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Therapeutic Significance of Loligo vulgaris (Lamarck, 1798) ink Extract: A Biomedical Approach
Nadarajah, Sri Kumaran; Vijayaraj, Radha; Mani, Jayaprakashvel
2017-01-01
Background: The squid ink extract is well known for its biomedical properties. Objective: In this study, squid Loligo vulgaris was collected from Tuticorin costal water, Bay of Bengal, India. Materials and Methods: Proximate composition of the crude squid ink was studied and found to have protein as the major component over lipid and carbohydrates. Further, bioactive fractions of squid ink were extracted with ethanol, and therapeutic applications such as hemolytic, antioxidant, antimicrobial, and in vitro anti-inflammatory properties were analyzed using standard methods. Results: In hemolytic assay, the squid ink extract exhibited a maximum hemolytic activity of 128 hemolytic unit against tested erythrocytes. In DPPH assay, the ethanolic extract of squid ink has exhibited an antioxidant activity of 83.5%. The squid ink was found to be potent antibacterial agent against the pathogens tested. 200 μL of L. vulgaris ink extract showed remarkable antibacterial activity as zone of inhibition against Escherichia coli (28 mm), Klebsiella pneumoniae (22 mm), Pseudomonas aeruginosa (21 mm), and Staphylococcus aureus (24 mm). The 68.9% inhibition of protein denaturation by the squid ink extract indicated that it has very good in vitro anti-inflammatory properties. The Fourier transform infrared spectroscopy analysis of the ethanolic extracts of the squid ink indicated the presence of functional groups such as 1° and 2° amines, amides, alkynes (terminal), alkenes, aldehydes, nitriles, alkanes, aliphatic amines, carboxylic acids, and alkyl halides, which complements the biochemical background of therapeutic applications. Conclusion: Hence, results of this study concluded that the ethanolic extract of L. vulgaris has many therapeutic applications such as antimicrobial, antioxidant, and anti-inflammatory activities. SUMMARY Squid ink is very high in a number of important nutrients. It’s particularly high in antioxidants for instance, which as well all know help to protect the cells and the heart against damage from free radicals. In the present study, the squid ink have antioxidant, anti-inflammatory and cytotoxic properties and can be considered as promising the developing the drugs. Abbreviations Used: DPPH: 2,2-diphenyl-1-picrylhydrazyl, FTIR: Fourier-transform infrared spectroscopy, BSA: Bovine Serum Albumin PMID:29333051
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Igor David da Costa
2009-01-01
Full Text Available Para caracterizar la biodiversidad de invertebrados bentónicos que componen la fauna asociada a la pesca de camarones en el puerto del Farol de Sao Thomé, costa norte del estado de Río de Janeiro, se realizaron 11 pescas mensuales en el año 2004 con redes de arrastre de fondo, cuya área de operaciones comprende 3-5 mn desde la línea de costa, entre 22°00'S y 22°20'S. Los datos registrados de cada taxon y/o especie se refieren a la frecuencia de ocurrencia, frecuencia numérica, biomasa, índice de Importancia Relativa y abundancia. En total se registraron 27 especies de invertebrados bentónicos de Porifera, Cnidaria, Mollusca, Annelida, Crustácea, Echinodermata y Bryozoa. Crustácea fue el más representativo, tanto en número de ejemplares de Petrochirus diogenes, Hepatus pudibundus y Callinectes ornatos, como en biomasa de P. diogenes y H. pudibundas. En términos de frecuencia de ocurrencia en los muéstreos, 11 especies (40,7% fueron constantes; 6 (22,2% accesorias y 10 (37,0% accidentales.In order to characterize the biodiversity of the benthic invertebrate by-catch associated with the shrimp fishery at Farol de Sao Thome harbor, northern Rio de Janeiro State, Brazil, in 2004, 11 monthly trawls were conducted using bottom trawl nets between 22°00'S and 22°20'S and from 3 to 5 nm from the shoreline. The analyzed data for each talon and/or species include frequency of occurrence, numeric frequency, biomass, index of Relative Importance, and abundance. In total, 27 benthic invertebrate species were recorded, including Peripheral, Cnidarians, Mollusk, Annelid, Crustacea, Echinodermata, and Bryozoa. The most representative group was Crustacea, both in number of specimens (Petrochirus diogenes, Hepatus pudibundus, Callinectes ornatus and in biomass (P. diogenes, H. pudibundus. In terms of the frequency of occurrence in the samples, 11 species (40.7% were constant, 6 species (22.2% were accessories, and 10 species (37.0% were by-catch.
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Phylogenetic study of the oxytocin-like immunoreactive system in invertebrates.
Mizuno, J; Takeda, N
1988-01-01
1. A phylogenetic study of oxytocin (OXT)-like immunoreactive cells was performed by the PAP method in the central nervous system of invertebrates. 2. The immunoreactivity was detected in the nerve cells of Hydra magnipapillata of the Coelenterata; Neanthes japonica and Pheretima communissima of the Annelida; Oncidium verrucosum, Limax marginatus and Meretrix lamarckii of the Mollusca; and Baratha brassica of the Arthropoda. 3. No immunoreactive cells were found in Bipalium sp. of the Platyhelminthes; Pomacea canaliculata, Aplysia kurodai, Bradybaena similaris and Achatina fulica of the Mollusca; and Gnorimosphaeroma rayi, Procambarus clarkii, Hemigrapsus sanguineus, Helice tridens and Gryllus bimaculatus of the Arthropoda; Asterina pectinifera of the Echinodermata; and Halocynthia roretzi of the Protochordata. 4. These results demonstrate that an OXT-immunoreactive substance is widely present not only in vertebrates but also in invertebrates. 5. OXT seems to have been introduced into these invertebrates at an early stage of their phylogenetic history.
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Mizuno, J; Takeda, N
1988-01-01
1. A phylogenetic study of arg-vasotocin (AVT)/arg-vasopressin (AVP)-like immunoreactive cells was performed by the PAP method in the central nervous system of invertebrates. 2. The immunoreactivity was detected in the nerve cells of Hydra magnipapillata of the Coelenterata; Neanthes japonica and Pheretima communissima of the Annelida; Pomacea canaliculata, Aplysia kurodai, Oncidium verrucosum, Bradybaena similaris, Achatina fulica, Limax marginatus and Meretrix lamarckii of the Mollusca; Gnorimosphaeroma rayi, Hemigrapsus sanguineus, Gryllus bimaculatus and Baratha brassicae of the Arthropoda; Asterina pectinifera of the Echinodermata; and Halocynthia roretzi of the Protochordata. 3. No immunoreactivity was detected in Bipalium sp. of the Platyhelminthes, or in Procambarus clarkii and Helice tridens of the Arthropoda. 4. From these results, it appears that AVT/AVP is a phylogenetically ancient peptide which is present in a wide variety of invertebrates. 5. The actions of AVT/AVP and its presence in invertebrates are discussed.
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Gluconeogenesis: An ancient biochemical pathway with a new twist.
Miyamoto, Tetsuya; Amrein, Hubert
2017-07-03
Synthesis of sugars from simple carbon sources is critical for survival of animals under limited nutrient availability. Thus, sugar-synthesizing enzymes should be present across the entire metazoan spectrum. Here, we explore the evolution of glucose and trehalose synthesis using a phylogenetic analysis of enzymes specific for the two pathways. Our analysis reveals that the production of trehalose is the more ancestral biochemical process, found in single cell organisms and primitive metazoans, but also in insects. The gluconeogenic-specific enzyme glucose-6-phosphatase (G6Pase) first appears in Cnidaria, but is also present in Echinodermata, Mollusca and Vertebrata. Intriguingly, some species of nematodes and arthropods possess the genes for both pathways. Moreover, expression data from Drosophila suggests that G6Pase and, hence, gluconeogenesis, initially had a neuronal function. We speculate that in insects-and possibly in some vertebrates-gluconeogenesis may be used as a means of neuronal signaling.
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Ricardo Bitter - Soto
1999-09-01
Full Text Available The benthic community associated with the turtlegrass Thalassia testudinum beds was analized at three localities of Morrocoy National Park, Venezuela. The localities were selected according to their exposure to the open sea : A (protected, B (intermediate and C (exposed. At each locality, a 20 x 20 m area was randomly chosen, delimited and divided into 400 1x1 m quadrats. Inside each, ten randomly selected quadrats/month were sampled during 13 consecutive months. At each site all macroinvertebrates and several physical variables were recorded, as well as leaf and rhizome biomass of T. testudinum. All parameters had a step- wise gradient from A through C: organic matter, carbon nitrogen, oxygen, salinity and temperature gradient was: ABC. Percentages of sand, silt and clay showed an inverse gradient; ASe analizó la comunidad bentónica asociada a Thalassia testudinum y su relación con algunos parámetros bióticos y abióticos, en tres localidades del Parque Nacional Morrocoy, Falcón-Venezuela; éstas fueron seleccionadas de acuerdo al grado de exposición al mar abierto: A(protegída, B (intermedia y C (expuesta. En cada localidad se demarcó un área de 20 x 20m, se muestrearon aleatoriamente 10cuadrantes/mes, (130 cuadrantes/localidad. Se efectuaron registros de oxígeno disuelto, salinidad, temperatura, porcentajes de materia orgánica, carbono y nitrógeno, textura del sedimento, biomasa foliar y de rizoma de T. testudinum. Todos los parámetros analizados presentaron un gradiente escalonado. Materia Orgánica, Carbono y Nitrógeno, Oxígeno disuelto, Salinidad y Temperatura presentaron el gradiente: ABC. Los porcentages de Arena, Limo y Arcilla presentaron un gradiente inverso. El patrón en la Diversidad, Equidad y Dominancia fue: BCA. La fauna colectada estuvo compuesta por los grupos: Coelenterata (Anthozoa, Polichaeta, Sipuncula, Molusca, Crustacea y Echinodermata. Se identificaron 15 especies de moluscos (gastrópodos y bivalvos, (3
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Did Jean François Barbe Anticipate Charles Darwin?
Drouin, Anne-Sophie; Drouin, Emmanuel; Pereon, Yann
2016-12-01
The publication of Charles Darwin's On the Origin of Species in 1859 is widely suppose to have initiated a revolution in science. In 1837, he broke with dogmatic fixism and argued that the adaptation of populations to their local environment was the cause of transmutation. Some contributors helped him start his reasoning: he indeed expressed his indebtedness to Samuel Rowley for having called his attention to Charles Wells' notions of natural selection. Darwin was certainly not the first to suggest the idea of evolution as an alternative to the creation of species by God. We report on a medical thesis published in 1837 being concluded by an unexpected and important statement related to the appearance of mammals on Earth. It remained unknown but it constitutes a link between the transformative thought of Lamarck and Geoffroy Saint Hilaire, and Darwin's work.
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Donald J. Colgan
2018-03-01
Full Text Available The hairy mussel Trichomya hirsuta (Lamarck, 1819 has disjunct known ranges in northeast Asia and Australia. There are substantial DNA sequence divergences for mitochondrial cytochrome c oxidase subunit I and 16S ribosomal RNA between specimens from these ranges showing that neither is likely to derive from a recent colonization. The most recent common ancestor of the observed haplotypes may have lived as long ago as the early Pliocene. It is, however, suggested here that the mussels from the two regions continue to be regarded, tentatively, as conspecific because intraspecific divergence of mitochondrial DNA sequences can be very high in Mytilidae. The present knowledge of fossil history suggests that the direction of colonization in Trichomya may have been from the Southern to the Northern Hemisphere in contrast with migrations of other genera of Mytilidae.
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Czech Academy of Sciences Publication Activity Database
Žítt, Jiří
2005-01-01
Roč. 26, č. 2 (2005), s. 225-237 ISSN 0195-6671 R&D Projects: GA ČR(CZ) GA206/01/1580 Institutional research plan: CEZ:AV0Z30130516 Keywords : Cretaceous * Asteroidea * New species Subject RIV: EG - Zoology Impact factor: 0.981, year: 2005
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Bruno C Vellutini
Full Text Available Sea biscuits and sand dollars diverged from other irregular echinoids approximately 55 million years ago and rapidly dispersed to oceans worldwide. A series of morphological changes were associated with the occupation of sand beds such as flattening of the body, shortening of primary spines, multiplication of podia, and retention of the lantern of Aristotle into adulthood. To investigate the developmental basis of such morphological changes we documented the ontogeny of Clypeaster subdepressus. We obtained gametes from adult specimens by KCl injection and raised the embryos at 26 degrees C. Ciliated blastulae hatched 7.5 h after sperm entry. During gastrulation the archenteron elongated continuously while ectodermal red-pigmented cells migrated synchronously to the apical plate. Pluteus larvae began to feed in 3 d and were 20 d old at metamorphosis; starved larvae died 17 d after fertilization. Postlarval juveniles had neither mouth nor anus nor plates on the aboral side, except for the remnants of larval spicules, but their bilateral symmetry became evident after the resorption of larval tissues. Ossicles of the lantern were present and organized in 5 groups. Each group had 1 tooth, 2 demipyramids, and 2 epiphyses with a rotula in between. Early appendages consisted of 15 spines, 15 podia (2 types, and 5 sphaeridia. Podial types were distributed in accordance to Lovén's rule and the first podium of each ambulacrum was not encircled by the skeleton. Seven days after metamorphosis juveniles began to feed by rasping sand grains with the lantern. Juveniles survived in laboratory cultures for 9 months and died with wide, a single open sphaeridium per ambulacrum, aboral anus, and no differentiated food grooves or petaloids. Tracking the morphogenesis of early juveniles is a necessary step to elucidate the developmental mechanisms of echinoid growth and important groundwork to clarify homologies between irregular urchins.
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Catarina Anjos
2014-06-01
Full Text Available The Portuguese oyster Crassostrea angulata shows great potential in oyster farming. In Europe, pure populations of this species were observed only in the southern coasts of Portugal and Spain, namely in Rio Sado, Rio Mira and Guadalquivir. The conservation of C. angulata populations is important in the context of production diversification and biodiversity preservation. In this way the zootechnological development for seed hatchery production is extremely important. Broodstock conditioning is a key step in the process of rearing bivalve in hatchery. Many factors regulate the reproductive cycle, being food the most important. However the influence of the nutritional quality of different phytoplankton on sexual maturation has been poorly explored. To evaluate the effects of different diets on C. angulata sexual maturity, broodstock were conditioned with different food regimes: Diet 1: bi-specific combination of Pavlova lutheri and Isochrysis galbana clone T-ISO (1:1; Diet 2: tri-specific combination of P. lutheri, I galbana clone T-ISO and Skeletonema constatum (1:1:1; Diet 3: bi-specific combination of S. constatum and Chaetoceros calcitrans (1:1 and Diet 4: tri-specific combination of P. lutheri, S. constatum and C. calcitrans (1:1:1. During conditioning, condition index and gonad histological analysis were performed. Results showed heterogeneity between diets. At the beginning of conditioning 60% of individuals were in resting (stage 0, 30% were males in early gametogenesis (stage I and 10% were females in mature stage (stage III. At the end of the conditioning, the most effective diet was the Diet 3 (60 % of mature oysters with a mean condition index value of 2.83±0.95. Whereas those fed with Diet 1 have an unsuccessfully gonadic development, with 80% of individuals in resting stage. Indeed, the condition index, in Diet 1 decreased during the conditioning period. The results obtained in this study reinforce the idea that the diatom microalgae group is essential in the conditioning of C. angulata broodstock. This work constitute an important first step in the hatchery C. angulata broodstock nutrition and a prerequisite for future work on improvement of broodstock conditioning and the optimization of feeding practices that will maximize the conditioning phase and minimize cost in aquaculture hatcheries.
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Ellen Silva Lago-Vanzela
2011-09-01
Full Text Available In Brazil, several little economically explored fruits have good potential as raw material for the agro-industry. This study aimed to produce and determine the physical-chemical and sensory characteristics of light jambolan jelly. This fruit has intense purple color, which gave the jellies - both standard and light - a quite attractive visual aspect. The light jellies exhibited similar physical-chemical characteristics to the ones developed through the conventional method and; with the proportion of sweeteners used, the caloric values of the formulations were reduced to the range of 41 to 53%, attending the requirements of the Brazilian legislation for this type of product. The sensory profile obtained for the 4 light formulations developed, clearly showed the tasters' preference for the jelly elaborated with the association of cyclamate and saccharin. Thus, the results revealed good perspectives for the application of this fruit in the food industry.
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Extraction and Characterization of Collagen from Sea Cucumber Flesh
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Alhana
2015-11-01
Full Text Available Sea cucumber (Stichopus variegatus is one of the Echinodermata phylum that grows along Indonesian coastal. Sea cucumber is potential source of collagen. The purposes of this research were to determine the optimal concentration of NaOH and CH3COOH solution in collagen production and analyze the physicochemical characteristics of collagen from S. variegatus. Yield of the collagen was 1.5% (based on wet weight basis, produced by pretreatment with NaOH 0,30%, hydrolysis with CH3COOH 0.10% and extracted using distilled water. Protein, moisture, and ash content of the collagen was 67.68%, 13.64%, and 4.15%, respectively. Collagen was extracted using distilled water at 45°C during 2h and still had triple helix structure ; pH 7.37 ; melting temperature 163.67°C and whiteness 69.25%. The major amino acid content of collagen were glycine, alanine, proline and glutamic acid.
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Exploring Canadian Echinoderm Diversity through DNA Barcodes.
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Kara K S Layton
Full Text Available DNA barcoding has proven an effective tool for species identification in varied groups of marine invertebrates including crustaceans, molluscs, polychaetes and echinoderms. In this study, we further validate its utility by analyzing almost half of the 300 species of Echinodermata known from Canadian waters. COI sequences from 999 specimens were assigned to 145 BINs. In most cases, species discrimination was straightforward due to the large difference (25-fold between mean intra- (0.48% and inter- (12.0% specific divergence. Six species were flagged for further taxonomic investigation because specimens assigned to them fell into two or three discrete sequence clusters. The potential influence of larval dispersal capacity and glacial events on patterns of genetic diversity is discussed for 19 trans-oceanic species. Although additional research is needed to clarify biogeographic patterns and resolve taxonomic questions, this study represents an important step in the assembly of a DNA barcode library for all Canadian echinoderms, a valuable resource for future biosurveillance programs.
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Romeo, Teresa; D'Alessandro, Michela; Esposito, Valentina; Scotti, Gianfranco; Berto, Daniela; Formalewicz, Malgorzata; Noventa, Seta; Giuliani, Silvia; Macchia, Simona; Sartori, Davide; Mazzola, Angelo; Andaloro, Franco; Giacobbe, Salvatore; Deidun, Alan; Renzi, Monia
2015-12-01
Contamination levels by plastic debris, trace elements and persistent organic pollutants were assessed and related to macrobenthic diversity within soft bottoms of Grand Harbour (Malta, Central Mediterranean). Sediment toxicity was evaluated by ecotoxicological method, deploying Bacteria (Vibrio fischeri), Echinodermata (Paracentrotus lividus) and Crustacea (Corophium orientale). Univariate analysis (Pearson's test) was used to test relationships between biodiversity indices, pollutants and grain size. A multivariate approach (PERMANOVA) was applied to investigate for any significant differences among sampling stations concerning plastic abundances and to test the relationship between infaunal abundances and pollutant concentrations (the BIOENV test). Significant differences in the plastic abundances were found between sampling stations. The lowest value for Shannon-Wiener biodiversity index was associated to the highest sediment pollution level. Multivariate analyses suggest that MBT and TBT were factors that most influenced macrozoobenthic abundance and biodiversity. The bivalve Corbula gibba and the introduced polychaete Monticellina dorsobranchialis were the most abundant found species.
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Ramachandra, Rashmi; Namburi, Ramesh B; Ortega-Martinez, Olga; Shi, Xiaofeng; Zaia, Joseph; Dupont, Sam T; Thorndyke, Michael C; Lindahl, Ulf; Spillmann, Dorothe
2014-02-01
Glycosaminoglycans (GAGs) isolated from brittlestars, Echinodermata class Ophiuroidea, were characterized, as part of attempts to understand the evolutionary development of these polysaccharides. A population of chondroitin sulfate/dermatan sulfate (CS/DS) chains with a high overall degree of sulfation and hexuronate epimerization was the major GAG found, whereas heparan sulfate (HS) was below detection level. Enzymatic digestion with different chondroitin lyases revealed exceptionally high proportions of di- and trisulfated CS/DS disaccharides. The latter unit appears much more abundant in one of four individual species of brittlestars, Amphiura filiformis, than reported earlier in other marine invertebrates. The brittlestar CS/DS was further shown to bind to growth factors such as fibroblast growth factor 2 and to promote FGF-stimulated cell signaling in GAG-deficient cell lines in a manner similar to that of heparin. These findings point to a potential biological role for the highly sulfated invertebrate GAGs, similar to those ascribed to HS in vertebrates.
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Directory of Open Access Journals (Sweden)
Beatriz Mothes
2006-09-01
Full Text Available As amostras foram coletadas com draga retangular ao largo da costa (04º13'00" -02º34'02" N, 47º54'05" -50º50'07" W, pela Comissão Pesca Norte I, em 1968, através da Diretoria de Hidrografia e Navegação da Marinha do Brasil com o N./Oc. " Almirante Saldanha" em profundidades que variaram de 56 a 95 m. Oito espécies são aqui registradas, entre as quais Niphates alba Van Soest, 1980, Placospongia melobesioides Gray, 1867 e Terpios belindae Rützler & Smith, 1993 são identificadas pela primeira vez para a costa brasileira. As demais espécies, Aplysina fulva (Pallas, 1766, Ircinia strobilina (Lamarck, 1816, Niphates erecta (Duchassaing & Michelotti, 1864, Neopetrosia proxima (Duchassaing & Michelotti, 1864 e Plakinastrella onkodes Uliczka, 1929 são conhecidas pela primeira vez para a área estudada. Todas as espécies identificadas são também registradas para o Caribe. Os espécimes encontram-se depositados na Coleção de Porifera do Museu de Ciências Naturais, Fundação Zoobotânica do Rio Grande do Sul, Brasil.The collections were dredged off the coast (04º13'00" -02º34'02" N, 47º54'05" -50º50'07" W. They were collected between 56 to 95 depths, during an oceanographic expedition, Diretoria de Hidrografia e Navegação da Marinha do Brasil, by R/V " Almirante Saldanha" in 1968. Eight species are here registered, among which Niphates alba Van Soest, 1980, Placospongia melobesioides Gray, 1867 and Terpios belindae Rützler & Smith, 1993 represent new registers for Brazil. The other species: Aplysina fulva (Pallas, 1766, Ircinia strobilina (Lamarck, 1816, Niphates erecta Duchassaing & Michelotti, 1864, Neopetrosia proxima (Duchassaing & Michelotti, 1864 and Plakinastrella onkodes Uliczka, 1929 represent new records to the studied area. All registered species are also known from Caribbean. Specimens are deposited in the Porifera Collection of the Museu de Ciências Naturais, Fundação Zoobotânica do Rio Grande do Sul, Brazil.
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Seasonal grazing and food preference of herbivores in a Posidonia oceanica meadow
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Andrea Peirano
2001-12-01
Full Text Available Seasonal grazing of the fish Sarpa salpa (L., the urchin Paracentrotus lividus Lamarck and the isopods Idotea spp. was compared with the C/N ratio of adult and intermediate leaves and epiphytes of Posidonia oceanica (L. Delile, collected at three different depths. Despite seasonal differences in grazing, herbivores showed preferences throughout the year for adult leaves with more epiphyte and higher N contents. The maximum grazing on adult and intermediate leaves was observed in September and in June for fish and in March for urchins, whereas it was irregular for isopods. Grazing by the three herbivores was not related to their preference for leaves or epiphytes, notwithstanding the seasonal differences in their C and N contents. We concluded that herbivores show no preference for food type throughout the year and that seasonal consumption of P. oceanica is related mainly to herbivore behaviour.
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Maria das Graças Avila Guimarães
2015-07-01
Full Text Available Os conceitos evolucionistas começaram a se fundamentar a partir de Descartes, Buffon, Lamarck e Darwin e ao mesmo tempo despertaram as contradições das doutrinas criacionistas. A credibilidade do evolucionismo por faixa etária dos alunos de graduação da Universidade Severino Sombra (USS, nas diferentes áreas do saber foi o objeto deste trabalho. A população discente se concentrou na faixa etária entre 20 a 24 anos em que predomina o acreditar em ideias evolucionistas, não se podendo avaliar se estes posicionamentos independem da divulgação ou do ensino do criacionismo introduzido há algum tempo nas escolas públicas de alguns estados brasileiros. Pode-se inferir, a partir deste estudo, um grande desconhecimento sobre a teoria científica evolucionista entre os discentes dos cursos superiores pesquisados na USS.
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HENRY H. CHEEK AND TRANSFORMISM: NEW LIGHT ON CHARLES DARWIN'S EDINBURGH BACKGROUND.
Jenkins, Bill
2015-06-20
Evidence for the transformist ideas espoused by Henry H. Cheek (1807-33), a contemporary of Charles Darwin's at the University of Edinburgh, sheds new light on the intellectual environment of Edinburgh in the late 1820s and early 1830s. Cheek was the author of several papers dealing with the transmutation of species influenced by the theories of Etienne Geoffroy Saint-Hilaire (1772-1844), Jean-Baptiste Lamarck (1744-1829) and the Comte de Buffon (1707-88). Some of these were read to student societies, others appeared in the Edinburgh Journal of Natural and Geographical Science, which Cheek edited between 1829 and 1831. His writings give us a valuable window onto some of the transformist theories that were circulating among Darwin's fellow medical students in the late 1820s, to which Darwin would have been exposed during his time in Edinburgh, and for which little other concrete evidence survives.
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Directory of Open Access Journals (Sweden)
FREDERICK H C HOTCHKISS
2000-12-01
Full Text Available Very rarely a ray of a sea star is unusually wide and has two parallel ambulacral grooves that extend to a single tip. Such a ray has two terminal plates that are coalesced laterally. This abnormality is inferred to develop as a rare result of regeneration because it is recorded from a species with obligate asexual reproduction (fission and regeneration of halves; no gametes. This conclusion is supported also by an example where the abnormality affects only the distal third of a rayMuy raramente un rayo de estrella de mar es desproporcionadamente ancho y tiene dos surcos ambulacrales paralelos que se extienden hasta su único extremo. Dicho rayo tiene dos placas terminales que coalecen lateralmente. Se ha inferido que esta anormalidad se desarrolla como un resultado raro de regeneración, porque se describe de una especie con reproducción asexual obligada (fisión y regeneración de mitades; no gametos. Además, esta conclusión se sostiene por un ejemplo de anormalidad que afecta sólo el tercio distal de un rayo
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Edilson Matos
2000-09-01
Full Text Available The fine structure of the spermatozoon in the Mellita quinquiesperforata Leske, 1778 was studied. Collected from the Amazon region, were described by light and transmission electron microscopy. The spermatozoon consisted of a acrosome complex, nucleus, four to six mitochondria, two centrioles and flagellum. The acrosome was composed of a acrosome complex, the acrosomal vesicle and the subacrosomal space. The nucleus are composed by dense material. The middle piece contains 4-6 mitochondria which are arranged around the centrioles, the 9p+0, whose axoneme has the classic 9p+2 microtubular construction.
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Tominaga, Hideyuki; Hirose, Mamiko; Igarashi, Hikaru; Kiyomoto, Masato; Komatsu, Miéko
2017-08-01
We describe a new species of sexually dimorphic brittle star, Ophiodaphne spinosa, from Japan associated with the irregular sea urchin, Clypeaster japonicus based on its external morphology, and phylogenetic analyses of mitochondrial COI (cytochrome c oxidase subunit I). Females of this new species of Ophiodaphne are characterized mainly by the presence of wavy grooves on the surface of the radial shields, needle-like thorns on the oral skeletal jaw structures, and a low length-to-width ratio of the jaw angle in comparison with those of type specimens of its Ophiodaphne congeners: O. scripta, O. materna, and O. formata. A tabular key to the species characteristics of Ophiodaphne is provided. Phylogenetic analyses indicate that the new species of Ophiodaphne, O. scripta, and O. formata are monophyletic. Our results indicate that the Japanese Ophiodaphne include both the new species and O. scripta, and that there are four Ophiodaphne species of sexually dimorphic brittle stars with androphorous habit.
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Joshua Militar Regalado
2010-12-01
Full Text Available The sea urchin Tripneustes gratilla is a major grazer found in seagrass beds of southern Guimaras, Philippines. Monthly length-frequency data from January 2008 to June 2009 were used to estimate the growth, recruitment pattern and mortality rate with the use of FiSAT II. The estimated values for the Von Bertalanffy growth parameters L(n/k(asymptotic length and K (growth coefficient were 114.2 mm and 1.08 respectively. Monthly densities ranged from 0.06 to 0.58 per m² with a mean value of 0.26 per m². Monthly biomass ranged from 4.1 to 49.5 grams per m² with a mean value of 21.15 grams per m². T. gratilla density and biomass were observed to be highest during the month of November 2008. The recruitment pattern showed a major broad peak and a minor peak separated by four months. Total mortality (Z from the length-converted catch curve was computed to be 4.74 per year.
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Timothy D. O'Hara
2018-03-01
Full Text Available A new classification of Ophiuroidea, considering family rank and above, is presented. The new family and superfamily taxa in O’Hara et al. (2017 were proposed to ensure a better readability of the new phylogeny but are unavailable under the provisions of the ICZN. Here, the morphological diagnoses to all 33 families and five superfamilies are provided. Ten new families, Ophiosphalmidae fam. nov., Ophiomusaidae fam. nov., Ophiocamacidae fam. nov., Ophiopteridae fam. nov., Clarkcomidae fam. nov., Ophiopezidae fam. nov., Ophiernidae fam. nov., Amphilimnidae fam. nov., Ophiothamnidae fam. nov. and Ophiopholidae fam. nov., are described. The family Ophiobyrsidae Matsumoto, 1915, not yet discovered in the previous publication, is added, based on new molecular data. A new phylogenetic reconstruction is presented. Definitions of difficult-to-apply morphological characters are given.
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A. Chattopadhyay, S. Adhikari, S. P. Adhikary, S. Ayyappan
2006-04-01
Full Text Available In this investigation, the efficacy of the herbicide butachlor, (N-butoxymethyl-2 chloro-21, 61 diethyl acetanilide was tested against few common submerged macrophytes namely Hydrilla (Hydrilla verticillata (L. Royale, Najas (Najas minor All., Nechamandra (Nechamandra alternifolia (Roxb. Thwaites and Ottelia (Ottelia alismoides (L. Pers. of freshwater fish ponds. Almost complete decay of Hydrilla, Nechamandra and Ottelia was achieved at 7.5 L of active ingredient/ha/m butachlor within 15 days while the herbicide showed no negative effect on Najas. However at the same concentration of butachlor, total mortality of zooplankton and water fern Azolla (Azolla caroliniana Lamarck occurred within seven days. In case of few freshwater fish species like Rohu (Labeo rohita, Channa (Channa punctatus, Anabas (Anabas testitudineus and Heteropneustes (Heteropneustes fossilis, total mortality occurred upto 90 days after application of the same dose of butachlor but fish survived beyond 120 days of herbicide application indicating degradation of the herbicides.
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Nonequilibrium population dynamics of phenotype conversion of cancer cells.
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Joseph Xu Zhou
Full Text Available Tumorigenesis is a dynamic biological process that involves distinct cancer cell subpopulations proliferating at different rates and interconverting between them. In this paper we proposed a mathematical framework of population dynamics that considers both distinctive growth rates and intercellular transitions between cancer cell populations. Our mathematical framework showed that both growth and transition influence the ratio of cancer cell subpopulations but the latter is more significant. We derived the condition that different cancer cell types can maintain distinctive subpopulations and we also explain why there always exists a stable fixed ratio after cell sorting based on putative surface markers. The cell fraction ratio can be shifted by changing either the growth rates of the subpopulations (Darwinism selection or by environment-instructed transitions (Lamarckism induction. This insight can help us to understand the dynamics of the heterogeneity of cancer cells and lead us to new strategies to overcome cancer drug resistance.
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Shengzhang Dong
2012-04-01
Full Text Available The wild rice, Zizania latifolia Turcz, used to be one of the important aquatic vegetables cultivated in China. Recently, the golden apple snail - GAS (Pomacea canaliculata (Lamarck was found to be a major invasive pest attacking Z. latifolia. To control efficiently GAS, predation by the Chinese soft-shelled turtles (Pelodiscus sinensis on GAS was evaluated in laboratory and field trials. P. sinensis had a strong predatory capacity and selectivity for GAS both in laboratory and field conditions. All the sizes of P. sinensis prefer to capture smaller snails. The optimum number of P. sinensis released in Z. latifolia field was dependent on the density of over-wintered GAS, and varied between 30 and 50 turtles per 666.7 m². The number of GAS declined in the fields with turtles as compared to turtle-free field. A pattern of releasing P. sinensis in Z. latifolia fields was developed and widely adopted by farmers because of much more benefit besides biologically controlling GAS.
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Phrenology, heredity and progress in George Combe's Constitution of Man.
Jenkins, Bill
2015-09-01
The Constitution of Man by George Combe (1828) was probably the most influential phrenological work of the nineteenth century. It not only offered an exposition of the phrenological theory of the mind, but also presented Combe's vision of universal human progress through the inheritance of acquired mental attributes. In the decades before the publication of Darwin's Origin of Species, the Constitution was probably the single most important vehicle for the dissemination of naturalistic progressivism in the English-speaking world. Although there is a significant literature on the social and cultural context of phrenology, the role of heredity in Combe's thought has been less thoroughly explored, although both John van Wyhe and Victor L. Hilts have linked Combe's views on heredity with the transformist theories of Jean-Baptiste Lamarck. In this paper I examine the origin, nature and significance of his ideas and argue that Combe's hereditarianism was not directly related to Lamarckian transformism but formed part of a wider discourse on heredity in the early nineteenth century.
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Popper y Darwin: Evolucionismo Bio-Cosmológico y Epistemología Evolucionista
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Juan Arana
2015-02-01
Full Text Available La capacidad de generalizar es uno de los rasgos más característicos de Popper como filósofo. Propone un lamarckismo sin Lamarck, un vitalismo sin principios vitales ni entelequias, y un animismo sin alma. En el fondo, es lo mismo que hizo Darwin con la teleología gracias a la selección natural: patrocinar un finalismo sin fines. La especulación es atrevida pero en modo alguno rechazable. El problema de Popper es que a veces no sabe contenerse y se implica demasiado en el debate científico de primera línea. Le ocurrió algo parecido con las discusiones que siguieron al desarrollo de la mecánica cuántica: en lugar de moverse con cautela en el terreno de la reflexión metateórica, tuvo que proponer un «experimento mental» para mediar en la controversia Einstein-Bohr.
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T. K. Misra
1993-09-01
Full Text Available The life-cycle parameters of the snail Lymnaea (Radix luteola and the factors influencing the same have been studied under laboratory conditions. Ins each month, from July 1990 to June 1991, a batch of 100 zero-day old individual were considered for studies. The snails of April batch survived for 19.42 days while those in December batch survived for 87.45 days. The May batch individual though survived for 65.67 days gained maximum shell size (15.84 mm in length and body weight (419.87 mg. All individuals of April batch died prior to attainment of sexual maturity. In the remaining 11 batches the snails became sexually mature between 32 and 53 days. At this stage, they were with varying shell lengths, 9.3 mm to 13,11 mm in respect to batches. The reproduction period varied from 1-67 days. An individual laid, on an average, 0,25 (March batch to 443.67 (May batch eggs in its life-span. A batch of such snails would leave 24312, 22520, 720268, 80408, 76067, 418165, 214, 9202, 0, 0, 2459386 and 127894 individuals at the end of 352nd day. Since the environmental conditions were almost similar the 'dynamic' of population dynamics seems to be involved with the 'strain' of the snail individuals of the batches concerned.
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Role and convergent evolution of competing RNA secondary structures in mutually exclusive splicing.
Yue, Yuan; Hou, Shouqing; Wang, Xiu; Zhan, Leilei; Cao, Guozheng; Li, Guoli; Shi, Yang; Zhang, Peng; Hong, Weiling; Lin, Hao; Liu, Baoping; Shi, Feng; Yang, Yun; Jin, Yongfeng
2017-10-03
Exon or cassette duplication is an important means of expanding protein and functional diversity through mutually exclusive splicing. However, the mechanistic basis of this process in non-arthropod species remains poorly understood. Here, we demonstrate that MRP1 genes underwent tandem exon duplication in Nematoda, Platyhelminthes, Annelida, Mollusca, Arthropoda, Echinodermata, and early-diverging Chordata but not in late-diverging vertebrates. Interestingly, these events were of independent origin in different phyla, suggesting convergent evolution of alternative splicing. Furthermore, we showed that multiple sets of clade-conserved RNA pairings evolved to guide species-specific mutually exclusive splicing in Arthropoda. Importantly, we also identified a similar structural code in MRP exon clusters of the annelid, Capitella teleta, and chordate, Branchiostoma belcheri, suggesting an evolutionarily conserved competing pairing-guided mechanism in bilaterians. Taken together, these data reveal the molecular determinants and RNA pairing-guided evolution of species-specific mutually exclusive splicing spanning more than 600 million years of bilaterian evolution. These findings have a significant impact on our understanding of the evolution of and mechanism underpinning isoform diversity and complex gene structure.
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The Sponge Zygomycale parishii(Bowerbank) and its Endobiotic Fauna
Duarte, Luiz; Nalesso, Rosebel
1996-02-01
The endobiotic fauna of the sponge Zygomycale parishii(Bowerbank) was studied for 2·5 years at two sites, Ubatuba and São Sebastião, on the northern coast of the State of São Paulo, Brazil. Ninety-two macrofaunal species (over 1 mm long) were identified among which Cnidaria, Turbellaria, Nemertinea, Sipuncula, Polychaeta, Mollusca, Crustacea, Pycnogonida, Echinodermata, Ascidiacea and Pisces were represented. The results obtained on the number of species (species richness), the abundances of different species and faunal composition were related to the physico-biotic characteristics of the study sites. The influence of sample volume and other methodological artifacts on sample characteristics were also examined. The ophiuroid Ophiactis savignyi(Müller & Troschell) was the dominant endobiotic species, comprising 64% of all individuals collected. The São Sebastião endobiotic fauna was more diversified than the Ubatuba endobiotic fauna, possibly due to higher larval recruitment, and to the closeness of Z. parishiito the sea-floor providing a greater possibility for inhabitants of this microhabitat to find and to live inside the sponge.
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Medicinal benefits of marine invertebrates: sources for discovering natural drug candidates.
De Zoysa, Mahanama
2012-01-01
Marine invertebrates are one of the major groups of organisms, which could be diversified under the major taxonomic groups of Porifera, Cnidaria, Mollusca, Arthropoda, Echinodermata, and many other minor phyla. To date, range of medicinal benefits and a significant number of marine natural products (MNPs) have been discovered from marine invertebrates. Seafood diet from edible marine invertebrates such as mollusks and crustaceans has been linked with various medicinal benefits to improve human health. Among marine invertebrates, spongers from phylum Porifera is the most dominant group responsible for discovering large number of MNPs, which have been used as template to develop therapeutic drugs. MNPs isolated from invertebrates have shown wide range of therapeutic properties including antimicrobial, antioxidant, antihypertensive, anticoagulant, anticancer, anti-inflammatory, wound healing and immune modulator, and other medicinal effects. Therefore, marine invertebrates are rich sources of chemical diversity and health benefits for developing drug candidates, cosmetics, nutritional supplements, and molecular probes that can be supported to increase the healthy life span of human. Copyright © 2012 Elsevier Inc. All rights reserved.
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Barboza, C. A. M.
2010-01-01
Full Text Available The Gorgonocephalidae includes 38 genera, five of them reported for Brazilian waters. Gorgonocephalus chilensishas a wide distribution throughout Antartica and Subantartican regions and its northern limit was restricted to the coast ofUruguay. This work aims to report the first occurrence of the Gorgonocephalus genus for the Brazilian continental marginand extend the northern limit of distribution of G. chilensis to the coast of Santa Catarina. Tolerance to a large temperatureand bathimetric range are crucial to understand the distributions patterns of ophiuroids from the polar circle that alsooccur at southern South America.
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Wang, Yan; Liu, Huijie; Sun, Zhongsheng
2017-11-01
Organisms can change their physiological/behavioural traits to adapt and survive in changed environments. However, whether these acquired traits can be inherited across generations through non-genetic alterations has been a topic of debate for over a century. Emerging evidence indicates that both ancestral and parental experiences, including nutrition, environmental toxins, nurturing behaviour, and social stress, can have powerful effects on the physiological, metabolic and cellular functions in an organism. In certain circumstances, these effects can be transmitted across several generations through epigenetic (i.e. non-DNA sequence-based rather than mutational) modifications. In this review, we summarize recent evidence on epigenetic inheritance from parental environment-induced developmental and physiological alterations in nematodes, fruit flies, zebrafish, rodents, and humans. The epigenetic modifications demonstrated to be both susceptible to modulation by environmental cues and heritable, including DNA methylation, histone modification, and small non-coding RNAs, are also summarized. We particularly focus on evidence that parental environment-induced epigenetic alterations are transmitted through both the maternal and paternal germlines and exert sex-specific effects. The thought-provoking data presented here raise fundamental questions about the mechanisms responsible for these phenomena. In particular, the means that define the specificity of the response to parental experience in the gamete epigenome and that direct the establishment of the specific epigenetic change in the developing embryos, as well as in specific tissues in the descendants, remain obscure and require elucidation. More precise epigenetic assessment at both the genome-wide level and single-cell resolution as well as strategies for breeding at relatively sensitive periods of development and manipulation aimed at specific epigenetic modification are imperative for identifying parental environment-induced epigenetic marks across generations. Considering their diverse epigenetic architectures, the conservation and prevalence of the mechanisms underlying epigenetic inheritance in non-mammals require further investigation in mammals. Interpretation of the consequences arising from epigenetic inheritance on organisms and a better understanding of the underlying mechanisms will provide insight into how gene-environment interactions shape developmental processes and physiological functions, which in turn may have wide-ranging implications for human health, and understanding biological adaptation and evolution. © 2017 The Authors. Biological Reviews published by John Wiley & Sons Ltd on behalf of Cambridge Philosophical Society.
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Weissert, Helmut
2013-04-01
With the beginning of the fossil fuel age in the 19th century mankind has become an important geological agent on a global scale. For the first time in human history action of man has an impact on global biogeochemical cycles. Increasing CO2 concentrations will result in a perturbation of global carbon cycling coupled with climate change. Investigations of past changes in carbon cycling and in climate will improve our predictions of future climate. Increasing atmospheric CO2 concentrations will drive climate into a mode of operation, which may resemble climate conditions in the deep geological past. Pliocene climate will give insight into 400ppm world with higher global sea level than today. Doubling of pre-industrial atmospheric CO2 levels will shift the climate system into a state resembling greenhouse climate in the Early Cenozoic or even in the Cretaceous. Carbon isotope geochemistry serves as tool for tracing the pathway of the carbon cycle through geological time. Globally registered negative C-isotope anomalies in the C-isotope record are interpreted as signatures of rapid addition (103 to a few 104 years) of CO2 to the ocean-atmosphere system. Positive C-isotope excursions following negative spikes record the slow post-perturbation recovery of the biosphere at time scales of 105 to 106 years. Duration of C-cycle perturbations in earth history cannot be directly compared with rapid perturbation characterizing the Anthropocene. However, the investigation of greenhouse pulses in the geological past provides insight into different climate states, it allows to identify tipping points in past climate systems and it offers the opportunity to learn about response reactions of the biosphere to rapid changes in global carbon cycling. Sudden injection of massive amounts of carbon dioxide into the atmosphere is recorded in C-isotope record of the Early Cretaceous. The Aptian carbon cycle perturbation triggered changes in temperature and in global hydrological cycling. Changes in physical and chemical oceanography are reflected in widespread black shale deposition ("Oceanic Anoxic Event 1a"), in carbonate platform drowning and in biocalcification crises. "Days of future passed" (Moody Blues, 1967) reminds us that the past provides essential information needed for decisions to be made in the interest of mankind's future.
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Limestones: the love of my life - sun, sea and cycles (Jean Baptiste Lamarck Medal Lecture)
Tucker, M. E.
2009-04-01
In studies of sedimentary rocks we are striving to understand the short and long-term controls on deposition that lead to the variety of facies we see in the geological record. With the development and application of sequence stratigraphy has come the realisation that in most cases the stratigraphic record is not random, but there are patterns and trends in the nature (composition, facies, diagenesis) and thickness of sedimentary units. In addition, sedimentary cycles are widely, if not ubiquitously, developed through stratigraphic successions, and do themselves vary in thickness and facies through a formation and through time. In many cases, orbital forcing is clearly a major control, in addition to longer term tectonic and tectono-eustatic processes. Understanding the major controls on the stratigraphic record and the processes involved in deposition enables us to develop a degree of prediction for the occurrence of particular facies and rock-types. This is especially significant in terms of hydrocarbon potential in frontier basins, notably in the search for source and reservoir rocks. In the case of carbonate and carbonate-evaporite successions, recent work is showing that even at the higher-frequency scale of individual beds and bed-sets, there are regular patterns and changes in thickness. These show that controls on deposition are not random but well organised. Studies of Carboniferous shelf/mid-ramp bioclastic limestones and Jurassic shallow-marine oolites from England reveal systematic variations in bed thickness, as well as oxygen isotopes, Sr and org C values. Permian lower slope carbonates from NE England show thinning-thickening-upward patterns in turbidite bed thickness on several orders of scale. Turbidity current frequency of 1 per ~200 years can be deduced from thicknesses of interbedded laminated facies, which provide the timescale. Beds in ancient shelf and slope carbonates of many geological periods are on a millennial-scale and their features and patterns clearly indicate that millennial-scale changes in climate, most likely driven by fluctuations in solar output, analogous to the D-O cycles of the Quaternary, were responsible, and that these were then modulated by orbital forcing. Solar forcing rules in carbonates, even at the highest frequency.
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Premoli Silva, Isabella
2014-05-01
The mid of the last century was a time of flourishing studies concerning the importance of planktonic foraminifera in precisely dating and correlating sedimentary successions after the publication of the first biostratigraphic schemes provided by the Suisse Group (i.e. Kugler, Bolli, Broennimann) from the Caribbean region and former Southern USSR (Subbotina). Soon after Bolli's Trinidad scheme was widespread, planktonic foraminiferal distribution from Upper Cretaceous to Miocene was investigated intensively for dating the Neogene stratotypes, whose identifications were mainly based on poorly age-diagnostic, facies-controlled macrofossils, and for calibrating Paleogene larger foraminiferal distributions. Since these early works planktonic foraminiferal biostratigraphy was continously ameliorated, extended in time from Early Cretaceous to Recent by several authors and from different settings and domains, reaching progressively the current higher resolution, now calibrated to calcareous nannofossil distributions. To be mentioned, the detailed biostratigraphic studies on the Gubbio section (central Italy) provided (1) the first carefull documentation of the mass extinction of Cretaceous planktonic foraminifera, the presence of tiny Cretaceous survivors, and the rapid recovery of Danian assemblages, and (2) the first calibration of the Upper Cretaceous to Eocene reversal polarity scale in which the K/Pg boundary was demonstrated to fall within the magnetic reversal C29r. A major step forward was the recovery, since 1968, of several thousand of cores from over 1000 holes drilled in all oceans by the DSDP, ODP and IODP projects. The recovery of deep-sea sediments from all latitudes opened a new research field, the paleoceanography. Based on the large knowledge acquired on modern organisms in the '60s, for the Paleogene and Cretaceous reconstructions we started from the assumption that these extinct organisms lived in the water column like their modern counterpart and were controlled by similar environmental factors (temperature, nutrient supply, current system, etc.), then the fluctuations in abundance and composition of planktonic foraminiferal assemblages could be interpreted in term of paleobiogeography and paleoceanography. The first studies, rigorously quantitative, have been conducted in the '70s on the Paleogene of the Atlantic Ocean, the interval with the best latitudinal coverage at that time. From the areal distribution and variations in assemblage composition through time we (with A. Boersma) were able to identify first the biogeographic indices, then their paleoclimatic significances, from which we could reconstruct the paleoclimatic and paleoceanographic evolution. The associated isotope analyses (with N. Shackleton) on single species allowed to confirm the species latitudinal connotations as well as their position within the water column (mixed layer vs deep dwelling habitats) and preferences for nutrient supply. In the '90s we (with W.V. Sliter) extended the paleoceanographic reconstructions to the Cretaceous exploring the planktonic foraminiferal evolutionary patterns and latitudinal changes in assemblage composition through time. Like in the Paleogene, it was possibile to identify that the more ornamented keeled forms were very sensitive to temperature, liked warm waters and were more abundant in the tropics, the simpler morphologies were less sensitive, more tolerant and cosmopolitan, while, for instance, whiteinellids proliferated in upwelling regions. In the last decade, taking advantage of the wealth of paleoecological and biogeographical data previously collected, we started a new phase of deep taxonomical and stratigraphical revision of planktonic foraminifera. Increased biostratigraphic resolution from tropics to high latitudes is facilitated by the integration with other fossil group biostratigraphies and magneto-, isotope-stratigraphies.
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Randall, Carly J; Szmant, Alina M
2009-12-01
Elevated seawater temperatures during the late summer have the potential to negatively affect the development and survivorship of the larvae of reef corals that are reproductive during that time of year. Acropora palmata, a major Caribbean hermatype, reproduces annually during August and September. A. palmata populations have severely declined over the past three decades, and recovery will require high recruitment rates. Such recruitment will be limited if larval supply is reduced by elevated temperatures. The effects of elevated temperatures on development, survival, and larval settlement of A. palmata were investigated by culturing newly fertilized eggs at temperatures ranging from 27.5 to 31.5 degrees C. Development was accelerated and the percentage of developmental abnormalities increased at higher temperatures. Embryo mortality peaked during gastrulation, indicating that this complex developmental process is particularly sensitive to elevated temperatures. Larvae cultured at 30 and 31.5 degrees C experienced as much as an 8-fold decrease in survivorship compared to those at 28 degrees C. Additionally, settlement was 62% at 28 degrees C compared to 37% at 31.5 degrees C. These results indicate that embryos and larvae of A. palmata will be negatively affected as sea surface temperatures continue to warm, likely reducing recruitment and the recovery potential of A. palmata on Caribbean reefs.
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Turbil, Cristiano
2017-09-01
In 1884 Samuel Butler published a collection of essays entitled Remarks on George Romanes' Mental Evolution, where he attempted to show how Romanes' idea of mental evolution presented similarities with his theory of unconscious memory. By looking at Romanes' work through Butler's writing, this article will reevaluate some aspects of their works regarding the complex debate about memory, heredity, and instinct. This paper will explore the main differences and similarities between Romanes' science and Butler's writing on science both in terms of their ideas and contents. It will then look into their different professional relationships with Darwin and how this determined the professional and public reception of their theories. © 2017 Wiley Periodicals, Inc.
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LEYLA CÁRDENAS
2008-09-01
Full Text Available The muricid gastropod Concholepas concholepas, known in Chile as 'loco', is an important component of intertidal and shallow subtidal communities, and is one of the main invertebrates targeted by small-scale fishers (divers in Chile. Because of its ecological importance and economical value, numerous studies have been conducted to describe its life history, ecology and to understand population dynamics, fishery and management. However, little effort has been done to address the causal factor (s behind its current geographic distribution and moreover little is known about the past distribution of the different species in the genus. In this paper, first we review the paleobiogeography, historical relationships, taxonomy and geographical distribution of Concholepas species, so to contribute in the reconstruction on the past history of the genus. Second, we discuss the robustness of using shell traits when classifying specimens of the genus Concholepas. Third, we evaluate the taxonomic status of C. concholepas including samples from Peru, the continental coast of Chile and Juan Fernández Archipelago, using a molecular approach. Four main conclusions are reached: (1 the evolutionary history of the genus Concholepas has been characterized by successive phenotypically different forms where the fossils species appear to be distinguishable states in the same evolving lineage; (2 the historical biogeography of Concholepas was probably the result of a southward direction process of expansions and extinctions, with the ancestral species being located in south-central Peru; (3 C. concholepas corresponds to a single taxonomic unit along its continental geographical range of distribution; (4 the mtDNA variation present in C. concholepas does not support the existence of the subspecies C. concholepas fernandizianus in the Juan Fernández Archipelago. We suggest that these results should be considered in future ecological, fishery, management and conservation studies on C. concholepas along the Peruvian and Chilean coast and in the Juan Fernández Archipelago.El gastrópodo muricido Concholepas concholepas, conocido en Chile como 'loco', es un importante componente de comunidades marinas intermareales y submareales y es una de las principales especies de invertebrados en la pesquería artesanal chilena. Debido a su importancia y valor económico, se han realizado numerosos estudios para describir su historia de vida, ecología y entender las dinámicas poblacionales, pesquería y manejo. Sin embargo, menores esfuerzos han sido realizados para entender los factores causales detrás de su actual distribución geográfica y más aún poco es conocido acerca de la pasada distribución de las diferentes especies del género. En este trabajo, nosotros primero revisamos la paleobiogeografía, relaciones históricas y taxonomía, de las especies del género Concholepas para contribuir en la reconstrucción de la historia pasada del género. Segundo, discutimos la robustez de usar caracteres morfológicos en la taxonomía del género. Tercero, usando una aproximación molecular evaluamos el estatus taxonómico de C. concholepas incluyendo muestras desde Perú, la costa continental de Chile y del archipiélago de Juan Fernández. Se obtuvieron cuatro conclusiones principales: (1 la historia evolutiva del género Concholepas ha sido caracterizada por sucesivas formas fenotípicamente diferentes, donde las especies fósiles parecen ser estados morfológicos distinguibles de un único linaje evolutivo; (2 la biogeografía histórica de Concholepas parece ser resultado de un proceso continuo de expansión y extinción con dirección sur, con las especies ancestrales localizadas en el centro-sur de Perú; (3 C. concholepas corresponde a una sola unidad taxonómica a lo lago de su rango de distribución continental; (4 la variación en el ADNmt detectada en C. concholepas no apoya la existencia de la subespecie C. concholepas fernandizianus en el Archipiélago de Juan Fernández. Sugerimos que estos resultados deberán ser considerados en futuros estudios de ecología, pesquería, conservación y manejo en C. concholepas a lo largo de la costa chileno-peruana y en el archipiélago de Juan Fernández.
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Composite Agency: Semiotics of Modularity and Guiding Interactions.
Sharov, Alexei A
2017-07-01
Principles of constructivism are used here to explore how organisms develop tools, subagents, scaffolds, signs, and adaptations. Here I discuss reasons why organisms have composite nature and include diverse subagents that interact in partially cooperating and partially conflicting ways. Such modularity is necessary for efficient and robust functionality, including mutual construction and adaptability at various time scales. Subagents interact via material and semiotic relations, some of which force or prescribe actions of partners. Other interactions, which I call "guiding", do not have immediate effects and do not disrupt the evolution and learning capacity of partner agents. However, they modify the extent of learning and evolutionary possibilities of partners via establishment of scaffolds and constraints. As a result, subagents construct reciprocal scaffolding for each other to rebalance their communal evolution and learning. As an example, I discuss guiding interactions between the body and mind of animals, where the pain system adjusts mind-based learning to the physical and physiological constraints of the body. Reciprocal effects of mind and behaviors on the development and evolution of the body includes the effects of Lamarck and Baldwin.
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Long-term maintenance of the sea urchin Paracentrotus lividus in culture
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Paola Cirino
2017-08-01
Full Text Available The common sea urchin Paracentrotus lividus (Lamarck, 1816 is an important commercial species in the Mediterranean Sea for the consumption of its gonads (roe. This species has also long been used as an animal model in developmental biology and as an indicator in the assessment of environmental quality. In recent decades, the exploitation of this marine resource has become increasingly intensive, causing the depletion of wild stocks. The ripple effect observed in the laboratory use of this species has been the growing difficulty in finding valiant mature animals in the wild. We focused on the long-term maintenance of wild P. lividus and on the essential question of diet to maintain the animals and improve gonad development. The use of practical ration blocks which are nutrient-rich and show stability, easy storage and handling, resulted reduction in labor requirement and time for feeding streamlining the feeding practice. A significantly higher gonad production and a prolonged period of reproduction were obtained compared to wild caught individuals over the same period of time.
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Sergio Cházaro-Olvera
2018-03-01
Full Text Available ABSTRACT The present study provides information on the morphology of stomatopod larvae found in two different reef systems which are also considered national parks: the Sistema Arrecifal Veracruzano (SAVNP and Arrecife Puerto Morelos (APMNP. Zooplankton samples were collected at 26 stations of the SAVNP and four stations of the APMNP. Stomatopod larvae were identified and classified by their larval stage. We found representatives of three stomatopod superfamilies: the superfamily Gonodactyloidea Giesbrecht, 1910 was represented by Neogonodactylus oerstedii (Hansen, 1895, Neogonodactylus wennerae Manning and Heard, 1997, and Pseudosquillidae genus and species indeterminate; the superfamily Lysiosquilloidea Giesbrecht, 1910 was represented by Lysiosquilloidea genus and species indeterminate, Lysiosquilla sp., Lysiosquilla scabricauda (Lamarck, 1818 and Nannosquilla adkisoni Camp and Manning, 1982; the superfamily Squilloidea was represented by larvae of Alima neptuni (Linnaeus, 1768, Squilla spp., and Squilla empusa Say, 1818. We were able to identify and describe four stages of larval development for representatives of these superfamilies. This is the first study describing several stages of larval development of different species of the stomatopods from the Gulf of Mexico and Caribbean Sea.
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Use/disuse paradigms are ubiquitous concepts in characterizing the process of inheritance.
Veigl, Sophie Juliane
2017-12-02
In recent years, a Lamarckian theme has found its way back into academic discourse on evolution and inheritance. Especially the emerging field of transgenerational small RNAs has provided at least a proof of concept for the inheritance of acquired traits. Yet it remains unclear whether the Lamarckian concept of inheritance will in fact have its rennaisance or whether it will remain the rallying cry for the outlaws, heretics and enfants terribles of molecular biology. As unclear as the future of Lamarckian theory is its content and reference. Since the formulation of the Philosophie Zoologique, Lamarckian thought has been de- and reconfiguring in and out of the scientific literature and become an umbrella-term for all kinds of unconventional modes of inheritance. This essay will argue that heritable small RNAs might in fact provide a case of genuine Lamarckian inheritance. Moreover, it will be claimed that not only the very broad concept of "inheritance of acquired traits" applies, but also that Lamarck's mechanistic insight into a use/disuse relation might help to explain a specific mode of transgenerational inheritance.
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Taekjun Lee
2012-07-01
Full Text Available Echinoids were collected at depths of 5-10 m in Munseom, Jeju Island by SCUBA diving on November 23, 2008 and September 15, 2009. Two specimens were identified as Echinometra mathaei (Blainville, 1825 based on morphological characteristics and molecular analyses of mitochondrial cytochrome c oxidase subunit I partial sequences. Echinometra mathaei collected from Korea was redescribed with photographs and was compared with other species from GenBank based on molecular data. Phylogenetic analyses showed that no significant differences were between base sequences of E. mathaei from Korea and that from GenBank. To date, 13 echinoids including this species have been reported from Jeju Island, and 32 echinoids have been recorded in Korea.
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M. Rebeca Granja-Fernández
2011-12-01
Full Text Available Se presentan nuevos registros de ofiuroideos para localidades de Zihuatanejo, Guerrero y de Puerto Escondido, Oaxaca en el Pacífico mexicano. Mediante recolectas realizadas en diversos sustratos se obtuvieron 12 especies, de las cuales Ophiocoma alexandri Lyman, 1860 y Ophiothela mirabilis (Verrill, 1867 fueron las más ampliamente distribuidas. Este número de especies, el más alto registrado respecto a trabajos previos, se atribuye a la mayor amplitud espacial del esfuerzo de muestreo y a la mayor diversidad de sustratos explorados. Se dan a conocer nuevos sustratos habitados por O. mirabilis y Ophioderma panamensis Lütken, 1859. Se presenta el primer registro de asociación de un organismo juvenil de O. alexandri con un hidrozoo del orden Leptothecata en el Pacífico oriental. A pesar del incremento en el número de especies reconocidas para las localidades, se sugiere llevar a cabo una prospección más amplia del Pacífico tropical mexicano y un mayor esfuerzo de muestreo en diversos sustratos con el fin de incrementar el conocimiento de la biodiversidad de ofiuros en la zona.New records of ophiuroids from localities at Zihuatanejo, Guerrero and Puerto Escondido, Oaxaca in the Mexican Pacific are presented. Based on specimens collected on diverse substrata, 12 species were identified; Ophiocoma alexandri Lyman, 1860 and Ophiothela mirabilis (Verrill, 1867 being the most widely distributed. The larger number of recorded species compared to previous studies may result from a spatially broader sampling and a more thorough survey involving a larger variety of substrata. New substrata for O. mirabilis and Ophioderma panamensis Lütken, 1859 are reported. We document, for first time, the relationship between a juvenile of O. alexandri and a hydrozoan of the order Leptothecata in the Eastern Pacific. Although this paper documents a significant increase in the number of recorded species in the study area, we highlight the need for a large scale survey in the tropical Mexican Pacific, along with a more thorough sampling on a larger number of substrata in order to increase our knowledge about ophiuroids in the area.
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Ana Maria Gouveia Monteiro
1983-01-01
Full Text Available Foram examinados 198 exemplares de Gorgonocephalus chilensis das regiões antártica e subantartica, tendo-se em vista a variação de caracteres morfológicos externos. Foi constatada uma grande variação nas características morfológicas externas, que parece independer de localização geográfica.A revision is presented on the variability of the ornamentation and other extermal morphological aspects of Gorgonocephalus chilensis. The samples were obtained along the period of 1962 to 1972 by the R/V "Hero" and "Eltanin" (USARP and by the R/V "Almirante Saldanha" from the Brazilian Navy.
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Mitu, Shahida Akter; Bose, Utpal; Suwansa-Ard, Saowaros; Turner, Luke H; Zhao, Min; Elizur, Abigail; Ogbourne, Steven M; Shaw, Paul Nicholas; Cummins, Scott F
2017-11-07
The sea cucumber (phylum Echinodermata) body wall is the first line of defense and is well known for its production of secondary metabolites; including vitamins and triterpenoid glycoside saponins that have important ecological functions and potential benefits to human health. The genes involved in the various biosynthetic pathways are unknown. To gain insight into these pathways in an echinoderm, we performed a comparative transcriptome analysis and functional annotation of the body wall and the radial nerve of the sea cucumber Holothuria scabra ; to define genes associated with body wall metabolic functioning and secondary metabolite biosynthesis. We show that genes related to signal transduction mechanisms were more highly represented in the H. scabra body wall, including genes encoding enzymes involved in energy production. Eight of the core triterpenoid biosynthesis enzymes were found, however, the identity of the saponin specific biosynthetic pathway enzymes remains unknown. We confirm the body wall release of at least three different triterpenoid saponins using solid phase extraction followed by ultra-high-pressure liquid chromatography-quadrupole time of flight-mass spectrometry. The resource we have established will help to guide future research to explore secondary metabolite biosynthesis in the sea cucumber.
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Shahida Akter Mitu
2017-11-01
Full Text Available The sea cucumber (phylum Echinodermata body wall is the first line of defense and is well known for its production of secondary metabolites; including vitamins and triterpenoid glycoside saponins that have important ecological functions and potential benefits to human health. The genes involved in the various biosynthetic pathways are unknown. To gain insight into these pathways in an echinoderm, we performed a comparative transcriptome analysis and functional annotation of the body wall and the radial nerve of the sea cucumber Holothuria scabra; to define genes associated with body wall metabolic functioning and secondary metabolite biosynthesis. We show that genes related to signal transduction mechanisms were more highly represented in the H. scabra body wall, including genes encoding enzymes involved in energy production. Eight of the core triterpenoid biosynthesis enzymes were found, however, the identity of the saponin specific biosynthetic pathway enzymes remains unknown. We confirm the body wall release of at least three different triterpenoid saponins using solid phase extraction followed by ultra-high-pressure liquid chromatography-quadrupole time of flight-mass spectrometry. The resource we have established will help to guide future research to explore secondary metabolite biosynthesis in the sea cucumber.
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Feeding habits of Pagellus acarne (Sparidae in the Gulf of Tunis, central Mediterranean
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Rafika Fehri-Bedoui
2009-12-01
Full Text Available The feeding habits of the axillary seabream, Pagellus acarne (Risso, 1810, from the Gulf of Tunis were investigated in relation to season, sex and fish size (juveniles TL < 14.5 cm and adults TL ≥ 14.5 cm. A total of 536 specimens (males, females, unsexed and hermaphroditic, ranging between 11.0 and 25.2 cm TL, were collected with trammel nets from June 2005 to July 2006. Their stomach contents were analysed. Of the total number of examined stomachs, 279 stomachs were empty (Vacuity index, VI = 52%. The VI did not reveal significant seasonal differences when all of the specimens were analysed together; however, significant seasonal variations were observed for females. The diet of the axillary seabream was composed of 36 different prey species. The most important prey were Arthropoda, Mollusca and Echinodermata. Both the dietary indices and the Spearman’s coefficient of correlation indicated seasonal variations in the diet. The diet was more diversified in adults than in juveniles. The axillary seabream fed on a wide range of prey items, endofauna and nekton, and can be considered a carnivorous and euryphagous predator.
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Son, Min-Hui; Kim, Jongchul; Shin, Eun-Su; Seo, Sung-Hee; Chang, Yoon-Seok
2015-12-30
The levels and distributional characteristics of hexabromocyclododecane (HBCD) diastereoisomers have been largely reported for various fish and select shellfish. In this study, we reclassified a number and variety of marine invertebrates, including shellfish, to further contribute to the comprehensive understanding of the effects and assessment of human exposure to HBCD. Overall, 30 marine invertebrate species (n=188) were investigated and the following order of ∑2HBCD (α- and γ-HBCD) was observed: fish>chordata>cephalopoda>echinodermata>bivalve>crustacea. The marine invertebrates that were reclassified into nektonic and benthic organisms showed similar concentration of ∑2HBCD. The feeding habits and modes of the marine organisms were considered to compare the degree of bioaccumulation and diastereoisomer-specific distribution of HBCD due to the effects of the environment in and around pollution sources, as well as the organisms' metabolic capacities. To the best of our knowledge, this is the first study to examine the species-specific distribution patterns of HBCD for both fish and marine invertebrates. We expect to significantly expand the understanding of the environmental fate of HBCD for marine organisms. Copyright © 2015 Elsevier B.V. All rights reserved.
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Bracken-Grissom, Heather
2013-12-12
Over 95% of all metazoan (animal) species comprise the invertebrates, but very few genomes from these organisms have been sequenced. We have, therefore, formed a Global Invertebrate Genomics Alliance (GIGA). Our intent is to build a collaborative network of diverse scientists to tackle major challenges (e.g., species selection, sample collection and storage, sequence assembly, annotation, analytical tools) associated with genome/transcriptome sequencing across a large taxonomic spectrum. We aim to promote standards that will facilitate comparative approaches to invertebrate genomics and collaborations across the international scientific community. Candidate study taxa include species from Porifera, Ctenophora, Cnidaria, Placozoa, Mollusca, Arthropoda, Echinodermata, Annelida, Bryozoa, and Platyhelminthes, among others. GIGA will target 7000 noninsect/nonnematode species, with an emphasis on marine taxa because of the unrivaled phyletic diversity in the oceans. Priorities for selecting invertebrates for sequencing will include, but are not restricted to, their phylogenetic placement; relevance to organismal, ecological, and conservation research; and their importance to fisheries and human health. We highlight benefits of sequencing both whole genomes (DNA) and transcriptomes and also suggest policies for genomic-level data access and sharing based on transparency and inclusiveness. The GIGA Web site () has been launched to facilitate this collaborative venture.
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Gonzalo M.A. Bermudez
2015-01-01
Full Text Available Este artículo se propone analizar los acontecimientos más relevantes de la historia de la Biología que le dieron corpus teórico y sustento científico, enfatizando el papel que cumplió la teoría de evolución de Lamarck y de Darwin en este proceso; y recopilar algunas de las problemáticas actuales asociadas con la enseñanza y el aprendizaje de la teoría de la evolución por selección natural. Inicialmente, los estudios sobre la vida recibieron fuertes críticas por una corriente de pensamiento originada en el Círculo de Viena en la segunda década del siglo pasado y que tuvo a la Física como modelo de ciencia. Según ésta, se promulgaba la existencia de un único método y explicación para los fenómenos naturales y sociales, reduciendo todo sistema a sus partes constituyentes. Los puntos de confrontación con la Biología se centraron en la escasez de leyes, la inutilización de la matemática en sus clasificaciones, y en la imposibilidad de falsar muchas de sus hipótesis, fundamentalmente las históricas. Con el tiempo, las nuevas corrientes de pensamiento en la Filosofía de las Ciencias reconocieron a la Biología por sus características distintivas y objetos de estudio propios, de complejidad irreductible y con un irrefutable espacio de acción para el azar y la probabilidad. A tal efecto, tanto Lamarck como Darwin realizaron significativos aportes al ofrecer una visión de la vida en transformación permanente. Sin embargo, fue la teoría de la evolución por selección natural de Darwin la que produjo una revolución científica al dar al mundo una explicación laica al origen de las especies. En el ámbito educativo, existen en la actualidad distintas dificultades para la enseñanza y el aprendizaje de la evolución, entre las que se destaca la presencia de numerosas concepciones alternativas a la postura científica tanto en docentes como en alumnos y manuales escolares. Se discuten las implicancias de la Biología y de
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Chichvarkhin, Anton
2017-01-01
A new sea star species, H. djakonovi sp.n., was discovered in Rudnaya Bay in the Sea of Japan. This is a sympatric species of the well-known and common species Henricia pseudoleviuscula Djakonov, 1958. Both species are similar in body size and proportions, shape of skeletal plates, and life coloration, which distinguishes them from the other Henricia species inhabiting the Sea of Japan. Nevertheless, these species can be distinguished by their abactinal spines: in both species, they are short and barrel-like, but the new species is the only Henricia species in Russian waters of the Pacific that possesses such spines with a massive, smooth, bullet-like tip. The spines in H. pseudoleviuscula are crowned with a variable number of well-developed thorns. About half (new species are oval, not crescent-shaped as in H. pseudoleviuscula .
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F Martín Blanco
2010-06-01
Full Text Available The 1983-1984 mass mortality event of Diadema antillarum affected more than 93% of the total Caribbean population. Although there are no records about the status of Diadema populations before and after die-off on Cuban reefs, anecdotal information suggests that populations were struck. We analyzed spatial variation in the abundance and size structure of D. antillarum in 22 reefs sites in Jardines de la Reina, from June 2004 to September 2005. Counts of Diadema were performed in five 30x2m transects at each sampling site and sampling time, and test diameters were measured in September 2005 at the same fore reefs. Abundances were higher at reef crests (mean densities 0.08-2.18 ind./m², while reef slope populations reached a maximum site level of 0.13 ind./m² at only one site and showed values up to three orders of magnitude lower than those from reef crests. Highest abundance occurred at the west margin of major channels between keys where larval recruitment seems to be favored by local oceanographic features and facilitated by the abundance of Echinometra lucunter. The size frequency distribution of D. antillarum indicates that recruitment began to be noticeable three years before September 2005, suggesting these populations were depleted in the past and they are recovering now. Rev. Biol. Trop. 58 (2: 663-676. Epub 2010 June 02.La mortalidad de Diadema antillarum en 1983-1984 afectó más del 93% de la población del Caribe. Aunque no existen datos publicados sobre el estado de sus poblaciones en arrecifes cubanos antes y después de la mortalidad, se conoce anecdóticamente que fueron afectadas. En el presente trabajo se analizan las variaciones espaciales de la abundancia y estructura de tallas de D. antillarum en 22 arrecifes frontales en Jardines de la Reina, para lo cual se realizaron cinco recorridos de 30x2m en cada sitio entre Junio de 2004 y Septiembre de 2005. Las densidades de Diadema fueron mayores en las crestas arrecifales (0.08-2.18 ind./m² mientras que en las pendientes fueron hasta tres órdenes de magnitud menor y la densidad máxima fue 0.13 ind./m². Las crestas con mayor abundancia de Diadema están ubicadas en los márgenes de las grandes pasas existentes entre cayos donde el reclutamiento parece estar favorecido por las condiciones oceanográficas locales y facilitado por la abundancia de Echinometra lucunter. La distribución de frecuencia de tallas de Diadema sugiere que el reclutamiento comenzó a ser notable aproximadamente tres años antes del muestreo, indicando que en el pasado sus poblaciones estuvieron afectadas y ahora están recuperándose.
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Claude Massin
2010-08-01
Full Text Available An undescribed species of Synallactes was collected during a deep-water benthic fauna survey off the Pacific coast of Mexico in the East Pacific, with the R/V El Puma. This new species differs from all the other known Synallactes by the presence of huge massive rods in the tube feet, some of them club-shaped. The later ossicle shape is unique among Holothuroidea. This is the first record of a Synallactes in the Gulf of California.
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International Nuclear Information System (INIS)
Nahon, Sarah; Castro Porras, Viviana A.; Pruski, Audrey M.; Charles, Francois
2009-01-01
The sea urchin Sphaerechinus granularis was used to investigate the impact of relevant levels of UV-B radiation on the early life stages of a common Mediterranean free spawning benthic species. Sperm, eggs and embryos were exposed to a range of UV radiation doses. The resulting endpoints were evaluated in terms of fertilisation success, development and survival rates. Above a weighted UV radiation dose of 0.0029 kJ m -2 , fertilisation capability of irradiated sperm decreased rapidly. The exposure of the eggs to 0.0175 kJ m -2 and more led to delayed and inhibited development with ensuing embryonic morphological abnormalities. One-day old larvae remained strongly sensitive to UV radiation as shown by the 50% decrease of the larval survival rate for a dose of 0.025 kJ m -2 UVR. The elevated sensitivity of embryos to experimental UVR went along with a lack of significant amount of sunscreen compounds (e.g., mycosporine-like amino acids) in the eggs. The present results demonstrated that gamete viability and embryonic development may be significantly impaired by solar UV radiation in S. granularis, compromising in this way the reproduction of the species. Unless adaptive behavioural reproductive strategies exist, the influence of ambient UV radiation appears as a selective force for population dynamics of broadcast spawners in the shallow benthic Mediterranean environment
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Energy Technology Data Exchange (ETDEWEB)
Nahon, Sarah [UPMC Univ Paris 06, UMR 7621, LOBB, Observatoire Oceanologique, F-66651, Banyuls/mer (France); CNRS, UMR 7621, LOBB, Observatoire Oceanologique, F-66651, Banyuls/mer (France); Castro Porras, Viviana A. [UPMC Univ Paris 06, UMR 7621, LOBB, Observatoire Oceanologique, F-66651, Banyuls/mer (France); Pruski, Audrey M. [UPMC Univ Paris 06, UMR 7621, LOBB, Observatoire Oceanologique, F-66651, Banyuls/mer (France); CNRS, UMR 7621, LOBB, Observatoire Oceanologique, F-66651, Banyuls/mer (France); Charles, Francois [UPMC Univ Paris 06, UMR 7621, LOBB, Observatoire Oceanologique, F-66651, Banyuls/mer (France); CNRS, UMR 7621, LOBB, Observatoire Oceanologique, F-66651, Banyuls/mer (France)], E-mail: charles@obs-banyuls.fr
2009-03-01
The sea urchin Sphaerechinus granularis was used to investigate the impact of relevant levels of UV-B radiation on the early life stages of a common Mediterranean free spawning benthic species. Sperm, eggs and embryos were exposed to a range of UV radiation doses. The resulting endpoints were evaluated in terms of fertilisation success, development and survival rates. Above a weighted UV radiation dose of 0.0029 kJ m{sup -2}, fertilisation capability of irradiated sperm decreased rapidly. The exposure of the eggs to 0.0175 kJ m{sup -2} and more led to delayed and inhibited development with ensuing embryonic morphological abnormalities. One-day old larvae remained strongly sensitive to UV radiation as shown by the 50% decrease of the larval survival rate for a dose of 0.025 kJ m{sup -2} UVR. The elevated sensitivity of embryos to experimental UVR went along with a lack of significant amount of sunscreen compounds (e.g., mycosporine-like amino acids) in the eggs. The present results demonstrated that gamete viability and embryonic development may be significantly impaired by solar UV radiation in S. granularis, compromising in this way the reproduction of the species. Unless adaptive behavioural reproductive strategies exist, the influence of ambient UV radiation appears as a selective force for population dynamics of broadcast spawners in the shallow benthic Mediterranean environment.
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Lirman
2000-08-23
Acropora palmata, a branching coral abundant on shallow reef environments throughout the Caribbean, is susceptible to physical disturbance caused by storms. Accordingly, the survivorship and propagation of this species are tied to its capability to recover after fragmentation. Fragments of A. palmata comprised 40% of ramets within populations that had experienced recent storms. While the survivorship of A. palmata fragments was not directly related to the size of fragments, removal of fragments from areas where they settled was influenced by size. Survivorship of fragments was also affected by type of substratum; the greatest mortality (58% loss within the first month) was observed on sand, whereas fragments placed on top of live colonies of A. palmata fused to the underlying tissue and did not experience any losses. Fragments created by Hurricane Andrew on a Florida reef in August 1992 began developing new growth (proto-branches) 7 months after the storm. The number of proto-branches on fragments was dependent on size, but growth was not affected by the size of fragments. Growth-rates of proto-branches increased exponentially with time (1.7 cm year(-1) for 1993-1994, 2.7 cm year(-1) for 1994-1995, 4.2 cm year(-1) for 1995-1996, and 6.5 cm year(-1) for 1996-1997), taking over 4 years for proto-branches to achieve rates comparable to those of adult colonies on the same reef (6.9 cm year(-1)). In addition to the initial mortality and reduced growth-rates, fragmentation resulted in a loss of reproductive potential. Neither colonies that experienced severe fragmentation nor fragments contained gametes until 4 years after the initial damage. Although A. palmata may survive periodic fragmentation, the long-term effects of this process will depend ultimately on the balance between the benefits and costs of this process.
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Alejandro Tagliafico
2012-09-01
Full Text Available Las estrellas de mar: Oreaster reticulatus y Luidia senegalensis, han sido objeto de escasos estudios en aguas venezolanas. Actualmente son consideradas especies amenazadas en diversas zonas del Caribe, Brasil y Colombia. Por esto, se planteó como objetivo generar información sobre su densidad poblacional, distribución y estructura de talla en los alrededores de la isla de Cubagua. Para ello, durante el año 2008, se realizaron cuatro transectas bandas de 50m2 cada una, en 52 estaciones ubicadas alrededor de la isla. Entre los resultados obtenidos para O. reticulatus destacan: 167.3ind/ha, un 33% inmaduros y 67% adultos con un promedio de tallas de 10.7±5cm (rango: 2.2-21cm; una amplia distribución en los alrededores de la isla, con mayores densidades en la zona este y suroeste. Luidia senegalensis mostró una densidad promedio de 40ind/ha, 95% superaba la talla de madurez reportada, con talla promedio de 12cm±3.5cm (rango: 3.5-22.3cm. Se recomienda realizar estudios de reproducción, así como monitoreos de sus densidades poblacionales que permitan inferir sus variaciones temporales.There is limited biological information about the starfish Oreaster reticulatus and the nine-armed starfish Luidia senegalensis in Venezuelan waters. These species are currently considered threatened in many localities of the Caribbean, Brazil and Colombia. Therefore, the aim of this study was to describe their population density, size distribution and population structure in Cubagua Island. During 2008, 52 stations located around the island were evaluated using band transects of 50m2. Each organism was counted and measured (maximum radius, and its size was compared to the maturity length reported in the literature. The results for O. reticulatus include: 167.3ind./ha; 33% juveniles and 67% adults; average size of 10.7±5cm (range: 2.2-21cm; a wide distribution around the island, with higher densities in the Eastern and Southwest areas. The 50% of the specimens were found in seagrass beds, 25% in sand, 16% in areas covered by decomposed seaweeds, 9% in oyster beds and 1% coralline patches. The densities of O. reticulatus were higher than those reported in the Caribbean, Panama and Puerto Rico, but lower than Venezuelan National Parks: Mochima and Morrocoy; as well as in the Virgin Islands and Belize. For L. senegalensis we found an average density of 40ind./ha; 95% exceeded the reported size at maturity, with mean length of 12cm±3.5cm (range: 3.5-22.3cm; they were found only in 15% of the stations of which 92.5% were sandy bottoms and the other 7.5% oyster beds. The degree of aggregation of L. senegalensis was greater than O. reticulatus, with an estimated k of 0.06. However, it was not possible to compare the densities of L. senegalensis with any other study. For both species is recommended to carry out reproductive studies and to monitor their population densities to infer temporal variations.
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Seagrass community dynamics in a subtropical estuarine lagoon
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Thorhaug, A.; Roessler, M.A.
1977-11-01
The temporal and spatial distributions of major plant and animal species were investigated for 4 years in south Biscayne Bay including Card Sound, Florida, a subtropical estuarine lagoon. This was part of a larger study including chemical, physical and geological investigations. The major species of plants were Thalassia testudinum Banks ex Konig, turtle grass, Laurencia poitei (Lamour.) Howe, a red macroalga and the green algae Penicillus capitatus Lamarck and Halimeda incrassata (Ellis) Lamour. Standing crop and production of plant material taken bi-weekly is given in detail for 16 stations in Card Sound for the 4-year period and for eight stations in Biscayne Bay for a 1-year period. The major animal species were not equally distributed; in the near-shore Thalassia community, species of Pagurus, Neopanope, Hippolyte, Cerithium, Bulla, Prunum and Modulus were dominant. In mid-bay, where patchy Thalassia plus green algae occurred, Thor and Chondrilla were the dominant animals. Near the fringing islands, where tidal flow caused more oceanic conditions, the community was dominated by sponges, urchins and corals. This highlights the structural differences in what is now termed the ''Thalassia community.'' Comparisons with other known Thalassia communities are made.
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Bento CAVADAS
2011-11-01
Full Text Available The teaching of evolution in the Portuguese secondary schools is not yet fully understood. This research aimed to contribute to this clarification, in the framework of the history of the curriculum and the biology subject, by showing the expressions of the evolutionism teaching in the first three decades of the twentieth century. To this end we analyzed the programs of Zoology of 1905 and 1919, as well as two textbooks, entitled «Lições de Zoologia» and written by Bernardo Aires in accordance with these programs. This analysis showed that the study of evolution, eliminated from the program in 1905, was again recognized in the program in 1919. In textbooks, the exposure of evolution focused on the subject of evolution, in the grounds of competition and natural selection, adaptation, the biogenetic law and the essential differences between Lamarckism and Darwinism. The comparative study of these textbooks showed that the text which addresses the evolution is essentially Darwinian. However, neoLamarckians sections have been identified that show the influence of the «eclipse of Darwinism» on the teaching of evolutionism.
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Govorin I. A.
2016-06-01
Full Text Available The data of the size-mass indices in the mussels Mytilus galloprovincialis (Lamarck, 1819 from three phenotypic groups - brown, dark violet (black and “zebra” (brown with radial black stripes shells in the periphyton settlements on the concrete traverses near Odessa coast, the North-western part of Black Sea (Ukraine, in March-November 2014-2015 are presented. A comparative evaluation has been made on the relationships of total mass of the mollusks, wet and dry mass of their soft body and mass of the shells on the one hand, and the size of animals (length of its shells on the other hand, in the each of phenotypical groups from the five marine beach areas. It is shown, that in the marine areas with different degrees of isolation from the open sea by coast-protection engineering constructions, the mussels from different phenotypes have almost the same size-mass characteristics. Only the dry weight of soft animal body, which indicated to fatness of mollusk and therefore demonstrated his biological prosperity in specific hydrological conditions, can serve as a reliable criterion which can mark the shellfish habitats with different gradients of environmental factors.
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Pawson, David L
2018-02-07
Astrophiura caroleae, new species, is described from off Curacao in the southern Caribbean, and from the western Gulf of Mexico, in depths of 244 to 434 meters. This new species, the first in the genus Astrophiura to be described from the Atlantic Ocean, has a distinctive combination of characters, including regularly arranged primary plates, large radial shields whose radial edges are in contact for their entire visible length, and prominent tubercles on central and radial plates. The mottled reddish coloration of the dorsal surface of this species usually contrasts with the color of the substratum, rendering it readily visible in situ, despite its disc diameter of less than 10 mm. Like its congeners, A. caroleae is gonochoric, the gonads of females containing conspicuous masses of bright orange eggs that are approximately 165 µm in diameter. DNA Barcoding data are provided for this new species, these are the first for Astrophiura.
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Dewi, N. N.; Pursetyo, K. T.; Aprilianitasari, L.; Zakaria, M. H.; Ramadhan, M. R.; Triatmaja, R. A.
2018-04-01
This study aims to determine the biomass, density, and distribution patterns of Asterias sp. Samples were collected from three locations such as Wonokromo, Dadapan and Juanda, each divided into 3 zones. In each zone, samples were taken as many as 5 repetitions using swept area method. Temporarily, the highest biomass of starfish was 2.95 gr/m2 in Dadapan Zone on January. Spatially, biomass of starfish was found in Dadapan Zone (3,35 gr/m2). Similarly, the high density was also found in Dadapan Zone on January (9 ind/10 m2). In general, the distributionpattern of starfish in East Coast Surabaya throughspatial and temporal showed that the pattern of starfish was grouping distribution (Id value > 1) for Dadapan and Juanda, and uniform for Wonokromo. Oceanographic condition, antropogenic activity, and water quality in East Cost of Surabaya become important things which is affected the biomass, densityand distribution pattern of starfish. The knowledge of starfish biomass and density is very important given that this biota has ecological value as a balancing ecosystem in the waters.
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Grondona Jesus M
2009-06-01
Full Text Available Abstract Background Echinoderms and chordates belong to the same monophyletic taxon, the Deuterostomia. In spite of significant differences in body plan organization, the two phyla may share more common traits than was thought previously. Of particular interest are the common features in the organization of the central nervous system. The present study employs two polyclonal antisera raised against bovine Reissner's substance (RS, a secretory product produced by glial cells of the subcomissural organ, to study RS-like immunoreactivity in the central nervous system of sea cucumbers. Results In the ectoneural division of the nervous system, both antisera recognize the content of secretory vacuoles in the apical cytoplasm of the radial glia-like cells of the neuroepithelium and in the flattened glial cells of the non-neural epineural roof epithelium. The secreted immunopositive material seems to form a thin layer covering the cell apices. There is no accumulation of the immunoreactive material on the apical surface of the hyponeural neuroepithelium or the hyponeural roof epithelium. Besides labelling the supporting cells and flattened glial cells of the epineural roof epithelium, both anti-RS antisera reveal a previously unknown putative glial cell type within the neural parenchyma of the holothurian nervous system. Conclusion Our results show that: a the glial cells of the holothurian tubular nervous system produce a material similar to Reissner's substance known to be synthesized by secretory glial cells in all chordates studied so far; b the nervous system of sea cucumbers shows a previously unrealized complexity of glial organization. Our findings also provide significant clues for interpretation of the evolution of the nervous system in the Deuterostomia. It is suggested that echinoderms and chordates might have inherited the RS-producing radial glial cell type from the central nervous system of their common ancestor, i.e., the last common ancestor of all the Deuterostomia.
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Félix Martín Blanco
2011-09-01
Full Text Available The 1983-1984 mass mortality of Diadema antillarum produced severe damages on Caribbean reefs contributing to substantial changes in community structure that still persist. Despite the importance of Diadema grazing in structuring coral reefs, available information on current abundances and algal-urchin interactions in Cuba is scarce. We analyzed spatial variations in Diadema abundance and its influence on algal community structure in 22 reef sites in Jardines de la Reina, in June/2004 and April/2005. Urchins were counted in five 30x2m transects per site, and algal coverage was estimated in randomly located 0.25m side quadrats (15 per site. Abundances of Diadema were higher at reef crests (0.013-1.553 ind/m², while reef slope populations showed values up to three orders of magnitude lower and were overgrown by macroalgae (up to 87%, local values. Algal community structure at reef slopes were dominated by macroalgae, especially Dictyota, Lobophora and Halimeda while the most abundant macroalgae at reef crests were Halimeda and Amphiroa. Urchin densities were negatively and positively correlated with mean coverage of macroalgae and crustose coralline algae, respectively, when analyzing data pooled across all sites, but not with data from separate habitats (specially reef crest, suggesting, along with historical fish biomass, that shallow reef community structure is being shaped by the synergistic action of other factors (e.g. fish grazing rather than the influence of Diadema alone. However, we observed clear signs of Diadema grazing at reef crests and decreased macroalgal cover according to 2001 data, what suggest that grazing intensity at this habitat increased at the same time that Diadema recruitment began to be noticeable. Furthermore, the excessive abundance of macroalgae at reef slopes and the scarcity of crustose coralline algae seems to be due by the almost complete absence of D. antillarum at mid depth reefs, where local densities of this urchin were predominantly low. Rev. Biol. Trop. 59 (3: 1149-1163. Epub 2011 September 01.A pesar de la importancia del forrageo de Diadema en la estructuración de los arrecifes de coral, la información disponible sobre la actual abundancia de algas y de las interacciones de erizos en Cuba es escasa. Por lo tanto, se analizan las variaciones espaciales en la abundancia de Diadema antillarum y su influencia sobre las algas en 22 arrecifes en Jardines de la Reina, en junio/2004 y abril/2005. Los erizos se muestrearon en recorridos de 30x2m (5/sitio y las algas en cuadrículas de 0.25m de lado (15/sitio. Las densidades de Diadema fueron mayores en las crestas arrecifales (0.013-1.553ind/m² mientras que las pendientes mostraron valores hasta tres ordenes de magnitud menor y presentaron un cubrimiento excesivo de macroalgas (hasta 87%, siendo las más abundantes Dictyota, Lobophora y Halimeda. Las densidades de erizos estuvieron correlacionadas negativa y positivamente con el cubrimiento de macroalgas y algas costrosas, respectivamente, en el análisis global, pero no en hábitats separados (especialmente en crestas, sugiriendo, conjuntamente con la biomasa histórica de peces, que la estructura de las comunidades en las crestas está determinada por la acción sinérgica de otros factores (herbivoría de peces más que por la influencia de Diadema solo. No obstante, se observaron indicios del forrajeo de Diadema, y el cubrimiento de macroalgas disminuyó desde 2001, lo cual sugiere que la intensidad de la herbivoría aumentó al mismo tiempo que el reclutamiento de Diadema.
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Alitto, Renata A S; Bueno, Maristela L; Guilherme, Pablo D B; Di Domenico, Maikon; Christensen, Ana Beardsley; Borges, Michela
2018-04-05
The detailed study of arm ossicles, particularly the lateral arm plates, is providing valuable information in the elucidation of ophiuroid taxonomy. The present study describes in detail 16 species of brittle stars from Araçá Bay, Brazil. This information is used to construct the first interactive electronic key, providing a valuable resource for a broad range of researchers. Brittle stars families were divided into three groups based on their spatial distribution: i) infaunal species of intertidal and shallow subtidal belonging to Amphiuridae and Ophiactidae, ii) epizoic species belonging to Amphiuridae, Ophiactidae, and Ophiotrichidae and, iii) epifaunal species of the subtidal belonging to Ophiodermatidae and Hemieuryalidae. In the global context of recent revisions of ophiuroid taxonomy, the present work provides additional characters for use in future phylogenetic studies.
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Anticancer Activity of Sea Cucumber Triterpene Glycosides
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Dmitry L. Aminin
2015-03-01
Full Text Available Triterpene glycosides are characteristic secondary metabolites of sea cucumbers (Holothurioidea, Echinodermata. They have hemolytic, cytotoxic, antifungal, and other biological activities caused by membranotropic action. These natural products suppress the proliferation of various human tumor cell lines in vitro and, more importantly, intraperitoneal administration in rodents of solutions of some sea cucumber triterpene glycosides significantly reduces both tumor burden and metastasis. The anticancer molecular mechanisms include the induction of tumor cell apoptosis through the activation of intracellular caspase cell death pathways, arrest of the cell cycle at S or G2/M phases, influence on nuclear factors, NF-κB, and up-down regulation of certain cellular receptors and enzymes participating in cancerogenesis, such as EGFR (epidermal growth factor receptor, Akt (protein kinase B, ERK (extracellular signal-regulated kinases, FAK (focal adhesion kinase, MMP-9 (matrix metalloproteinase-9 and others. Administration of some glycosides leads to a reduction of cancer cell adhesion, suppression of cell migration and tube formation in those cells, suppression of angiogenesis, inhibition of cell proliferation, colony formation and tumor invasion. As a result, marked growth inhibition of tumors occurs in vitro and in vivo. Some holothurian triterpene glycosides have the potential to be used as P-gp mediated MDR reversal agents in combined therapy with standard cytostatics.
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Javier Chazarreta
2015-06-01
Full Text Available Abstract The short-term variability of mesozooplankton distribution and physicochemical variables was examined in two different channels of the Bahía Blanca Estuary, Argentina, during two tidal cycles. All the physicochemical measurements and mesozooplankton sampling were performed at a fixed site during approximately 22-23 h at 3-h intervals. Pumps were used to obtain surface and bottom mesozooplankton samples and the water speed of each stratum was measured with an Acoustic Doppler Current Profiler (ADCP. In all, 23 mesozooplanktonic taxa belonging to four phyla (Arthropoda, Annelida, Echinodermata and Chordata were identified. The most abundant taxa during the two tidal cycles were Balanus glandula larvae, Eurytemora americana and Acartia tonsa. A discernible variability in the water conditions and vertical mesozooplankton distribution (VMD different from that known for the estuary's main channel, was found in the other two selected channels. VMD varied during the tidal cycle in both channels in accordance with the channel's geomorphology and water dynamic characteristics of each of them. The variation of the abundance of the different taxa during ebb and flood currents might indicate the existence of a tidal vertical migration of the mesozooplankton as a response to particular dynamic water conditions.
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An updated checklist of Echinoderms from Indian waters.
Samuel, Vijay Kumar Deepak; Krishnan, Pandian; Sreeraj, Chemmencheri Ramakrishnan; Chamundeeswari, Kanagaraj; Parthiban, Chermapandi; Sekar, Veeramuthu; Patro, Shesdev; Saravanan, Raju; Abhilash, Kottarathil Rajendran; Ramachandran, Purvaja; Ramesh, Ramachandran
2017-11-27
Species checklists enlist the species available within the defined geographical region and thus serve as essential input for developing conservation and management strategies. The fields of conservation biology and ecology confront the challenge of inflated biodiversity, attributed to non-recognition of taxonomic inconsistencies such as synonyms, alternate representation, emendations etc. Critical review of the checklists and distributional records of Phylum Echinodermata from Indian waters and subsequent validation of species names with World Register of Marine Species (WoRMS) database, revealed that the current literature included 236 incorrect entries comprising of 162 synonyms, 15 emendations, 5 nomina dubia, 1 nomen nudum, 40 species under alternate representation, 9 species with author misnomer, 1 subspecies and 1 unaccepted. The 226 species found to be mixed with valid names and a revised checklist was prepared. The revised and updated checklist holds 741 species of echinoderms comprising of 182 asteroids (24.56%), 70 crinoids (9.45%), 138 echinoids (18.62%), 179 holothuroids (24.16%) and 172 ophiuroids (23.21%), placed under 28 orders and 107 families. This paper discusses the cause for taxonomic inflation and argues that such taxonomic inconsistencies alter our interpretations of a species including its inaccurate distribution and, could possibly impede the country's conservation and management efforts.
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Soft-bottom macrobenthic faunal associations in the southern Chilean glacial fjord complex
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Carlos Ríos
2005-12-01
Full Text Available Macrobenthic associations were investigated at 29 sampling stations with a semi-quantitative Agassiz trawl, ranging from the South Patagonian Icefield to the Straits of Magellan in the South Chilean fjord system. A total of 1,895 individuals belonging to 131 species were collected. 19 species belong to colonial organisms, mainly Bryozoa (17 species and Octocorallia (2 species. The phylum Echinodermata was the most diverse in species number (47 species, with asteroids (25 species and ophiuroids (13 species being the best represented within this taxon. Polychaeta was the second dominant group in terms of species richness (46 species. Multidimensional scaling ordination (MDS separated two station groups, one related to fjords and channels off the South Patagonian Icefield and the second one to stations surrounding the Straits of Magellan. 45 species account for 90% of the dissimilarity between these two groups. These differences can mainly be explained by the influence of local environmental conditions determined by processes closely related to the presence/absence of glaciers. Abiotic parameters such as water depth, type of sediment and chemical features of the superficial sediment were not correlated with the numbers of individuals caught by the Agassiz trawl in each group of sampling stations.
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Ítalo Braga de Castro
2004-06-01
Full Text Available The use of antifouling paints containing the biocide compound tributyltin (TBT has been shown as an inductor of imposex in neogastropods mollusks. Imposex is characterized by the development of male features in females, mainly the appearance of a no functional vas deferens and penis. Samples of Thais rustica were collected in eight sites in the metropolitan area of Natal city, Rio Grande do Norte state, northeast Brazil, and examined for occurrence of imposex, which was found in many females. The higher imposex levels were presented by samples from sites near city harbor.A utilização de tintas antiincrustrantes contendo o composto biocida tributilestanho (TBT tem induzido moluscos neogastrópodes ao imposex. O imposex é caracterizado pelo surgimento de caracteres sexuais masculinos, sobretudo, pênis e vaso deferente não funcionais em fêmeas desses moluscos. Foram coletadas amostras de Thais rústica em oito estações ao longo da costa da cidade de Natal no Rio Grande do Norte. Esses animais foram analisados quanto a presença e o grau de imposex que apresentavam. Os níveis mais elevados de imposex foram observados na estação mais próxima ao porto.
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Allan Joseph Bright
2016-05-01
Full Text Available Disturbances such as tropical storms cause coral mortality and reduce coral cover as a direct result of physical damage. Storms can be one of the most important disturbances in coral reef ecosystems, and it is crucial to understand their long-term impacts on coral populations. The primary objective of this study was to determine trends in disease prevalence and snail predation on damaged and undamaged colonies of the threatened coral species, Acropora palmata, following an episode of heavy ocean swells in the US Virgin Islands (USVI. At three sites on St. Thomas and St. John, colonies of A. palmata were surveyed monthly over one year following a series of large swells in March 2008 that fragmented 30 to 93% of colonies on monitored reefs. Post-disturbance surveys conducted from April 2008 through March 2009 showed that swell-generated damage to A. palmata caused negative indirect effects that compounded the initial direct effects of physical disturbance. During the 12 months after the swell event, white pox disease prevalence was 41% higher for colonies that sustained damage from the swells than for undamaged colonies (df = 207, p = 0.01 with greatest differences in disease prevalence occurring during warm water months. In addition, the corallivorous snail, Coralliophila abbreviata, was 46% more abundant on damaged corals than undamaged corals during the 12 months after the swell event (df = 207, p = 0.006.
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Muller, E. M.; Rogers, C. S.; Spitzack, A. S.; van Woesik, R.
2008-03-01
Anomalously high water temperatures may enhance the likelihood of coral disease outbreaks by increasing the abundance or virulence of pathogens, or by increasing host susceptibility. This study tested the compromised-host hypothesis, and documented the relationship between disease and temperature, through monthly monitoring of Acropora palmata colonies from May 2004 to December 2006, in Hawksnest Bay, St John, US Virgin Islands (USVI). Disease prevalence and the rate of change in prevalence showed a positive linear relationship with water temperature and rate of change in water temperature, respectively, but only in 2005 during prolonged periods of elevated temperature. Both bleached and unbleached colonies showed a positive relationship between disease prevalence and temperature in 2005, but the average area of disease-associated mortality increased only for bleached corals, indicating host susceptibility, rather than temperature per se, influenced disease severity on A. palmata.
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V. M. A. Camilo
2017-08-01
Full Text Available Abstract Mytella guyanensis, consumed and commercialized in coastal regions of Brazil, is one of several bivalve species of socioeconomic interest for coastal communities. Besides serving as a source of income and subsistence for these communities, it also contributes to their food security as it is a source of proteins and micronutrients. Thus, the reproductive cycle of this species was studied aiming to contribute to food security and its preservation. Samples were collected monthly, between March 2014 and March 2015, in a natural stock (12°38'50”S; 38°51'43”W in a Marine Reserve (RESEX Bay of Iguape (community Engenho da Ponte, Bahia, Brazil. Mytella guyanensis is collected by women on site, where the artisanal fishing of this resource is performed without following any specific handling procedure. Also, empirical evidence indicates overexploitation. The specimens collected were measured along the anterior-posterior axis (length, and after macroscopic analysis they were fixed in Davidson solution, processed by routine histology techniques and stained with Harris haematoxylin and eosin (H&E. The macroscopic analysis showed sexual dimorphism, with the male and female gonads presenting a milky-white and orange colour, respectively. A 1:1 sex ratio (M: F was observed and reproduction of the species was continuous all year round. March, April, July and August were the months with highest values of gamete elimination. We suggest that a M. guyanensis management plan should restrict capture during these months, in order to sustainably regulate exploitation of this food resource in this reserve.
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Bright, Allan J.; Rogers, Caroline S.; Brandt, Marilyn E.; Muller, Erinn; Smith, Tyler B.
2016-01-01
Disturbances such as tropical storms cause coral mortality and reduce coral cover as a direct result of physical damage. Storms can be one of the most important disturbances in coral reef ecosystems, and it is crucial to understand their long-term impacts on coral populations. The primary objective of this study was to determine trends in disease prevalence and snail predation on damaged and undamaged colonies of the threatened coral species, Acropora palmata, following an episode of heavy ocean swells in the US Virgin Islands (USVI). At three sites on St. Thomas and St. John, colonies of A. palmata were surveyed monthly over 1 year following a series of large swells in March 2008 that fragmented 30–93% of colonies on monitored reefs. Post-disturbance surveys conducted from April 2008 through March 2009 showed that swell-generated damage to A. palmata caused negative indirect effects that compounded the initial direct effects of physical disturbance. During the 12 months after the swell event, white pox disease prevalence was 41% higher for colonies that sustained damage from the swells than for undamaged colonies (df = 207, p = 0.01) with greatest differences in disease prevalence occurring during warm water months. In addition, the corallivorous snail, Coralliophila abbreviata, was 46% more abundant on damaged corals than undamaged corals during the 12 months after the swell event (df = 207, p = 0.006).
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Argus Vasconcelos de Almeida
2005-04-01
Full Text Available O presente trabalho tenta estabelecer uma complementaridade teórica entre uma abordagem epistemológica - a metodologia dos programas de pesquisa de Lakatos - e uma psicológico-cognitivista - a teoria dos campos conceituais de Vergnaud - objetivando a compreensão dos programas de pesquisa lamarckiano e darwiniano em seus respectivos campos de validade. Através da análise da estrutura histórico-conceitual dos dois programas e sua transposição para o ambiente escolar, são constatados e discutidos problemas nos livros didáticos de Biologia e na pesquisa atual sobre o conceito de Evolução entre alunos de diversos níveis escolares. Como resultado destas reflexões é apontada a teoria dos campos conceituais como um instrumento analítico frutífero do processo de conceitualização dos sujeitos diante de situações envolvendo processos evolutivos.The present work tries to establish a theoretical similarities in complementary among an epistemological approaches between - the methodology of the programs of research of Lakatos - and (a psychological-cognitivist and - the theory of the conceptual fields of Vergnaud. It - aimsing at the understanding of the programs of research Llamarckian and Ddarwinian programmes of research in theirr respective validity fields. Through the analysis of the historical-conceptual structure of the two programs and itsyour conversion for the school environment, verified and discussed problems in the text books of Biology are identified and discussed as is and in the current research on the concept of Evolution among students atof several school levels. As a result of these reflections the theory of the conceptual fields is pointed out as a fruitful analytical instrument of the conceptualization process inof the subjects front to situations involving evolutionary processes.
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Argus Vasconcelos de Almeida; Jorge Tarcisio da Rocha Falcão
2005-01-01
O presente trabalho tenta estabelecer uma complementaridade teórica entre uma abordagem epistemológica - a metodologia dos programas de pesquisa de Lakatos - e uma psicológico-cognitivista - a teoria dos campos conceituais de Vergnaud - objetivando a compreensão dos programas de pesquisa lamarckiano e darwiniano em seus respectivos campos de validade. Através da análise da estrutura histórico-conceitual dos dois programas e sua transposição para o ambiente escolar, são constatados e discutido...
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Yulihatul Meisaroh
2018-02-01
Full Text Available Serangan Island is a small island located approximately 5 km in south of Denpasar City and has a maximum length of 2.9 km and a width of 1 km which is administratively as part of the Denpasar City, Bali Province. Serangan Island is widely used for aquaculture and fisheries activities, moreover Serangan is also used as tourism activities, transportation routes, the harbour of ships and residences which may have impact on the aquatic ecosystem balance. The purpose of this research is to know how the structure of macrozoobenthos community and the water quality condition in Serangan Island. The research was conducted on February to March 2017 by using descriptive quantitative method in 3 research stasions. The result showed that there are 23 species of macrozoobenthos that consists of 7 classes, namely Gastropods, Bivalve, Crustacea, Echinoidea, Asteroidea, Ophiuroidea, and Holothuroidea. The highest total of abundance was at station 1 about 46,8 ind/m2. The diversity index ranged from 0,66-2,14 and the equibility index ranged from 0,60-0,81, while the dominance index ranged from 0,17-0,63. Based on the criteria of the Shanon-Wiener diversity index (H', the diversity index at station 1 and 2 indicates moderate diversity which has moderate species distribution and moderately polluted waters, whereas the value of the diversity index at station 3 indicates that the diversity in this stasion is low, showed by low abundance of species, low stability of the community and severe polluted condition.
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Sohtome, Tadahiro; Wada, Toshihiro; Mizuno, Takuji; Nemoto, Yoshiharu; Igarashi, Satoshi; Nishimune, Atsushi; Aono, Tatsuo; Ito, Yukari; Kanda, Jota; Ishimaru, Takashi
2014-12-01
Radioactive cesium ((134)Cs and (137)Cs) concentrations in invertebrates of benthic food web (10 taxonomic classes with 46 identified families) collected from wide areas off Fukushima Prefecture (3-500 m depth) were inspected from July 2011, four months after the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident, to August 2013 to elucidate time-series trends among taxa and areas. Cesium-137 was detected in seven classes (77% of 592 specimens). Higher (137)Cs concentrations within detected data were often found in areas near or south of the FDNPP, which is consistent with the reported spatial distribution of (137)Cs concentrations in highly contaminated seawater and sediments after the FDNPP accident. Overall (137)Cs concentrations in invertebrates, the maxima of which (290 Bq kg(-1)-wet in the sea urchin Glyptocidaris crenularis) were lower than in many demersal fishes, had decreased exponentially with time, and exhibited taxon-specific decreasing trends. Concentrations in Bivalvia and Gastropoda decreased clearly with respective ecological half-lives of 188 d and 102 d. In contrast, decreasing trends in Malacostraca and Polychaeta were more gradual, with longer respective ecological half-lives of 208 d and 487 d. Echinoidea showed no consistent trend, presumably because of effects of contaminated sediments taken into their digestive tract. Comparison of (137)Cs concentrations in the invertebrates and those in seawater and sediments suggest that contaminated sediments are the major source of continuing contamination in benthic invertebrates, especially in Malacostraca and Polychaeta. Copyright © 2014 Elsevier Ltd. All rights reserved.
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Marcela Cantillánez
2010-01-01
Full Text Available En una granja marina ubicada colindante con el área de reserva marina “La Rinconada” (Antofagasta, Chile, se evaluó el asentamiento larval del pectínido Argopecten purpuratus sobre colectores impregnados con películas multi-específicas, de las diatomeas Navicula sp. y Amphora sp., y de la cepa bacteriana NC1, aisladas desde colectores utilizados en captaciones comerciales de esta especie que presentaron altos índices de fijación, y que bajo condiciones controladas de criadero y laboratorio, han mostrando altos niveles de asentamiento larval. Los resultados obtenidos con el uso de estas biopelículas, sobre colectores instalados en forma paralela a los utilizados por la empresa para la captación de semilla con fines comerciales, no mostraron diferencias significativas entre los diferentes tratamientos probados y el control, respecto a las fijaciones ocurridas en un lapso de 30 días de inmersión. Se discute, debido a los tiempos que demandaron las larvas de la primera cohorte en asentarse sobre los colectores tratados, un posible reemplazo de las biopelículas utilizadas, por otra común en todos ellos y atractiva para el asentamiento de las larvas, como causa de la ausencia de efectos significativos de los tratamientos probados en el medio natural. Se recomienda la necesidad de establecer el tiempo de permanencia, en el ambiente natural, de las biopelículas impregnadas a los colectores en laboratorio.In a commercial farm located near the Marine Reserve “La Rinconada” (Antofagasta, Chile the larval settlement of Argopecten purpuratus on artificial collectors impregnated with multiespecific films of marine diatoms Navicula sp. and Amphora sp. and, bacterial strain NC1 were evaluated, These biofilms were isolates from artificial collector used in commercial activities with highest index of settlement in hatchery and laboratory conditions. The results to use this biofilms in collectors installed in same condition of commercial collectors show not statistical differences between treatment uses and the control based on the number of larvae for collectors after about 30 days of immersion. This differences observed, in base to time necessary to settle of larvae to first cohort on collector, is product of possible replacement of this biofilms for a common type in all collectors and more attractive for larval settlement. We recommend to estimate the time to replace the biofilms on artificial collectors installed in natural environment.
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Malgorzata Baranowska
2011-01-01
Full Text Available The sea cucumber Holothuria forskåli possesses a specialized system called Cuvierian tubules. During mechanical stimulation white filaments (tubules are expelled and become sticky upon contact with any object. We isolated a protein with adhesive properties from protein extracts of Cuvierian tubules from H. forskåli. This protein was identified by antibodies against recombinant precollagen D which is located in the byssal threads of the mussel Mytilus galloprovincialis. To find out the optimal procedure for extraction and purification, the identified protein was isolated by several methods, including electroelution, binding to glass beads, immunoprecipitation, and gel filtration. Antibodies raised against the isolated protein were used for localization of the adhesive protein in Cuvierian tubules. Immunostaining and immunogold electron microscopical studies revealed the strongest immunoreactivity in the mesothelium; this tissue layer is involved in adhesion. Adhesion of Cuvierian tubule extracts was measured on the surface of various materials. The extracted protein showed the strongest adhesion to Teflon surface. Increased adhesion was observed in the presence of potassium and EDTA, while cadmium caused a decrease in adhesion. Addition of antibodies and trypsin abolished the adhesive properties of the extract.
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Okanishi, Masanori; Fujita, Toshihiko; Maekawa, Yu; Sasaki, Takenori
2017-01-01
The first morphological observation of a euryalid brittle star, Asteronyx loveni , using non-destructive X-ray micro-computed tomography (µCT) was performed. The body of euryalids is covered by thick skin, and it is very difficult to observe the ossicles without dissolving the skin. Computed tomography with micrometer resolution (approximately 4.5-15.4 µm) was used to construct 3D images of skeletal ossicles and soft tissues in the ophiuroid's body. Shape and positional arrangement of taxonomically important ossicles were clearly observed without any damage to the body. Detailed pathways inside the vertebral ossicles, lateral arm plates, and arm spines for passage of nerves and water vascular structures were observed. Inter-vertebral muscles were also observed. Forms and 3D arrangements of many important taxonomical characters of the euryalids were scrutinized by µCT in high enough resolution for taxonomic description of ophiuroids.
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Massanori Okanishi
2017-03-01
Full Text Available The first morphological observation of a euryalid brittle star, Asteronyx loveni, using non-destructive X-ray micro-computed tomography (µCT was performed. The body of euryalids is covered by thick skin, and it is very difficult to observe the ossicles without dissolving the skin. Computed tomography with micrometer resolution (approximately 4.5–15.4 µm was used to construct 3D images of skeletal ossicles and soft tissues in the ophiuroid’s body. Shape and positional arrangement of taxonomically important ossicles were clearly observed without any damage to the body. Detailed pathways inside the vertebral ossicles, lateral arm plates, and arm spines for passage of nerves and water vascular structures were observed. Inter-vertebral muscles were also observed. Forms and 3D arrangements of many important taxonomical characters of the euryalids were scrutinized by µCT in high enough resolution for taxonomic description of ophiuroids.
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Ben Thuy
Full Text Available Ophiuroid systematics is currently in a state of upheaval, with recent molecular estimates fundamentally clashing with traditional, morphology-based classifications. Here, we attempt a long overdue recast of a morphological phylogeny estimate of the Ophiuroidea taking into account latest insights on microstructural features of the arm skeleton. Our final estimate is based on a total of 45 ingroup taxa, including 41 recent species covering the full range of extant ophiuroid higher taxon diversity and 4 fossil species known from exceptionally preserved material, and the Lower Carboniferous Aganaster gregarius as the outgroup. A total of 130 characters were scored directly on specimens. The tree resulting from the Bayesian inference analysis of the full data matrix is reasonably well resolved and well supported, and refutes all previous classifications, with most traditional families discredited as poly- or paraphyletic. In contrast, our tree agrees remarkably well with the latest molecular estimate, thus paving the way towards an integrated new classification of the Ophiuroidea. Among the characters which were qualitatively found to accord best with our tree topology, we selected a list of potential synapomorphies for future formal clade definitions. Furthermore, an analysis with 13 of the ingroup taxa reduced to the lateral arm plate characters produced a tree which was essentially similar to the full dataset tree. This suggests that dissociated lateral arm plates can be analysed in combination with fully known taxa and thus effectively unlocks the extensive record of fossil lateral arm plates for phylogenetic estimates. Finally, the age and position within our tree implies that the ophiuroid crown-group had started to diversify by the Early Triassic.
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Billett, D. S. M.; Hansen, B.
1982-07-01
Kolga hyalina Danielssen and Koren has been found in dense numbers between 2755 and 4080 m in the Porcupine Seabight. All of the specimens were small and of a similar size at any one station. The narrow size distributions were typical of the species over a wide geographic area and size range. Gonadial development is evident in the smallest specimens examined (3 mm long). The life-history traits of K. hyalina are discussed in relation to its association with the unstable environment of the Gollum Channel system. The dispersion pattern of K. hyalina changed temporally and, to a lesser extent, spatially. In some cases dense aggregations were formed. Taxonomic details are also presented.
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Schillaci, Domenico; Cusimano, Maria Grazia; Cunsolo, Vincenzo; Saletti, Rosaria; Russo, Debora; Vazzana, Mirella; Vitale, Maria; Arizza, Vincenzo
2013-06-24
The present study aims to investigate coelomocytes, immune mediators cells in the echinoderm Holothuria tubulosa, as an unusual source of antimicrobial and antibiofilm agents. The activity of the 5kDa peptide fraction of the cytosol from H. tubulosa coelomocytes (5-HCC) was tested against a reference group of Gram-negative and Gram-positive human pathogens. Minimal inhibitory concentrations (MICs) ranging from 125 to 500 mg/ml were determined against tested strains. The observed biological activity of 5-HCC could be due to two novel peptides, identified by capillary RP-HPLC/nESI-MS/MS, which present the common chemical-physical characteristics of antimicrobial peptides. Such peptides were chemically synthesized and their antimicrobial activity was tested. The synthetic peptides showed broad-spectrum activity at 12.5 mg/ml against the majority of the tested Gram-positive and Gram-negative strains, and they were also able to inhibit biofilm formation in a significant percentage at a concentration of 3.1 mg/ml against staphylococcal and Pseudomonas aeruginosa strains.The immune mediators in H. tubulosa are a source of novel antimicrobial peptides for the development of new agents against biofilm bacterial communities that are often intrinsically resistant to conventional antibiotics.
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Pereira Francisco Sávio Gomes
2018-01-01
Full Text Available This study describes properties of biomasses of Moringa oleifera Lamarck for energetic applications of production of biodiesel and briquettes. The seeds collected of the mature pods were the initial biomasses used of this plant. The seeds were separated into husks and oilseed grains, from which the oils were extracted by mechanical pressing and by solvent extraction. The crude oil mixed (of pressing and by solvent was degummed, neutralized, washed, dried and characterized. The purified oil was converted into methyl biodiesel in homogeneous alkaline transesterification, which was purified and characterized. The residual peels and pies had their calorific powers measured and compared with classic agricultural residues: firewood, sugarcane bagasse and coconut husks. Moringa culture was compared to soybeans in agricultural and biodiesel production perspectives. The analytical results show that the biomasses of the moringa are favorable as renewable biofuels like biodiesel or briquettes due to the good calorific power and simple and accessible productive technology. The production of briquettes starting from the biomasses of the moringa would be recommended with the uses of the pod husks, seed peels and pies (cakes of extraction of the oil. The agricultural management and the simple productive technologies applied to the moringa are favorable for social inclusion by enabling family agriculture.
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Klinbunga, S; Khamnamtong, B; Puanglarp, N; Jarayabhand, P; Yoosukh, W; Menasveta, P
2005-01-01
Genetic diversity of oysters Crassostrea belcheri (Sowerby, 1871), C. iredalei (Faustino, 1932), Saccostrea cucullata (Born, 1778), S. forskali (Gmelin, 1791), and Striostrea (Parastriostrea) mytiloides (Lamarck, 1819) (Ostreoida, Mollusca) was analyzed by polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP) of 16S ribosomal DNA with AcsI, AluI, DdeI, DraI, RsaI, and TaqI, 18S ribosomal DNA with HinfI, and cytochrome oxidase subunit I with AcsI, DdeI and MboI. A total of 54 composite haplotypes were observed. Species-diagnostic markers were specifically found in C. belcheri, C. iredalei, and S. cucullata, but not in S. forskali and Striostrea mytiloides, which shared common composite haplotypes. Neighbor-joining trees constructed from genetic distances between pairs of composite haplotypes and species indicated large genetic differences between Crassostrea and Saccostrea (including Striostrea mytiloides), but closer relationships were observed within each genus. Four groups of unidentified oysters (Crassostrea sp. and Saccostrea sp. groups 1, 2, and 3) were also genetically analyzed. Fixed RFLP markers were found in Crassostrea sp. and Saccostrea sp. group 2, but not in Saccostrea sp. groups 1 and 3. Phylogenetic and genetic heterogeneity analyses indicated that Crassostrea sp. and Saccostrea sp. group 2 should be considered as newly unidentified oyster species in Thailand.
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Carbon Stocks in the Small Estuarine Mangroves of Geza and Mtimbwani, Tanga, Tanzania
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Edmond Alavaisha
2016-01-01
Full Text Available Mangrove forests offer important ecosystem services, including their high capacity for carbon sequestration and stocking. However, they face rapid degradation and loss of ecological resilience particularly at local scales due to human pressure. We conducted inventory of mangrove forests to characterise forest stand structure and estimate carbon stocks in the small estuarine mangroves of Geza and Mtimbwani in Tanga, Tanzania. Forest structure, above-ground carbon (AGC, and below-ground carbon (BGC were characterised. Soil carbon was estimated to 1 m depth using loss on ignition procedure. Six common mangrove species were identified dominated by Avicennia marina (Forsk. Vierh. and Rhizophora mucronata Lamarck. Forest stand density and basal area were 1740 stems ha−1 and 17.2 m2 ha−1 for Geza and 2334 stems ha−1 and 30.3 m2 ha−1 for Mtimbwani. Total ecosystem carbon stocks were 414.6 Mg C ha−1 for Geza and 684.9 Mg C ha−1 for Mtimbwani. Soil carbon contributed over 65% of these stocks, decreasing with depth. Mid zones of the mangrove stands had highest carbon stocks. These data demonstrate that studied mangroves are potential for carbon projects and provide the baseline for monitoring, reporting, and verification (MRV to support the projects.
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Luis Felipe Skinner
2011-12-01
Full Text Available Cabo Frio, with its unique oceanographic conditions, is an important biogeographical transitional region between tropical and sub-tropical waters. This is due to the presence of upwelling from the Central Water of the South Atlantic (CWSA, and the presence of tropical waters from the Brazilian Current (BC and Coastal Water (CW. The intertidal barnacle, Tetraclita stalactifera, and its brooding stages were analyzed to correlate environmental conditions with reproductive development. Two thermal contrasting sites were chosen: Ponta da Cabeça (PC, which is under the influence of seasonal upwelling, and Ponta da Fortaleza (PF which experiences tropical influences. At each site, T. stalactifera specimens were collected monthly and their egg lamellae conditions classified into stages from 0 (empty to IV (ready to release. Our results show a seasonal effect on brooding at the PC site and a continuous development at the PF site. Nauplii larval availability also followed this trend. Differences between the sites could be due to ecological differences related to water temperature and the ecological-physiological response of the barnacles to these differences.Cabo Frio, devido suas características oceanográficas, causado pela é uma importante região biogeográfica transicional entre águas tropicais e sub-tropicais. Isto é ressurgência da Água Central do Atlântico Sul (ACAS e a presença de águas tropicais da Corrente do Brasil (CB e de Água Costeira (AC. A craca do mediolitoral Tetraclita stalactifera e seus estágios de maturação larval foram analisados a fim de serem correlacionados às condições ambientais. Dois locais com características termais contrastantes foram escolhidos: a Ponta da Cabeça (PC, que está sobre influência sazonal da ressurgência e a Ponta da Fortaleza (PF, sob influência da água tropical. Em cada local, indivíduos de T. stalactifera foram coletados mensalmente e a condição de suas lamellas ovígeras aferida e classificada desde o estágio 0 (vazio até o IV (prestes a liberar. Nossos resultados amostram um efeito sazonal na PC, enquanto no local PF foi identificado um desenvolvimento contínuo. A disponibilidade de larvas náuplios também segue esta tendência. As diferenças observadas entre os locais podem ser explicadas pelas diferenças na temperatura da água e as respostas eco-fisiológicas exibidas por T. stalactifera na região.
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González-Fernández, Carmen; Albentosa, Marina; Sokolova, Inna
2017-10-01
Marine bivalves including mussels Mytilus galloprovincialis are commonly used as sentinels for pollution monitoring and ecosystem health assessment in the coastal zones. Use of biomarkers to assess the pollution effects assumes that the effects of pollutants on the biomarkers exceed the natural background variability; yet this assumption has rarely been tested. We exposed mussels at different reproductive stages and nutritive states to two concentrations of a polycyclic aromatic hydrocarbon (fluoranthene, 3 and 60 μg L -1 ) for three weeks. Expression levels of the molecular biomarkers related to the detoxification and general stress response [cytochrome P450 oxidase (CYP450), glutathione S-transferases (GST-α; GST-S1; GST-S2), the multixenobiotic resistance protein P-glycoprotein (PgP), metallothioneins (MT10 and MT20), heat shock proteins (HSP22, HSP70-2; HSP70-3; HSP70-4), as well as mRNA expression of two reproduction-related genes, vitellogenin (Vitel) and vitelline coat lysin M7 (VCLM7)] were measured. The mussels' nutrition and reproductive state affected the baseline mRNA levels of molecular biomarkers and modulated the transcriptional responses of biomarker genes to the pollutant exposure. Thus, mussel physiological state could act as a confounding factor in the evaluation of the response of pollution through molecular biomarkers. The biomarker baseline levels must be determined across a range of physiological states to enable the use of biomarkers in monitoring programs. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Kearn, Graham; Karlsbakk, Egil; Evans-Gowing, Richard; Gerasev, Pavel
2015-09-01
A previously undescribed species of Entobdella is reported from the skin of the Greenland halibut, Reinhardtius hippoglossoides (Pleuronectiformes, Pleuronectidae). Entobdella whittingtoni sp. nov. differs from other species of Entobdella, including skin parasites of the related pleuronectids Hippoglossus hippoglossus (Atlantic halibut) and H. stenolepis (Pacific halibut), in lacking papillae on the ventral surface of the haptor. Other characteristics of E. whittingtoni are as follows: the absence of vitelline follicles lateral to the pharynx thereby exposing gut caeca in this region of whole mounts; the presence of a circular feature of unknown function, resembling a rosette in sections, attached to the wall of the internal male accessory reservoir; the lack of eyes. Papillae are also absent from the ventral surface of the haptor of the gill-parasitic entobdelline Branchobdella pugetensis, a gill parasite of the pleuronectid Atheresthes stomias. This raises the question as to whether this gill parasite has evolved from a skin-parasitic ancestor similar to E. whittingtoni. An answer to this question requires a more detailed study of the male reproductive apparatus of B. pugetensis and the use of molecular techniques to explore the relationship between B. pugetensis and E. whittingtoni.
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Sun, Lina; Sun, Jingchun; Li, Xiaoni; Zhang, Libin; Yang, Hongsheng; Wang, Qing
2017-06-01
The sea cucumber, as a member of the Echinodermata, has the capacity to restore damaged organs and body parts, which has always been a key scientific issue. MicroRNAs (miRNAs), a class of short noncoding RNAs, play important roles in regulating gene expression. In the present study, we applied high-throughput sequencing to investigate alterations of miRNA expression in regenerative intestine compared to normal intestine. A total of 73 differentially expressed miRNAs were obtained, including 59 up-regulated miRNAs and 14 down-regulated miRNAs. Among these molecules, Aja-miR-1715-5p, Aja-miR-153, Aja-miR-252a, Aja-miR-153-5p, Aja-miR-252b, Aja-miR-2001, Aja-miR-64d-3p, and Aja-miR-252-5p were differentially expressed over 10-fold at 3days post-evisceration (dpe). Notably, real-time PCR revealed that Aja-miR-1715-5p was up-regulated 1390-fold at 3dpe. Moreover, putative target gene co-expression analyses, gene ontology, and pathway analyses suggest that these miRNAs play important roles in specific cellular events (cell proliferation, migration, and apoptosis), metabolic regulation, and energy redistribution. These results will provide a basis for future studies of miRNA regulation in sea cucumber regeneration. Copyright © 2017 Elsevier Inc. All rights reserved.
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M. Nazemi
2016-04-01
Full Text Available Introduction & Objective: Holothuria leucospilota, sea cucumber, is a species of the Phylum Echinodermata. Sea cucumbers have the most natural products with biological activity. In this study we investigated the antibacterial activity of aqueous and methanol extract of H. leucospilota used against gram positive and gram negative human pathogenic bacteria. Materials & Methods: 9 Samples of H. leucospilota were harvested from the Hengam Island,. The methanol extract was prepared from the powder of sea cucumber. The antibacterial activity of the extracts was determined by broth dilution methods against clinical Gram-negative bacteria to identify MIC and MBC. Results: Aqueous extract of H. leucospilota was inactive on the bacteria. Methanol extract was active on Gram-negetive bacteria; E. coli, Salmonella typhi and Serratia marcescens. But it killed only Salmonella typhi and Serratia marcescens. The MBC of H. leucospilota methanol extract was 10 mg/ml. Methanol extract was active on all Gram-positive bacteria; B. pumilus, B. cereus and S. aureus but it killed only S. aureus. The MBC of H. leucospilota methanol extract was 40 mg/ml. Conclusion: Based on our results, H. leucospilota methanol extract. can be considered as a source of novel antibiotic. Contrary to many marine organisms, sea cucumbers are active against gram-negative bacteria. (Sci J Hamadan Univ Med Sci 2016; 23 (1:75-82
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Complete mitochondrial genome sequence of the polychaete annelidPlatynereis dumerilii
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Boore, Jeffrey L.
2004-08-15
Complete mitochondrial genome sequences are now available for 126 metazoans (see Boore 1999; Mitochondrial Genomics link at http://www.jgi.doe.gov), but the taxonomic representation is highly biased. For example, 80 are from a single phylum, Chordata, and show little variation for many molecular features. Arthropoda is represented by 16 taxa, Mollusca by eight, and Echinodermata by five, with only 17 others from the remaining {approx}30 metazoan phyla. With few exceptions (see Wolstenholme 1992 and Boore 1999) these are circular DNA molecules, about 16 kb in size, and encode the same set of 37 genes. A variety of non-standard names are sometimes used for animal mitochondrial genes; see Boore (1999) for gene nomenclature and a table of synonyms. Mitochondrial genome comparisons serve as a model of genome evolution. In this system, much smaller and simpler than that of the nucleus, are all of the same factors of genome evolution, where one may find tractable the changes in tRNA structure, base composition, genetic code, gene arrangement, etc. Further, patterns of mitochondrial gene rearrangements are an exceptionally reliable indicator of phylogenetic relationships (Smith et al.1993; Boore et al. 1995; Boore, Lavrov, and Brown 1998; Boore and Brown 1998, 2000; Dowton 1999; Stechmann and Schlegel 1999; Kurabayashi and Ueshima 2000). To these ends, we are sampling further the variation among major animal groups in features of their mitochondrial genomes.
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Astley, Henry C
2012-06-01
Brittle stars (Ophiuroidea, Echinodermata) are pentaradially symmetrical echinoderms that use five multi-jointed limbs to locomote along the seafloor. Prior qualitative descriptions have claimed coordinated movements of the limbs in a manner similar to tetrapod vertebrates, but this has not been evaluated quantitatively. It is uncertain whether the ring-shaped nervous system, which lacks an anatomically defined anterior, is capable of generating rhythmic coordinated movements of multiple limbs. This study tested whether brittle stars possess distinct locomotor modes with strong inter-limb coordination as seen in limbed animals in other phyla (e.g. tetrapods and arthropods), or instead move each limb independently according to local sensory feedback. Limb tips and the body disk were digitized for 56 cycles from 13 individuals moving across sand. Despite their pentaradial anatomy, all individuals were functionally bilateral, moving along the axis of a central limb via synchronous motions of contralateral limbs (±~13% phase lag). Two locomotor modes were observed, distinguishable mainly by whether the central limb was directed forwards or backwards. Turning was accomplished without rotation of the body disk by defining a different limb as the center limb and shifting other limb identities correspondingly, and then continuing locomotion in the direction of the newly defined anterior. These observations support the hypothesis that, in spite of their radial body plan, brittle stars employ coordinated, bilaterally symmetrical locomotion.
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Ricardo M García
2012-07-01
Full Text Available Las conchas de moluscos bivalvos marinos son extremadamente diversas en sus patrones de pigmentación y riqueza de colores. Tal diversidad se debe a factores ambientales y genéticos. En bivalvos marinos adultos, individuos con coloraciones de concha poco comunes en las poblaciones silvestres suelen presentar tasas de crecimiento y supervivencia menores que aquellos con colores de concha más frecuentes. Conociendo que la variación del color de la concha en Argopecten purpuratus está bajo control genético, en este trabajo se pone a prueba la hipótesis de que los loci responsables de dicha variación pueden afectar el crecimiento, la supervivencia y la tasa de desarrollo de las larvas de esta especie. Se estimó la supervivencia y el crecimiento en progenies de cruzamientos dirigidos entre individuos de A. purpuratus con colores de concha blanco, naranja y marrón, y se verificó la existencia de diferencias en las tasas de desarrollo. El crecimiento de las larvas producidas en cruzamientos que incluyeron individuos marrones o blancos con naranja no mostraron diferencias entre sí. En cambio, las progenies producto de autofecundaciones de individuos naranja y blancos presentaron tasas de crecimiento significativamente menores que las anteriores y distintas entre sí. Las tasas de desarrollo y de supervivencia, en cambio, no mostraron diferencias entre las progenies de los distintos tipos de cruzamientos. Los resultados sugieren que los genes que controlan la variación del color en las conchas de juveniles y adultos de A. purpuratus afectarían la tasa de crecimiento de sus larvas, pero no la tasa de desarrollo ni su supervivencia.Marine bivalve mollusks are extremely diverse in shell color and pigmentation patterns. Such diversity is affected by environmental and genetic factors. Some evidences in adult marine bivalves shows that individuals with low-frequency shell colors have lower growth rates and/or higher mortalities than those with the most frequent shell colors. Knowing that Argopecten purpuratus shell color variation is under genetic control, in this work we test the hypothesis that loci that control shell color variation also affect larvae's growth rate, survival and/or development rate. Survival, growth and development rates were estimated in larvae produced in different crosses between brooders of A. purpuratus having low frequency shell colors (white or orange and "normal" (brown color. Results showed no significant differences in growth rates between larvae produced by crosses that involved brown shell parents, or orange by white parents. However, progenies of self fertilized orange and white parents showed significant differences in growth among them, and a lower growth rate than the remaining crosses. Results suggest that genes that control shell color variation in juvenile and adult A. purpuratus could affect the growth rates of their larvae, but not the development rate or survival.
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Yuan, Xiutang; Shao, Senlin; Yang, Xiaolong; Yang, Dazuo; Xu, Qinzeng; Zong, Humin; Liu, Shilin
2016-05-01
Ocean acidification (OA) caused by excessive CO2 is a potential ecological threat to marine organisms. The impacts of OA on echinoderms are well-documented, but there has been a strong bias towards sea urchins, and limited information is available on sea cucumbers. This work examined the effect of medium-term (60 days) exposure to three pH levels (pH 8.06, 7.72, and 7.41, covering present and future pH variability) on the bioenergetic responses of the sea cucumber, Apostichopus japonicus, an ecologically and economically important holothurian in Asian coasts. Results showed that the measured specific growth rate linearly decreased with decreased pH, leading to a 0.42 %·day(-1) decrease at pH 7.41 compared with that at pH 8.06. The impacts of pH on physiological energetics were variable: measured energy consumption and defecation rates linearly decreased with decreased pH, whereas maintenance energy in calculated respiration and excretion were not significantly affected. No shift in energy allocation pattern was observed in A. japonicus upon exposure to pH 7.72 compared with pH 8.06. However, a significant shift in energy budget occurred upon exposure to pH 7.41, leading to decreased energy intake and increased percentage of energy that was lost in feces, thereby resulting in a significantly lowered allocation into somatic growth. These findings indicate that adult A. japonicus is resilient to the OA scenario at the end of the twenty-first century, but further acidification may negatively influence the grazing capability and growth, thereby influencing its ecological functioning as an "ecosystem engineer" and potentially harming its culture output.
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Yamana, Yusuke; Tanaka, Hayato
2017-10-31
A new apodid sea cucumber, Chiridota impatiens sp. nov., is described from the intertidal zone of Okinawa, Japan, and C. rigida Semper, 1867 is also described from the intertidal zone of Wakayama, as new to Japan. C. impatiens sp. nov. is approximately 60-70 mm, with 12 tentacles and 4-7 pairs of digits per tentacle, red or reddish brown in living specimens. The tentacles contain curved rod ossicles, with spinous processes and many branches in C. rigida, however, in C. impatiens sp. nov., the curved rod ossicles are crescent-shaped, sometimes distally, with spinous processes and rarely a few branches on the circumference. In both species, the body wall contains flattened rod ossicles, mostly present along the longitudinal muscle and mesentery, curved rod ossicles primarily in the body wall, and wheel ossicles only in the wheel-papillae. In C. rigida, the contents of the wheel-papillae form a hemispherical sack-shaped structures, in which the teeth-side of the wheel ossicles mostly faces towards the outside of the body. In C. impatiens sp. nov., the contents of the wheel-papillae form a cord-shaped structure (present in both preserved and living specimens), in which the teeth-side of the wheel ossicles faces various directions, and that can be induced to break through the skin of the papillae if stimulated in living specimens.
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Digital Repository Service at National Institute of Oceanography (India)
Stohr, S.; Sautya, S.; Ingole, B.S.
and it is still the standard reference work on the subject. A recent census counted 319 species of ophiuroid for the Indian Ocean (Stöhr, O'Hara & Thuy, in press), about a quarter of them endemic to the region. By comparison, the same study found 831 species... of the first lateral arm plates. Up to 18 fringe spines in each interradius. Second tentacle pore slit-shaped, opening into the mouth slit, bordered by several low scales. No other tentacle scales along arm. Large round ventral spine articulation...
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Directory of Open Access Journals (Sweden)
C.C. Cabuga
2017-09-01
Full Text Available Pomacea caniculata or Golden Apple Snail (GAS existed to be a rice pest in the Philippines and in Asia. Likewise, geographic location also contributes its increasing populations thus making it invasive among freshwater habitats and rice field areas. This study was conducted in order to describe shell shape variations and sexual dimorphism among the populations of P. caniculata. A total of 180 were randomly collected in the three lakes of Esperanza, Agusan del Sur (Lake Dakong Napo, Lake Oro, and Lake Cebulan, of which each lake comprised of 60 samples (30 males and 30 females. To determine the variations and sexual dimorphism in the shell shape of golden apple snail, coordinates was administered to relative warp analysis and the resulting data were subjected to Multivariate Analysis of Variance (MANOVA, Principal Component Analysis (PCA and Canonical Variate Analysis (CVA. The results show statistically significant (P<0.05 from the appended male and female dorsal and ventral/apertural portion. While male and female spire height, body size, and shell shape opening also shows significant variations. These phenotypic distinctions could be associated with geographic isolation, predation and nutrient component of the gastropods. Thus, the importance of using geometric morphometric advances in describing sexual dimorphism in the shell shape of P. caniculata.
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Directory of Open Access Journals (Sweden)
Robério Anastacio Ferreira
2015-06-01
Full Text Available RESUMOEstudos relacionados à morfologia vegetal com espécies florestais nativas têm sido ampliados nos últimos anos, em face da sua importância sob os aspectos taxonômicos ou por serem de grande utilidade na identificação de frutos, sementes, plântulas e mudas, em laboratórios de análises de sementes, em viveiros de produção de mudas ou em estudos que avaliem a regeneração natural em ecossistemas florestais. Porém, diante da grande diversidade de espécies, ainda não é possível encontrar informações suficientes para subsidiar tais estudos e nem coleções em herbários para um grande número de espécies nativas. Assim, este trabalho foi realizado com o objetivo de caracterizar morfologicamente frutos, sementes, plântulas e mudas de pau-brasil (Caesalpinia echinata Lam. – Fabaceae, Subfamília Caesalpinioideae. Foram realizadas, inicialmente, avaliações das características morfométricas e morfológicas externas e internas dos frutos e sementes. Em seguida, foram realizadas descrições do desenvolvimento inicial de plântulas e mudas. Considerando-se as análises descritivas da espécie, as informações de frutos, sementes, plântulas e mudas podem ser empregadas com segurança em trabalhos de identificação das espécies, tanto em trabalhos de laboratórios e viveiros quanto em estudos de campo sobre a ecologia dessa espécie. Especial atenção pode ser dada ao fruto legume seco, ao embrião, à germinação epígea fanerocotiledonar e à presença de acúleos nas fases jovens (plântulas e mudas, que são importantes para a identificação da espécie. Os caracteres que são comuns a outras espécies de Fabaceae, da Subfamília Caesalpinioideae, corroboram o caráter taxonômico dos aspectos morfológicos.
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Ostreid herpesvirus in wild oysters from the Huelva coast (SW Spain).
López-Sanmartín, M; López-Fernández, J R; Cunha, M E; De la Herrán, R; Navas, J I
2016-08-09
This is the first report of ostreid herpesvirus 1 microvariant (OsHV-1 µVar) infecting natural oyster beds located in Huelva (SW Spain). The virus was detected in 3 oyster species present in the intertidal zone: Crassostrea gigas (Thunberg, 1793), C. angulata (Lamarck, 1819) and, for the first time, in Ostrea stentina Payraudeau, 1826. Oysters were identified by a specific polymerase chain reaction (PCR) and posterior restriction fragment length polymorphism (RFLP) analysis based on cytochrome oxidase I (COI) mitochondrial DNA. Results confirmed that C. angulata still remains the dominant oyster population in SW Spain despite the introduction of C. gigas for cultivation in the late 1970s, and its subsequent naturalization. C. angulata shows a higher haplotype diversity than C. gigas. OsHV-1 virus was detected by PCR with C2/C6 pair primers. Posterior RFLP analyses with the restriction enzyme MfeI were done in order to reveal the OsHV-1 µVar. Detections were confirmed by DNA sequencing, and infections were evidenced by in situ hybridization in C. gigas, C. angulata and O. stentina samples. The prevalence was similar among the 3 oyster species but varied between sampling locations, being higher in areas with greater harvesting activities. OsHV-1 µVar accounted for 93% of all OsHV-1 detected.
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[Buffon, the director of 'Jardin du Roi' in the 1700s].
Jeune, Bernard; Petersen, Hans Christian
2008-01-01
Buffon and Linné were the two greatest naturalists of the 1700s. As they were both born in 1707, their 300 anniversaries were therefore celebrated in France and Sweden. At the celebration meeting at the University of Bourgogne in Dijon - The Buffon Legacy - September 3-6, 2007, we presented the following paper: "Buffon and the longevity of species". In the present paper the life and work of Buffon is introduced on the basis of recent literature, including Jacques Roger's famous biography. Among non-biologists Buffon has nearly been forgotten, even though in the 1700s he was considered to be at the same level as the most famous French thinkers of the Enlightenment - Montesquieu, Voltaire, Rousseau and Diderot. His largest contributions were the publication of his comprehensive "Histoire naturelle" and his long and significant leadership of "Jardin du Roi", which he built up to become one of the best scientific institutions of Europe. Buffon's scientific contributions wereas overshadowed by those of Linné, as it was his classification system, which became dominant all overn Europe. Buffon's student Lamarck and later Darwin contributed by pushing Buffon in oblivion of history, even though Darwin valued him highly. However, in recent decades Buffon is experiencing a renaissance in connection with the increasing interest in biological anthropology, biogeography, ethology, and ecology, as well as on account of his modern species concept.
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Ratajeski, K.; Sisson, T.W.; Glazner, A.F.
2005-01-01
Partial melting of mafic intrusions recently emplaced into the lower crust can produce voluminous silicic magmas with isotopic ratios similar to their mafic sources. Low-temperature (825 and 850??C) partial melts synthesized at 700 MPa in biotite-hornblende gabbros from the central Sierra Nevada batholith (Sisson et al. in Contrib Mineral Petrol 148:635-661, 2005) have major-element and modeled trace-element (REE, Rb, Ba, Sr, Th, U) compositions matching those of the Cretaceous El Capitan Granite, a prominent granite and silicic granodiorite pluton in the central part of the Sierra Nevada batholith (Yosemite, CA, USA) locally mingled with coeval, isotopically similar quartz diorite through gabbro intrusions (Ratajeski et al. in Geol Soc Am Bull 113:1486-1502, 2001). These results are evidence that the El Capitan Granite, and perhaps similar intrusions in the Sierra Nevada batholith with lithospheric-mantle-like isotopic values, were extracted from LILE-enriched, hydrous (hornblende-bearing) gabbroic rocks in the Sierran lower crust. Granitic partial melts derived by this process may also be silicic end members for mixing events leading to large-volume intermediate composition Sierran plutons such as the Cretaceous Lamarck Granodiorite. Voluminous gabbroic residues of partial melting may be lost to the mantle by their conversion to garnet-pyroxene assemblages during batholithic magmatic crustal thickening. ?? Springer-Verlag 2005.
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Directory of Open Access Journals (Sweden)
Sandra Ludwig
2011-08-01
Full Text Available Among oysters, species of Crassostrea (Sacco, 1897 are the most attractive to aquaculture. In Brazil, the genus is represented by C. rhizophorae (Guilding, 1828 and C. brasiliana (Lamarck, 1819. Because the maturation and breeding technology is not well developed for these species, aquaculturists need a reliable method to decide the correct time to place spat collectors in the field, and to identify both species, which are morphologically similar. In this study a specific Multiplex PCR protocol was developed, using one pair of universal primers from 18S rDNA as a positive control and a pair of specific primers for each target species. The sensitivity and specificity of the protocol was evaluated. It detected C. rhizophorae DNA in low concentrations, and C. brasiliana DNA in even lower concentrations. Further, the Multiplex PCR proved efficient in detecting DNA in concentrations equivalent to that of a single larva of each species, either separated or combined, when mixed with total DNA extract of a plankton sample representing 1000 L of filtered water. Field tests confirmed the applicability of the protocol, which holds the promise to become an important tool for aquaculture or conservation programs, allowing for the continuous monitoring of the life cycle of C. brasiliana and C. rhizophorae, by detecting the right periods of larval release and settlement.
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Hemolytic and cytotoxic properties of saponin purified from Holothuria leucospilota sea cucumber.
Soltani, Mozhgan; Parivar, Kazem; Baharara, Javad; Kerachian, Mohammad Amin; Asili, Javad
2014-10-01
Holothuroids (sea cucumbers) are members of the phylum echinodermata, which produce saponins. Saponins exhibit a wide spectrum of pharmacological and biological activities. In this study, we isolated the crude saponins from the body wall of the dominant Iranian species of sea cucumber, Holothuria leucospilota (H. leucospilota). The purpose of this study was to confirm the presence of saponins in the Persian Gulf H. leucospilota and study the hemolytic and cytotoxic activities of these compounds. The body wall of sea cucumber was dried and powdered and the crude saponins were isolated using various solvents. The crude saponins were further purified by column chromatography using HP-20 resin. The foam test, Thin Layer Chromatography (TLC), hemolytic assay, and Fourier Transform Infrared Spectroscopy (FTIR) confirmed the presence of saponins. Cytotoxicity was analyzed using a 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay on A549 cells, a human lung cancer cell line. The foam test, hemolytic assay, and TLC supported the presence of saponin compounds in the 80% ethanol fraction of H. leucospilota. The infrared (IR) spectrum of the extract showed hydroxyl (-OH), alkyl (C-H), ether (C-O) and ester (-C=O) absorption characteristic of teriterpenoid saponins. The C-O-C absorption indicated glycoside linkages to the sapogenins. The crude saponin extracted from sea cucumber was cytotoxic to A549 cells. The 80% ethanol fraction of saponin isolated from H. leucospilota exhibited hemolytic activity and offers promise as an anti-cancer candidate.
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Seasonal and spatial changes of macrobenthic community structure and diversity in South Yellow Sea
Li, X.; Xu, Y.
2016-02-01
The seasonal and spatial characteristics of macrobenthic community in South Yellow Sea were studied based on the data from three voyages carried out in spring, summer and autumn, 2012. A total of 218 species were obtained, including 80 species of Polychaeta, 75 of Crustacea, 35 of Mollusca, 15 of Echinodermata and 13 of other groups. Mean abundance varied from 151.4 ind./m2 in spring to 188 ind./m2 in autumn showing an increasing trend with season and mean biomass ranged from 12.1 g/m2 in spring to 33.4 g/m2 in summer. Mean secondary productivity varied from 2.5 g(AFDW)/(m2·a) in spring to 5.7 g(AFDW)/(m2·a) in summer. Two-way ANOVA indicated that biomass were significantly different among seasons and number of species and Shannon-Weiner index had significant differences among stations. But abundance, Pielou's evenness index and average taxonomic distinctness were not significantly different among either seasons or stations. Non-parametric Kruskal-Wallis test showed significant differences of secondary productivity among tations. Two-way crossed ANOSIM indicated overall significant differences of community structure among both seasons and stations. The stations were divided into four groups in spring and five in summer and autumn through the CLUSTER and nMDS analysis. Depth was an important factor influencing distribution of macrobenthos in the South Yellow Sea.
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Faunistic assemblages of a sublittoral coarse sand habitat of the northwestern Mediterranean
Directory of Open Access Journals (Sweden)
Eva Pubill
2011-02-01
Full Text Available The sublittoral megabenthic assemblages of a northwestern Mediterranean coarse sandy beach exploited for the bivalve Callista chione were studied. The spatial and bathymetric variability of its distinctive faunal assemblages was characterised by quantitative sampling performed with a clam dredge. The taxa studied were Mollusca Bivalvia and Gastropoda, Crustacea Decapoda, Echinodermata and Pisces, which accounted for over 99% of the total biomass. Three well-differentiated species assemblages were identified: (1 assemblage MSS (Medium Sand Shallow in medium sand (D50=0.37 mm and shallow waters (mean depth =6.5 m, (2 assemblage CSS (Coarse Sand Shallow in coarse sand (D50=0.62 mm in shallow waters (mean depth =6.7 m, and (3 assemblage CSD (Coarse Sand Deep in coarse sand (D50=0.64 mm in deeper waters (mean depth =16.2 m. Assemblage MSS was characterised by the codominance of the bivalves Mactra stultorum and Acanthocardia tuberculata. C. chione was dominant in both density and biomass in assemblages CSS and CSD. The occurrence of the crab Thia scutellata also characterised assemblage CSS, whereas the occurrence of the sea urchin Echinocardium mediterraneum characterised assemblage CSD. A depth breaking point of around 10 m determined the discontinuity between assemblages CSS and CSD, which was related to the closure depth of the beaches in the study area. Species richness was highest in the coarse sand communities; however, Shannon-Wiener diversity and Pielou equitability indexes were higher in the shallow fine sand community.
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Directory of Open Access Journals (Sweden)
H. BAZAIRI
2013-10-01
Full Text Available The presence of marine alien species in El-Kouf National Park and the neighbouring areas was assessed using a compilation of available information and observations, a field survey conducted on October 2010 in the framework of the MedMPAnet project and results of further monitoring during June and September 2012. A total of 9 alien species were reported: the Rhodophyta Asparagopsis taxiformis (Delile Trevisan de Saint-Léon, the Chlorophyta Caulerpa racemosa var. cylindracea (Sonder Verlaque, Huisman & Boudouresque, the crab Percnon gibbesi (H. Milne-Edwards, 1853 and the fishes Fistularia commersonii Rüppell, 1838, Siganus luridus (Rüppell, 1829, Siganus rivulatus Forsskål, 1775, Pempheris vanicolensis Cuvier, 1831, Lagocephalus sceleratus (Gmelin, 1789 and Sphyraena flavicauda Rüppell, 1838. Several of them were until now unknown for the National Park. The list of alien marine species of Libya is updated and discussed. Until now 63 marine aliens species were recorded along the Libyan coasts. These include 3 Foraminifera, 3 Ochrophyta, 5 Rhodophyta, 5 Chlorophyta, 1 Magnoliophyta, 11 Arthropoda, 13 Mollusca, 1 Echinodermata and 21 Chordata. Among these Non Indigenous Species, 43 are known as established along the Libyan coast including 8 invasive, 11 casual, 6 questionable, 3 cryptogenic and 1 unknown. An in-depth study of the marine organisms would substantially increase the number of alien species occurring in Libya. Monitoring of marine assemblages of MPAs is a valuable opportunity to go further into the knowledge of native and introduced species.
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Calero, Belén; Ramos, Ana; Ramil, Fran
2018-01-01
Ophiuroidea constitutes the largest class of the phylum Echinodermata. It includes families with suspension-feeder behaviour that can be found in dense aggregations in all oceans worldwide. Ophiothrix maculata was known as a rare suspension-feeder brittle star, with only four records in the Eastern Central Atlantic dating from almost 100 years ago. During the ten multidisciplinary Spanish and Norwegian surveys carried out from 2004 to 2012 off Northwest Africa, between the Gibraltar Strait and the Sierra Leone border from 19 to 1888 m depth, we sampled 1298 stations. We gathered about one million individuals and 124 kg of brittle stars at 501 of the stations. Eight hundred and thirty-two specimens of Ophiothrix maculata were collected at six localities on the continental slope off Mauritania, Western Sahara and Guinea Bissau, at depths between 155 and 594 m. The Guinea Bissau samples represent the southernmost current record for the species. Even though Ophiothrix maculata has been previously recorded only in isolation, we discovered dense concentrations on the Mauritanian slope on the Wolof's Seamount (580 individuals) and off the Western Sahara, in a Lophelia pertusa reef (202 individuals). In this paper, we describe these findings and discuss the association of this species to hard-bottom habitats and high primary production areas, outside of the oxygen minimum zone (OMZ). We also analyse what other factors may explain the patchy distribution of O. maculata on the Northwest African slope.
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Sarmiento-Vizcaíno, Aida; González, Verónica; Braña, Alfredo F; Palacios, Juan J; Otero, Luis; Fernández, Jonathan; Molina, Axayacatl; Kulik, Andreas; Vázquez, Fernando; Acuña, José L; García, Luis A; Blanco, Gloria
2017-02-01
Marine Actinobacteria are emerging as an unexplored source for natural product discovery. Eighty-seven deep-sea coral reef invertebrates were collected during an oceanographic expedition at the submarine Avilés Canyon (Asturias, Spain) in a range of 1500 to 4700 m depth. From these, 18 cultivable bioactive Actinobacteria were isolated, mainly from corals, phylum Cnidaria, and some specimens of phyla Echinodermata, Porifera, Annelida, Arthropoda, Mollusca and Sipuncula. As determined by 16S rRNA sequencing and phylogenetic analyses, all isolates belong to the phylum Actinobacteria, mainly to the Streptomyces genus and also to Micromonospora, Pseudonocardia and Myceligenerans. Production of bioactive compounds of pharmacological interest was investigated by high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS) techniques and subsequent database comparison. Results reveal that deep-sea isolated Actinobacteria display a wide repertoire of secondary metabolite production with a high chemical diversity. Most identified products (both diffusible and volatiles) are known by their contrasted antibiotic or antitumor activities. Bioassays with ethyl acetate extracts from isolates displayed strong antibiotic activities against a panel of important resistant clinical pathogens, including Gram-positive and Gram-negative bacteria, as well as fungi, all of them isolated at two main hospitals (HUCA and Cabueñes) from the same geographical region. The identity of the active extracts components of these producing Actinobacteria is currently being investigated, given its potential for the discovery of pharmaceuticals and other products of biotechnological interest.
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Stevenson, Angela; Davies, Jaime S.; Williams, Alan; Althaus, Franziska; Rowden, Ashley A.; Bowden, David A.; Clark, Malcolm R.; Mitchell, Fraser J. G.
2018-03-01
Patterns of habitat use by animals and knowledge of the environmental factors affecting these spatial patterns are important for understanding the structure and dynamics of ecological communities. Both aspects are poorly known for deep-sea habitats. The present study investigates echinoid distributions within cold water coral (CWC) habitats on continental margins off France, Australia, and New Zealand. It further examines the influence of habitat-related variables that might help explain the observed distribution of echinoid taxa. Six echinoid taxa were examined from video and photographic transects to reveal taxon-specific distribution patterns and habitat-related influences. The Echinoidea were found in all habitats studied, but tended to aggregate in architecturally complex habitats associated with living cold-water corals. However, a taxon-specific investigation found that such associations were largely an artefact of the dominant taxa observed in a specific region. Despite the food and shelter resources offered to echinoids by matrix-forming coral habitats, not all taxa were associated with these habitats, and some had a random association with the habitats examined, while others displayed non-random associations. Echinoid distribution was correlated with several variables; the presence of other echinoids, depth, and fishing history were the most influential factors. This study indicates that image data can be a useful tool to detect trends in echinoid habitat associations. It also suggests that refinement of the methods, in particular with studies conducted at a more precise taxon and habitat scale, would facilitate better quantitative analyses of habitat associations and paint a more realistic picture of a population's ecology. Most deep-sea ecological studies to date have been conducted at a relatively coarse taxonomic and habitat resolution, and lack sufficient resolution to provide useful information for the conservation of vulnerable deep-sea habitats.
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Diet of Norwegian coastal cod (Gadus morhua) studied by using citizen science
Enoksen, Siri Elise; Reiss, Henning
2018-04-01
The Norwegian coastal cod (Gadus morhua) is a keystone species in the food web of northern Norwegian fjords. Their relatively stationary populations might specifically depend on local food resources, but the diet of cod has rarely been studied in fjord systems. Using a citizen science approach, where recreational anglers and tourists participated in the sampling, we studied small-scale differences in the diet composition of cod in a fjord system in northern Norway. We compared the cod diet from the MPA Saltstraumen, characterised by strong tidal currents and a highly diverse and abundant fauna, with the inner fjord area of Skjerstadfjord. The diet composition of cod significantly differed between both areas within the fjord. Although fish was the dominant prey in both areas, cod consumed > 40% invertebrates in terms of weight, even in the cod size class of 70-99 cm. The invertebrate prey also caused the observed spatial differences. In Saltstraumen, brittle stars (Ophiuroidea), crabs (Brachyura) and sea cucumbers (Holothuroidea) were important food sources for cod, while sea urchins (Echinoidea), clams (Bivalvia), shrimps (Caridea) and krill (Euphausiacea) dominated the diet in the inner Skjerstadfjord. The high densities of sessile fauna in the dynamic environment of Saltstraumen, was only partly reflected in the diet of cod, with only Holothuroidea found in 17% of the stomachs. High rates of empty stomachs (24%), cannibalism as well as a higher proportion of low-energy prey in the diet of large cod, may indicate a shortage of high quality food in Skjerstadfjord. The samples for this study were collected through a citizen science campaign. This approach might provide opportunities to be used for coastal ecological monitoring with potential applications in local ecosystem management strategies through public involvement.
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Mao, Chai-An; Agca, Cavit; Mocko-Strand, Julie A; Wang, Jing; Ullrich-Lüter, Esther; Pan, Ping; Wang, Steven W; Arnone, Maria Ina; Frishman, Laura J; Klein, William H
2016-03-16
Pou domain transcription factor Pou4f2 is essential for the development of retinal ganglion cells (RGCs) in the vertebrate retina. A distant orthologue of Pou4f2 exists in the genome of the sea urchin (class Echinoidea) Strongylocentrotus purpuratus (SpPou4f1/2), yet the photosensory structure of sea urchins is strikingly different from that of the mammalian retina. Sea urchins have no obvious eyes, but have photoreceptors clustered around their tube feet disc. The mechanisms that are associated with the development and function of photoreception in sea urchins are largely unexplored. As an initial approach to better understand the sea urchin photosensory structure and relate it to the mammalian retina, we asked whether SpPou4f1/2 could support RGC development in the absence of Pou4f2. To answer this question, we replaced genomic Pou4f2 with an SpPou4f1/2 cDNA. In Pou4f2-null mice, retinas expressing SpPou4f1/2 were outwardly identical to those of wild-type mice. SpPou4f1/2 retinas exhibited dark-adapted electroretinogram scotopic threshold responses, indicating functionally active RGCs. During retinal development, SpPou4f1/2 activated RGC-specific genes and in S. purpuratus, SpPou4f2 was expressed in photoreceptor cells of tube feet in a pattern distinct from Opsin4 and Pax6. Our results suggest that SpPou4f1/2 and Pou4f2 share conserved components of a gene network for photosensory development and they maintain their conserved intrinsic functions despite vast morphological differences in mouse and sea urchin photosensory structures. © 2016 The Authors.
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International Nuclear Information System (INIS)
Sohtome, Tadahiro; Wada, Toshihiro; Mizuno, Takuji; Nemoto, Yoshiharu; Igarashi, Satoshi; Nishimune, Atsushi; Aono, Tatsuo; Ito, Yukari; Kanda, Jota; Ishimaru, Takashi
2014-01-01
Radioactive cesium ( 134 Cs and 137 Cs) concentrations in invertebrates of benthic food web (10 taxonomic classes with 46 identified families) collected from wide areas off Fukushima Prefecture (3–500 m depth) were inspected from July 2011, four months after the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident, to August 2013 to elucidate time-series trends among taxa and areas. Cesium-137 was detected in seven classes (77% of 592 specimens). Higher 137 Cs concentrations within detected data were often found in areas near or south of the FDNPP, which is consistent with the reported spatial distribution of 137 Cs concentrations in highly contaminated seawater and sediments after the FDNPP accident. Overall 137 Cs concentrations in invertebrates, the maxima of which (290 Bq kg −1 -wet in the sea urchin Glyptocidaris crenularis) were lower than in many demersal fishes, had decreased exponentially with time, and exhibited taxon-specific decreasing trends. Concentrations in Bivalvia and Gastropoda decreased clearly with respective ecological half-lives of 188 d and 102 d. In contrast, decreasing trends in Malacostraca and Polychaeta were more gradual, with longer respective ecological half-lives of 208 d and 487 d. Echinoidea showed no consistent trend, presumably because of effects of contaminated sediments taken into their digestive tract. Comparison of 137 Cs concentrations in the invertebrates and those in seawater and sediments suggest that contaminated sediments are the major source of continuing contamination in benthic invertebrates, especially in Malacostraca and Polychaeta. - Highlights: • Radioactive cesium was measured in benthic invertebrates collected off Fukushima. • Results show taxon-specific and area-specific decreases in ecological half-lives. • Reasonable depuration of 137 Cs concentration was found in Bivalvia and Gastropoda. • Slow depuration was observed in Polychaeta and Malacostraca. • Sediments are expected to be the major
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Mg and Sr in Arctic echinoderm calcite: Nature or nurture?
Iglikowska, A.; Borszcz, T.; Drewnik, A.; Grabowska, M.; Humphreys-Williams, E.; Kędra, M.; Krzemińska, M.; Piwoni-Piórewicz, A.; Kukliński, P.
2018-04-01
The Mg/Ca and Sr/Ca ratios in echinoderm skeletal calcite are used as a proxy for Phanerozoic seawater changes, since the skeletal concentrations are, to some extent, controlled by environmental factors. However, it remains unclear how the influence of environmental factors is modified by vital effects, especially in polar waters. Therefore, the goal of this study was to compare the ratios of Mg/Ca and Sr/Ca among the skeletal parts of 10 common Arctic echinoderm species belonging to three classes Echinoidea, Asteroidea and Ophiuroidea that contribute substantially to the carbon cycle in the Arctic benthic system. Significant differences were recorded in echinoid skeletal element concentrations among specific skeletal parts. The lowest Mg/Ca and Sr/Ca ratios were detected in the spines (mean Mg/Ca 37.5 ± 8.8 SD; Sr/Ca 1.8 ± 0.1). The components of the Aristotle's lantern (epiphyses, pyramids and rotulas) were characterised by the highest Mg levels (Mg/Ca 79.9 ± 6.0; 75.2 ± 9.1; 60.1 ± 3.8, respectively). It is likely that mouth parts experience greater mechanical pressure compared to other body parts, and the higher content of Mg in the Aristotle's lantern contributes to its robustness. We did not find any distinctive trends in the distribution of skeletal elements in the asteroid and ophiuroid skeletal parts. The heterogeneous concentrations of Mg and Sr in different skeleton parts of the echinoids suggest possible physiological regulation of the chemical composition rather than the composition only being influenced by the environment. We cannot recommend echinoderm skeletons as reliable indicators in palaeoenvironmental reconstructions due to the possible biological control of skeletal chemistry, which may interfere with the effect of environmental variables.
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Directory of Open Access Journals (Sweden)
L. GOREN
2017-03-01
Full Text Available The Indo-Pacific scaleworm Iphione muricata was observed and caught in the Mediterranean Sea along the coast of Israel. Morphological and molecular diagnostic characters of the species are discussed. This is the first record of this alien species in the Mediterranean Sea, and its previous reports in the Suez Canal suggest its introduction via Lessepsian migration.
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Ranger, Christopher M; Johnson-Cicalese, Jennifer; Polavarapu, Sridhar; Vorsa, Nicholi
2006-08-01
Host acceptance and population parameters of the aphid Illinoia pepperi (MacGillivray) (Hemiptera: Aphididae) were measured on highbush blueberry, Vaccinium corymbosum L. 'Elliott', and the wild species Vaccinium boreale Hall and Aalders, Vaccinium tenellum Aiton, Vaccinium pallidum Aiton, Vaccinium hirsutum Buckley, Vaccinium myrsinites Lamarck, and Vaccinium darrowi Camp. After 24 h of exposure, significantly fewer aphids remained in contact with V. boreale and V. hirsutum compared with V. corymbosum Elliott, V. darrowi, and V. pallidum. Length of the prereproductive period of I. pepperi was significantly longer on V. boreale and V. myrsinites, in contrast to V. corymbosum. Fecundity was also lower on V. boreale, V. hirsutum, V. myrsinites, and V. darrowi. Survivorship of I. pepperi 42 d after birth was significantly lower on V. hirsutum compared with the remaining Vaccinium spp. Reduced I. pepperi performance resulted in significantly lower intrinsic rate of increase (r(m)) values being associated with V. myrsinites, V. boreale, V. hirsutum, and V. darrowi, compared with V. corymbosum. Net reproductive rate (R(o)), generation time (T), and doubling time (T(d)) of I. pepperi also were affected by the Vaccinium spp. Total phenolic and flavonol content varied between Vaccinium spp., with some high phenolic content Vaccinium spp. having reduced aphid performance. However, no significant correlation between phenolics and I. pepperi performance was detected. Results from this study identified several potential sources of aphid resistance traits in wild Vaccinium spp.
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EL ORIGEN DE LAS ESPECIES Y SU RELACION CON EL INICIO DE LA ACTUAL TEORIA DE LA HERENCIA.
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William Usanquén
2009-10-01
Full Text Available En los 200 años del nacimiento de Charles Darwin se ha realizado un sinfín de discusiones y se han publicado cientos de artículos por todo el mundo haciendo referencia a los aportes de “El origen de las especies” en las diferentes ramas de la cultura occidental, Sin embargo, haciendo un mayor énfasis en las obras, como producto madurado de la mente humana, en este año más que ser el aniversario número doscientos del nacimiento de Darwin, es el 200 aniversario de la aparición de una obra fundamental dentro de la teoría biológica: La “Philosophie Zoologique” escrita por Jean-Baptiste Lamarck. Por otra parte, también celebramos los 150 años de la primera edicion de “The Origin of species by means of natural selection, or the preservation of favoured races in the struggle for life”. En la primera parte se mostraran algunos elementos históricos relacionados con la filosofía zoológica y el contexto político de su nacimiento. Posteriormente se revisaran los principales conceptos darwinianos relacionados con la herencia y sus consecuencias en la formación de la disciplina llamada genética, se estudiara el caso especial de Gregor Mendel y finalmente se mostraran las implicaciones actuales en nuestra interpretación de la teoría evolutiva.
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The shallow-water chitons (Mollusca, Polyplacophora of Caldera, Region of Atacama, northern Chile
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Juan Francisco Araya
2015-03-01
Full Text Available The Molluscan species of the northern littoral of Chile have been sparsely studied. This work reviews for the first time the diversity of polyplacophoran molluscs around the port of Caldera, in the Region of Atacama (26°45’49”S; 70°45’17”W to 27°20’23”S; 70°56’46”W, northern Chile. Eleven species were found in this study: Acanthopleura echinata (Barnes, 1824; Callistochiton pulchellus (Gray, 1828; Calloplax vivipara (Plate, 1899, Chaetopleura peruviana (Lamarck, 1819; Chiton cumingsii Frembly, 1827; Chiton granosus Frembly, 1827; Chiton magnificus Deshayes, 1827; Enoplochiton niger (Barnes, 1824, Radsia barnesii (Gray, 1828, Tonicia atrata (G. B. Sowerby II, 1840 and Tonicia chilensis (Frembly, 1827. All of the species occurring in the area have distributions in the southeastern Pacific Ocean, from Ecuador to central Chile, and three of them are species endemic to the Chilean coasts (Calloplax vivipara, Radsia barnesii, and Tonicia atrata. This diversity of species is comparable to that of better surveyed faunas of central and southern Chile or Patagonia. Of the eleven species recorded, the geographic distribution records for Callistochiton pulchellus, Radsia barnesii and Tonicia atrata are extended, and Calloplax vivipara is found alive again after 40 years, filling a gap in its known distribution. Illustrations of living specimens in their habitat, distribution records and a taxonomic key for all the studied taxa are also provided.
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E. V. Sukharenko
2017-05-01
Full Text Available Processed by-products of oil are the most common pollutants in all river and sea water. The increase in oxidative stress in bivalve molluscs was studied in both tissues of the hepatopancreas and the gill. The model for artificial treatment with processed by-products of oil was performed in a laboratory experiment with the river mollusc Dreissena polymorpha Pallas, 1771. The exposure of the molluscs over 28 days to mazut 50 mg/l induced significant increase of both final product of lipid peroxidation (LPO and antioxidant enzime activity. A significant increase in LPO was observed in the hepatopancreas and gill of D. polymorpha treated with mazut compared to the control group. Antioxidant enzyme activity of cartalase, supeoxide dismutase, glutathione reductase and glutathione-S-transferase showed a greater increase (by almost 1.5 times in the hepatopancreas than in the gill of D. polymorpha. A similar LPO growth and modulation of antioxidant enzyme activity were determined in the hepatopancreas and gill of the mussel Mytilus galloprovincialis Lamarck, 1879 collected in an area polluted with resins, hydrocarbons and asphaltenes, Donuzlav lake in the Kerch gulf. Varied cellular reactivation of the antioxidant enzyme system in the hepatopancreas rather than the gill was observed in both kinds of mollusc Dreissena and Mytilus. The obtained results are evidence of the higher sensitivity of the hepatopancreas cells of bivalve molluscs to organic pollutants compared to the gill cells.
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Was Samuel Butler Mainly Right About Evolution? Part I
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Murray Code
2013-07-01
Full Text Available Samuel Butler, a contemporary critic of Charles Darwin, proffered an alternative, vitalistic account of evolution. At the same time, he put into question all modern naturalistic treatments of this fundamental idea which presuppose that evolution is mainly a scientific problem. On the contrary, Butler in effect insists, this extremely vague idea calls for not an `explanation' but rather a fairly comprehensive, plausible story that helps elucidate an inherently complex idea. Butler can thus be read as outlining an anthropomorphic metaphorics that evokes a living Cosmos wherein it might be possible to do justice to the problem which Darwin left unresolved---the problem of heredity. In this picture of the Cosmos Butler links the fundamental notion of organization not to the allegedly universal and immutable `laws of nature,' as the moderns would have it, but rather to dynamically evolving relationships between only more or less stable habits. The variations in extant habits that emergence elicits are moreover the products of quasi-intelligent responses to new challenges from the environment. For Butler follows Lamarck in holding that all organisms possess powers capable of responding to felt needs and/or desires to make alterations in the habits (or instincts that characterize their modes of existence. He thus in the end effectively bequeaths to his readers a challenge to extend and amplify, if possible, his outline of a promising metaphysical imaginary that can take into account some highly unorthodox conjectures.
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JOSE MIGUEL ROJAS
2000-09-01
Full Text Available El gastrópodo Nodilittorina peruviana es un habitante común de la zona intermareal rocosa de la costa norte y centro de Chile. Las poblaciones de esta especie se caracterizan por presentar distribuciones agregadas. Por medio de mediciones de terreno y ensayos de laboratorio se evaluó la influencia de la agregación sobre las habilidades de termorregulación y conservación de agua, en individuos pertenecientes a dos localidades de la costa de Chile que presentan distintos regímenes termales (Taltal 25º 25' S; 70º 29' W y Las Cruces 33º 35' S; 71º 38' W. Los resultados indican que la influencia de la agregación sobre las habilidades termorregulatorias es dependiente de las condiciones locales. A pesar de que los individuos de ambas localidades presentaron puntos de tolerancia térmica similares, los caracoles de Taltal mostraron tasas de pérdidas de agua menores. El tamaño de las agregaciones se relacionó en forma negativa con la tasa de pérdida de agua de los individuos de ambas localidades. En el caso de Taltal se observó un límite de tolerancia menor que en Las Cruces y una relación positiva entre tamaño de la agregación y temperatura grupal. Los resultados demuestran que las condiciones ambientales locales puede ser determinante para la efectividad de los mecanismos de termorregulación.The gastropod Nodilittorina peruviana inhabit rocky intertidal of the north and center Chile. Populations of this species exhibits aggregated distributions. Through field and lab records we studied the effect of spatial distribution of snails on their thermoregulatory and water conservation efficiencies. We studied individuals from two localities of the Chilean coast with different climatic conditions (Taltal 25° 25 ` S; 70° 29 ` W and Las Cruces 33° 35 ` S; 71° 38 ` W. Results indicate that the influence of spatial distribution thermoregulatory efficiency is dependent of the local conditions. Although individuals from both localities presented similar thermal tolerances, snails from Taltal showed lower rates of water loss. Aggregations size were negatively related with the rate of water loss in individuals from both localities. Only, individuals from Taltal decreased their limit of thermal tolerance, and exhibited a positive relationship between aggregation size and the temperature of the group. Results demonstrated that the local environmental conditions are determinate thermoregulatory strategies.
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Mjobo, Sifiso; Thandar, Ahmed S
2016-11-09
A new genus Hemiocnus is here erected to accommodate the Mediterranean dendrochirotid sea cucumber Cladodactyla syracusana Grube, currently classified, with some doubt, in the cucumariid genus Pseudocnella. At the same time a new cucumariid species, Hemiocnus rubrobrunneus, is described from some Tunisian material, misidentified as Pseudocnella syracusana (Grube), received from the United States National Museum. The new genus appears most closely related to Pseudocnella than to any other genus within the Colochirinae. Although its body wall ossicles resemble those of Pseudocnella spp. it differs in that the two ventral-most tentacles are reduced and in the presence of rosettes in the tentacles. P. syracusana also cannot be classified in Ocnus because of the presence of multi-layered, fir-cone shaped plates in the body wall, often with one end denticulate; such ossicles are lacking in the type species of the latter genus. The new species, Hemiocnus rubrobrunneus, on the other hand, shows some resemblance to H. syracusanus in its characteristic buttons and incomplete baskets, differing in its softer body wall, lack of fir-cone-shaped plates and in the presence of rosettes and complete baskets in the body wall. There are also some resemblances of the new species to the Mediterranean species of Ocnus viz. O. brunneus, O. planci and O. lacteus, but the soft nature of the body wall, shallow quadrilocular instead of deep trilocular baskets, and the presence of large knobbed plates in the anal region precludes its inclusion in this genus.
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Aziz, Aznam; Jangoux, Michel
1985-01-01
Four new species and one new subspecies of asteroids collected by the “Siboga” Expedition in the Indo-Malayan region are described. They are deep-water species belonging to the families Goniasteridae, Solasteridae, Ganeriidae, Asteriidae and Brisingidae.
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José A Vargas
2011-03-01
Full Text Available Information on changes over time in the biodiversity and ecology of tropical systems is of increasing importance against the background of local, regional, and global dynamics. This study aimed to contribute with long-term data on the abundance fluctuations of two species of echinoderms from a tropical tidal flat. From February 1984 to December 1986, March 1985 to April 1987, and July 1994 to September 1996 (total: 76 dates, core samples (17.7cm², 15cm deep were collected at low tide at a mud-sand flat in the mid upper Gulf of Nicoya estuary, Costa Rica, as part of a survey of the benthic community. Among more than 100 taxa, the burrowing brittle star, Amphipholis geminata, and the sand dollar, Mellitella stokesii, consistently appeared in the samples over the study period. A total of 63 M. stokesii and 149 A. geminata were collected. The 43 sand dollars found during 1984-1985, give an approximate density of 35 ind./m² , which is within the range reported for this species. M. stokesii was almost absent from 1994 to 1996, while A. geminata had its peak of abundance at the end of 1995. Low abundances of the sand dollar during the rainy seasons (May-November and slight increments in dry seasons (December-April cores, also agrees with a report from the region. A. geminata also presented an irregular pattern of abundance, with slight increases at the end of the rainy seasons or during the dry seasons, when higher salinities are more suitable for echinoderms. The patchy spatial distribution of both species makes difficult the detection of patterns with a corer. Nevertheless, this information is unique due to its extensive time coverage and provides a baseline for future surveys designed specifically for the study of tropical intertidal estuarine echinoderms. Rev. Biol. Trop. 59 (1: 193-198. Epub 2011 March 01.La información sobre cambios en el tiempo, en la biodiversidad y ecología de los sistemas tropicales, es de importancia creciente en el contexto de la dinámica local, regional, o global. Este estudio tuvo por objetivo el contribuir con información de largo-plazo sobre fluctuaciones en la abundancia de dos especies de equinodermos en una planicie mareal tropical. De febrero 1984 a diciembre 1986, marzo 1985 a abril 1987, y julio 1994 a septiembre 1996 (total: 76 fechas, muestras de barreno (17.7cm², 15cm de profundidad fueron recolectadas durante la marea baja en una planicie fangosa-arenosa en la región media del estuario del Golfo de Nicoya, Costa Rica, como parte de un estudio de la comunidad bentónica. Entre las más de 100 especies, la estrella frágil excavadora, Amphipholis geminata y la galleta de mar, Mellitella stokesii, aparecieron en las muestras a lo largo del estudio. Un total de 63 M. stokesii, y 149 A. geminata fueron recolectadas. Las 43 galletas de mar encontradas durante 1984-1985, dan una densidad aproximada de 35 ind./m², la que está dentro del ámbito informado para esta especie. M. stokesii estuvo casi ausente entre 1994 y 1996, mientras que A. geminata tuvo su pico de abundancia a fines de 1995. Escasa abundancia de la galleta durante la estación de lluvias (Mayo a Noviembre, y pequeños incrementos durante la estación seca (Diciembre a Abril, también están dentro de lo informado para la región. A. geminata también presentó un patrón irregular de abundancia, con pequeños incrementos durante el fin de la estación de lluvias o durante la estación seca, cuando las salinidades altas son más adecuadas para los equinodermos. La distribución agregada de ambas especies hace difícil la identificación de patrones con el barrreno. No obstante, esta información es única debido a lo amplio de la cobertura temporal, y provee una línea base para futuros muestreos diseñados específicamente para el estudio de los equinodermos estuarinos tropicales de la zona de entre-mareas.
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Martins, Luciana; Tavares, Marcos
2018-04-12
Two new species in the genera Thyone and Havelockia are described and illustrated based upon specimens collected from off the southeastern Brazilian coast. Thyone florianoi sp. nov. is characterized by having two pillared body wall tables with four-holed discs and introvert with multilocular tables. Thyone crassidisca is recorded herein for the first time from the South Atlantic Ocean (Brazil). Havelockia mansoae sp. nov. is distinctive in having two pillared body wall tables with four-holed discs and introvert with plates. This is the first record of the genus Havelockia from Brazilian waters.
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Quantification of intensive hybrid coastal reclamation for revealing its impacts on macrozoobenthos
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Yan, Jiaguo; Cui, Baoshan; Zheng, Jingjing; Xie, Tian; Wang, Qing; Li, Shanze
2015-01-01
Managing and identifying the sources of anthropogenic stress in coastal wetlands requires an in-depth understanding of relationships between species diversity and human activities. Empirical and experimental studies provide clear evidence that coastal reclamation can have profound impacts on marine organisms, but the focus of such studies is generally on comparative or laboratory research. We developed a compound intensity index (reclamation intensity index, RI) on hybrid coastal reclamation, to quantify the impacts of reclamation on coastal ecosystems. We also made use of mean annual absolute changes to a number of biotic variables (biodiversity, species richness, biomass of total macrozoobenthos, and species richness and biomass of Polychaeta, Mollusca, Crustacea, and Echinodermata) to determine Hedges’d index, which is a measure of the potential effects of coastal reclamation. Our results showed that there was significant difference of coastal reclamation intensity between Yellow Sea, East China Sea and South China Sea, the biological changes in effect sizes of the three regions differed greatly over time. Our modelling analyses showed that hybrid coastal reclamation generally had significant negative impacts on species diversity and biomass of macrozoobenthos. These relationships varied among different taxonomic groups and included both linear and nonlinear relationships. The results indicated that a high-intensity of coastal reclamation contributed to a pronounced decline in species diversity and biomass, while lower-intensity reclamation, or reclamation within certain thresholds, resulted in a small increase in species diversity and biomass. These results have important implications for biodiversity conservation and the ecological restoration of coastal wetlands in face of the intensive reclamation activities. (letter)
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Hemolytic and Cytotoxic Properties of Saponin Purified from Holothuria leucospilota Sea Cucumber
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Mozhgan Soltani
2014-10-01
Full Text Available Background: Holothuroids (sea cucumbers are members of the phylum echinodermata, which produce saponins. Saponins exhibit a wide spectrum of pharmacological and biological activities. In this study, we isolated the crude saponins from the body wall of the dominant Iranian species of sea cucumber, Holothuria leucospilota (H. leucospilota. The purpose of this study was to confirm the presence of saponins in the Persian Gulf H. leucospilota and study the hemolytic and cytotoxic activities of these compounds. Methods: The body wall of sea cucumber was dried and powdered and the crude saponins were isolated using various solvents. The crude saponins were further purified by column chromatography using HP-20 resin. The foam test, Thin Layer Chromatography (TLC, hemolytic assay, and Fourier Transform Infrared Spectroscopy (FTIR confirmed the presence of saponins. Cytotoxicity was analyzed using a 3-(4, 5-dimethylthiazol-2-yl-2, 5-diphenyltetrazolium bromide (MTT assay on A549 cells, a human lung cancer cell line. Results: The foam test, hemolytic assay, and TLC supported the presence of saponin compounds in the 80% ethanol fraction of H. leucospilota. The infrared (IR spectrum of the extract showed hydroxyl (-OH, alkyl (C-H, ether (C-O and ester (–C=O absorption characteristic of teriterpenoid saponins. The C-O-C absorption indicated glycoside linkages to the sapogenins. The crude saponin extracted from sea cucumber was cytotoxic to A549 cells. Conclusion: The 80% ethanol fraction of saponin isolated from H. leucospilota exhibited hemolytic activity and offers promise as an anti-cancer candidate.
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Maurice R Elphick
Full Text Available Peptides that cause muscle relaxation or contraction or that modulate electrically-induced muscle contraction have been discovered in the sea cucumber Apostichopus japonicus (Phylum Echinodermata; Class Holothuroidea. By analysing transcriptome sequence data, here the protein precursors of six of these myoactive peptides (the SALMFamides Sticho-MFamide-1 and -2, NGIWYamide, stichopin, GN-19 and GLRFA have been identified, providing novel insights on neuropeptide and endocrine-type signalling systems in echinoderms. The A. japonicus SALMFamide precursor comprises eight putative neuropeptides including both L-type and F-type SALMFamides, which contrasts with previous findings from the sea urchin Strongylocentrotus purpuratus where L-type and F-type SALMFamides are encoded by different genes. The NGIWYamide precursor contains five copies of NGIWYamide but, unlike other NG peptide-type neuropeptide precursors in deuterostomian invertebrates, the NGIWYamide precursor does not have a C-terminal neurophysin domain, indicating loss of this character in holothurians. NGIWYamide was originally discovered as a muscle contractant, but it also causes stiffening of mutable connective tissue in the body wall of A. japonicus, whilst holokinins (PLGYMFR and derivative peptides cause softening of the body wall. However, the mechanisms by which these peptides affect the stiffness of body wall connective tissue are unknown. Interestingly, analysis of the A. japonicus transcriptome reveals that the only protein containing the holokinin sequence PLGYMFR is an alpha-5 type collagen. This suggests that proteolysis of collagen may generate peptides (holokinins that affect body wall stiffness in sea cucumbers, providing a novel perspective on mechanisms of mutable connective tissue in echinoderms.
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Evaluation of body weight of sea cucumber Apostichopus japonicus by computer vision
Liu, Hui; Xu, Qiang; Liu, Shilin; Zhang, Libin; Yang, Hongsheng
2015-01-01
A postichopus japonicus (Holothuroidea, Echinodermata) is an ecological and economic species in East Asia. Conventional biometric monitoring method includes diving for samples and weighing above water, with highly variable in weight measurement due to variation in the quantity of water in the respiratory tree and intestinal content of this species. Recently, video survey method has been applied widely in biometric detection on underwater benthos. However, because of the high flexibility of A. japonicus body, video survey method of monitoring is less used in sea cucumber. In this study, we designed a model to evaluate the wet weight of A. japonicus, using machine vision technology combined with a support vector machine (SVM) that can be used in field surveys on the A. japonicus population. Continuous dorsal images of free-moving A. japonicus individuals in seawater were captured, which also allows for the development of images of the core body edge as well as thorn segmentation. Parameters that include body length, body breadth, perimeter and area, were extracted from the core body edge images and used in SVM regression, to predict the weight of A. japonicus and for comparison with a power model. Results indicate that the use of SVM for predicting the weight of 33 A. japonicus individuals is accurate ( R 2=0.99) and compatible with the power model ( R 2 =0.96). The image-based analysis and size-weight regression models in this study may be useful in body weight evaluation of A. japonicus in lab and field study.
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G. D'ONGHIA
2015-01-01
Full Text Available Macro- and megafauna were recorded in the submarine Bari Canyon (southern Adriatic Sea, Mediterranean Sea during an oceanographic cruise carried out in May-June 2012 and an experimental fishing survey conducted in November 2013. During the former, a total of 20 benthic samples were taken using a Van Veen grab at depths between 268 and 770 m and 4 deployments of a baited lander, for about 43 hours of video records, were carried out at depths between 443 and 788 m. During the latter, 8 longline fishing operations were conducted from 338 down to 612 m. Eighty-five living benthic and benthopelagic species were recorded: 29 Porifera, 1 Cnidaria, 2 Mollusca, 11 Annelida, 1 Arthropoda, 19 Bryozoa, 3 Echinodermata and 19 Chordata. A total of 51 species are new records for the Bari Canyon, 29 new records for the Adriatic Sea. Among the Porifera Cerbaris curvispiculifer is a new addition for the Italian Sponge Fauna. The first certain record of living specimens for the bryozoan Crisia tenella longinodata is reported. A total of 6 Mediterranean endemic species have been identified: 4 Porifera and 2 Annelida. The bathymetric range of some species has been extended. New information acquired for deep sea species confirms their importance in the structure of cold-water coral communities. This study has updated the knowledge on the biodiversity of the Adriatic Sea, as well as of the Bari Canyon in particular, one of the sites designated as “jewels of the Mediterranean” for which urgent conservation measures are needed.
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Giribet, G; Distel, D L; Polz, M; Sterrer, W; Wheeler, W C
2000-09-01
Triploblastic relationships were examined in the light of molecular and morphological evidence. Representatives for all triploblastic "phyla" (except Loricifera) were represented by both sources of phylogenetic data. The 18S ribosomal (rDNA) sequence data for 145 terminal taxa and 276 morphological characters coded for 36 supraspecific taxa were combined in a total evidence regime to determine the most consistent picture of triploblastic relationships for these data. Only triploblastic taxa are used to avoid rooting with distant outgroups, which seems to happen because of the extreme distance that separates diploblastic from triploblastic taxa according to the 18S rDNA data. Multiple phylogenetic analyses performed with variable analysis parameters yield largely inconsistent results for certain groups such as Chaetognatha, Acoela, and Nemertodermatida. A normalized incongruence length metric is used to assay the relative merit of the multiple analyses. The combined analysis having the least character incongruence yields the following scheme of relationships of four main clades: (1) Deuterostomia [((Echinodermata + Enteropneusta) (Cephalochordata (Urochordata + Vertebrata)))]; (2) Ecdysozoa [(((Priapulida + Kinorhyncha) (Nematoda + Nematomorpha)) ((Onychophora + Tardigrada) Arthropoda))]; (3) Trochozoa [((Phoronida + Brachiopoda) (Entoprocta (Nemertea (Sipuncula (Mollusca (Pogonophora (Echiura + Annelida)))))))]; and (4) Platyzoa [((Gnathostomulida (Cycliophora + Syndermata)) (Gastrotricha + Plathelminthes))]. Chaetognatha, Nemertodermatida, and Bryozoa cannot be assigned to any one of these four groups. For the first time, a data analysis recognizes a clade of acoelomates, the Platyzoa (sensu Cavalier-Smith, Biol. Rev. 73:203-266, 1998). Other relationships that corroborate some morphological analyses are the existence of a clade that groups Gnathostomulida + Syndermata (= Gnathifera), which is expanded to include the enigmatic phylum Cycliophora, as sister group
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Lourens, Lucas
2016-04-01
The astronomical theory of climate has revolutionized our understanding of past climate change and the development of highly accurate geologic time scales for the entire Cenozoic. Most of this understanding has started with the construction of high-resolution stable oxygen isotope (18O) records from planktonic and benthic foraminifera of open ocean deep marine sediments explored by the international drilling operations of DSDP, ODP and IODP. These efforts culminated into global ocean isotopic stacked records, which give a clear picture of the evolution of the climate state through time. Fundamental for these reconstructions are the assumptions made between the astronomical forcing and the tuned time series and the accuracy of the astronomical solution. In the past decades, an astronomically calibrated time scale for the Pliocene and Pleistocene of the Mediterranean has been developed, which has become the reference for the standard Geologic Time Scale. Characteristic of the studied marine sediments are the cyclic lithological alternations, reflecting the interference between obliquity and precession-paced low latitude climate variability. These interference patterns allowed to evaluate the accuracy of astronomical solutions and to constrain the dynamical ellipticity of the Earth and tidal dissipation by the Sun and the Moon, which in turn provided the backbone for the widely applied LR04 open ocean benthic isotope stack of the past 5 Myr. So far, the assumed time lags between orbital forcing and the global climate response as reflected in LR04 have not been tested, while these assumptions hark back to SPECMAP, using simple ice sheet models and a limited number of radiometric dates. In addition, LR04 adopted a shorter response time for the smaller ice caps during the Pliocene. Here I present the first benthic 18O record of the Mediterranean reference scale, which strikingly mirrors the LR04. I will use this record to discuss the assumed phase relations and its potential to constrain global sea level changes and their cause over the past 5.3 million years.
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Fossils and Theories of Evolution in Gustave Flaubert’s Bouvard et Pécuchet
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Anthony Zielonka
2011-07-01
Full Text Available Cette étude se propose d’analyser de près le chapitre III de ce chef d’œuvre comique et satirique qu’est le dernier roman de Flaubert, Bouvard et Pécuchet (1881. Après avoir exploré la médecine, la cosmologie, l’astronomie et la zoologie, les « deux bonshommes » de Flaubert se tournent vers la géologie, la paléontologie, et même les théories rivales de l’évolution. Ce chapitre est d’un intérêt considérable comme tour de force comique, surtout quand on le replace dans le contexte des découvertes, théories, controverses et querelles scientifiques (incluant les conflits entre les positions antagonistes de la religion et de la science qui faisaient rage à l’époque de Flaubert. Alors que le romancier avait réalisé des recherches exhaustives sur l’histoire des sciences, il est particulièrement intéressant de relever que ce sont les théories et les découvertes les plus récentes qui sont présentées sur le mode comique et sceptique. Après avoir passé en revue les idées de Buffon, Cuvier, Lamarck et Geoffroy Saint-Hilaire, ainsi que celle des savants fidèles à l’inspiration biblique, Bouvard et Pécuchet ne manquent pas de conclure à l’incompatibilité, et finalement à l’inanité, de toutes ces théories. Ils tirent leurs informations d’ouvrages savants mais aussi populaires, puisant dans les journaux et les magazines. Flaubert montre, de manière tout à fait significative, comment les simplifications et les erreurs des textes de vulgarisation ne servent qu’à renforcer le trouble et le doute des deux personnages et les amènent finalement à abandonner leurs recherches scientifiques.This paper proposes a close textual analysis of Chapter III of the masterpiece of comic and satirical fiction that is Gustave Flaubert’s last novel, Bouvard et Pécuchet (1881. After exploring the sciences of medicine, cosmology, astronomy, and zoology, Flaubert’s “deux bonshommes” turn their attention
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Circulating nucleic acids and evolution.
Anker, Philippe; Stroun, Maurice
2012-06-01
J.B. Lamarck in 1809 was the first to present a theory of evolution. He proposed it was due to the adaptation of species to environmental changes, this adaptation being acquired by the offspring. In 1868, Darwin suggested that cells excrete gemmules, which circulate through the body and reach the gonads where they are transmitted to the next generation. His main argument came from graft hybrids. In the fifties and sixties, Russian geneticists, rejecting neo-Darwinism, said that acquired characteristics were the basis of evolution. The main experiments on which they based their theory were the transmission of hereditary characteristics by a special technique of grafting between two varieties of plants. We repeated this kind of experiment and also succeeded in obtaining hereditary modifications of the pupil plants that acquired some characteristics of the mentor variety. Rather than adopting the views of the Russian scientists, we suggested that DNA was circulating between the mentor and pupil plants. Hirata's group have shown recently, by using molecular techniques such as cloning, RFLP PCR and sequencing some genes of their graft hybrids of pepper plants, that transfer of informative molecules from the mentor to the pupil plant does exist. Nucleic acids are actively released by cells; they circulate in the body. They can transform oncogenically or trigger antibody response but the only genetic transformation showing that DNA can go from the soma to the germen comes from graft hybrids. This suggests that circulating nucleic acids, in this case DNA, like Darwin's gemmules, play a role in the mechanism of evolution.
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Reflexos da clarificação do caldo de cana com moringa sobre compostos inorgânicos do açúcar VHP
Directory of Open Access Journals (Sweden)
Gustavo H. G. Costa
2015-02-01
Full Text Available Objetivou-se, neste trabalho, avaliar os reflexos da clarificação do caldo de cana utilizando extrato de folhas e sementes de moringa (Moringa oleifera Lamarck como auxiliares de sedimentação sobre os teores dos compostos inorgânicos do caldo clarificado e do açúcar VHP (Very High Purity - Tipo Exportação produzido. O delineamento experimental utilizado foi o fatorial 5 x 2 com quatro repetições; o primeiro fator correspondeu aos auxiliares de sedimentação: extrato de folhas e sementes de moringa, polieletrólito sintético e testemunha; já o segundo fator correspondeu a duas variedades de cana-de-açúcar: RB92579 e RB867515. O caldo extraído foi clarificado através de caleagem simples, concentrado até 60 oBrix e submetido ao processo de cozimento. No caldo original, clarificado e no açúcar produzido, foram quantificados os teores de fósforo, potássio, cálcio, sódio, magnésio, manganês e ferro além do teor de cinzas totais. Os empregos dos extratos de folhas e sementes de moringa se mostraram eficazes no tratamento do caldo destinado à produção de açúcar, por eliminar quantidades significativas de cálcio e ferro em comparação ao polieletrólito sintético. O extrato de folhas foi o melhor auxiliar de sedimentação,quando comparado aos demais.
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Who invented the dichotomous key? Richard Waller's watercolors of the herbs of Britain.
Griffing, Lawrence R
2011-12-01
On 27 March 1689, Richard Waller, Fellow and Secretary of the Royal Society presented his "Tables of the English Herbs reduced to such an order, as to find the name of them by their external figures and shapes" to his assembled colleagues at a meeting of the Royal Society. These tables were developed for the novice by being color images, composed in pencil and watercolor, of selected plants and their distinguishing characteristics. The botanical watercolors for the tables are now a Turning-the-Pages document online on the website of the Royal Society. However, for the past 320 years, the scientific context for the creation of these outstanding botanical watercolors has remained obscure. These tables were developed by Waller as an image-based dichotomous key, pre-dating by almost 100 years the text-based dichotomous keys in the first edition of Flora Française (1778) by Jean Baptiste Lamarck, who is generally given priority for the development of the dichotomous key. How these large folio images were arranged to illustrate a dichotomous key is unknown, but an arrangement based on Waller's description is illustrated here as leaf-ordering for the separate hierarchical clusters (tables). Although only 24 species of watercolored dicot herbs out of a total of 65 in the set of watercolors (the others being monocots) are used in these tables, they are a "proof of concept", serving as models upon which a method is based, that of using a key composed of dichotomous choices for aiding identification.
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International Nuclear Information System (INIS)
Beu, A.G.
2010-01-01
Three new species: Grandicrepidula hemispherica (Nukumaruan, S Hawke's Bay), Pelicaria Granttaylori (Mangapanian-early Nukumaruan, Wanganui-Hawke's Bay), Pelicaria arahura (Waipipian-early Mangapanian, Westland and Hawke's Bay). Drawings of marine species in Smith's (1874) three plates of New Zealand molluscan types are republished. Further Australian molluscs in Wanganui Basin: Sabia australis (Lamarck), Clanculus plebejus (Philippi), both early Nukumaruan. Further northern New Zealand molluscs in Wanganui Basin: Stephopoma roseum (Quoy and Gaimard), OIS 13, 9. Distinctive gastropods extinct at end Nukumaruan: Struthiolaria frazeri (Hutton), Taxonia suteri (Marwick). Taniella planisuturalis (Marwick) (Opoitian-Nukumaruan, southern NZ) and Trivia (Ellatrivia) zealandica (Kirk) (Nukumaruan, Hawke's Bay-Wanganui; Castlecliffian, North Canterbury) occur in Castlecliffian (OIS 15?) rocks at Whakatane. Cantharidella tessellate (A. Adams) and Risellopsis varia (Hutton), formerly Haweran, are recorded from Nukumaruan and Castlecliffian rocks, respectively. New fossil late Nukumaruan-early Castlecliffian records listed from Mikonui-1 offshore well, Westland, include Malluvium calcareum (Suter) and 10 other species. Other biostratigraphically useful gastropods: Calliostoma (Maurea) nukumaruense (Laws) (Mangapanian-OIS 17); Argobuccinum pustulosum (Lightfoot), Semicassis labiate (Perry) (both earliest in OIS 7). New synonymy: Zeacumantus perplexus (Marshall and Murdoch) =Z. lutulentus (Kiener); Pelicaria vermis (Martyn) =all named Nukumaruan-Recent forms (other than P. rugosa (Marwick) and P. granttaylori n. sp.); Trivia flora Marwick =T.zealandica Kirk. Taxonomy revised: Zelippistes benhami (Suter) (OIS 13 and 9 at Wanganui), distinguished from Lippistes and Separatista; Stiracolpus species, informally; Maoricrypta profunda (Hutton), Waipipian-early Castlecliffian (- OIS 19); M. radiata (Hutton) (=incurva Zittel,=hochetteriana Woods, =wilckensi Finlay), (Middle Miocene
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The Atlantic Ocean: An Impassable Barrier for the Common Octopus, Octopus vulgaris
Perez-Viscasillas, J.; Schizas, N. V.; Jassoud, A.
2016-02-01
Octopus vulgaris (Lamarck 1798) inhabits the Mediterranean, the temperate and tropical coastal waters of the Atlantic Ocean and is also present in the south Indian Ocean and Japan. We questioned the reported widespread distribution and especially the amphi-Atlantic distribution of O. vulgaris by comparing patterns of genetic variation in the Cytochrome Oxidase Subunit I (COI), the 17th intron of the Na(+)/K(+)-ATPase alpha subunit (Na/K-ATPase 17th intron), and 16S genes from several populations throughout the presumed distribution. Bayesian genealogies based on COI sequences resulted in three monophyletic lineages: a Caribbean, a Eurafrican and a Japanese one. The Eurafrican lineage is more closely related to the Japanese than to the Caribbean lineage. Within the Caribbean, the most common mitochondrial haplotype is shared by all sampled locations except for Curaçao. The most common COI haplotype in the Eurafrican group is shared by all populations. The Caribbean octopus exhibits a divergence of 11.5% compared to the Eurafrican and Japanese octopus, whereas the latter groups are 3.1% divergent. The Na/K-ATPase 17th intron data from Caribbean and Mediterranean/Atlantic Spain octopods is concordant with the mitochondrial data set, separating these two populations. The 16s data is still being analysed, but preliminary analysis supports the dual population hypothesis. The reciprocal monophyly observed with both COI and Na/K-ATPase 17th intron between the Caribbean and European O. vulgaris suggests the historical cessation of gene flow between the two sides of the Atlantic and highlights the presence of a highly differentiated Caribbean lineage.
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Faggionato, Davide; Serb, Jeanne M
2017-08-01
The rise of high-throughput RNA sequencing (RNA-seq) and de novo transcriptome assembly has had a transformative impact on how we identify and study genes in the phototransduction cascade of non-model organisms. But the advantage provided by the nearly automated annotation of RNA-seq transcriptomes may at the same time hinder the possibility for gene discovery and the discovery of new gene functions. For example, standard functional annotation based on domain homology to known protein families can only confirm group membership, not identify the emergence of new biochemical function. In this study, we show the importance of developing a strategy that circumvents the limitations of semiautomated annotation and apply this workflow to photosensitivity as a means to discover non-opsin photoreceptors. We hypothesize that non-opsin G-protein-coupled receptor (GPCR) proteins may have chromophore-binding lysines in locations that differ from opsin. Here, we provide the first case study describing non-opsin light-sensitive GPCRs based on tissue-specific RNA-seq data of the common bay scallop Argopecten irradians (Lamarck, 1819). Using a combination of sequence analysis and three-dimensional protein modeling, we identified two candidate proteins. We tested their photochemical properties and provide evidence showing that these two proteins incorporate 11-cis and/or all-trans retinal and react to light photochemically. Based on this case study, we demonstrate that there is potential for the discovery of new light-sensitive GPCRs, and we have developed a workflow that starts from RNA-seq assemblies to the discovery of new non-opsin, GPCR-based photopigments.
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Time- and depth-wise trophic niche shifts in Antarctic benthos.
Calizza, Edoardo; Careddu, Giulio; Sporta Caputi, Simona; Rossi, Loreto; Costantini, Maria Letizia
2018-01-01
Climate change is expected to affect resource-consumer interactions underlying stability in polar food webs. Polar benthic organisms have adapted to the marked seasonality characterising their habitats by concentrating foraging and reproductive activity in summer months, when inputs from sympagic and pelagic producers increase. While this enables the persistence of biodiverse food webs, the mechanisms underlying changes in resource use and nutrient transfer are poorly understood. Thus, our understanding of how temporal and spatial variations in the supply of resources may affect food web structure and functioning is limited. By means of C and N isotopic analyses of two key Antarctic benthic consumers (Adamussium colbecki, Bivalvia, and Sterechinus neumayeri, Echinoidea) and Bayesian mixing models, we describe changes in trophic niche and nutrient transfer across trophic levels associated with the long- and short-term diet and body size of specimens sampled in midsummer in both shallow and deep waters. Samplings occurred soon after the sea-ice broke up at Tethys Bay, an area characterised by extreme seasonality in sea-ice coverage and productivity in the Ross Sea. In the long term, the trophic niche was broader and variation between specimens was greater, with intermediate-size specimens generally consuming a higher number of resources than small and large specimens. The coupling of energy channels in the food web was consequently more direct than in the short term. Sediment and benthic algae were more frequently consumed in the long term, before the sea-ice broke up, while consumers specialised on sympagic algae and plankton in the short term. Regardless of the time scale, sympagic algae were more frequently consumed in shallow waters, while plankton was more frequently consumed in deep waters. Our results suggest a strong temporal relationship between resource availability and the trophic niche of benthic consumers in Antarctica. Potential climate-driven changes
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Directory of Open Access Journals (Sweden)
Gisela Geraldine Castilho Westphal
2016-03-01
Full Text Available Abstract Uncontrolled extractivism has led to a worldwide reduction in oyster stocks. The use of new and more efficient management tools for impacted environments must increase. The application of such tools requires previous biological and environmental knowledge of the resident populations of these bivalve mollusks. Technical difficulties are usually associated with studies of submerged oyster banks, and these difficulties result in a considerable lack of biological data on the oysters that inhabit subtidal zones. This study aimed to survey Crassostrea brasiliana (also known as C. gasar stocks in submerged banks and to evaluate a method with which to measure the extent of the banks and identify and quantify the oysters in the banks with the use of side-scan sonar. This study was conducted on 10 oysters banks located in the subtidal zone of Guaratuba Bay, on the south coast of Brazil. The prospection of all these banks was later validated by diving, and oyster samples (n = 20/bank were collected for species identification with a molecular method. Only one bank contained oysters that were generically classified as Crassostrea sp.; those in the remaining banks being identified as C. brasiliana. The prospected banks contained oysters of various sizes (average 1.5 m, n = 1,107 that were heterogeneously scattered in the riverbeds. The total number of oysters in the 10 sampled banks was estimated to be 21,159.13 oysters or 1 oyster/4.5 m², which represents a low oyster density in the study site. The results validate the use of side-scan sonar as an efficient means with which to prospect for oysters in banks located within subtidal zones.
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Aguirre Velarde, Arturo; Flye-Sainte-Marie, Jonathan; Mendo, Jaime; Jean, Fred
2015-05-01
We investigated the rhythm of micro-striae formation in the shell of Argopecten purpuratus and environmental influence on micro-growth increments by monitoring growth over a 98-day period between April and July 2007 under bottom and suspended culture (2 m above the bottom) rearing conditions. The transfer of individuals to the study site induced the formation of a notable growth mark that allowed us to count the number of micro-striae formed between transfer and sampling dates. Micro-striae counts showed a deposition rate of one stria per day independent of rearing condition. This result allowed us to analyse the relationships between growth increments and environmental conditions. We therefore examined the deviations between observed growth rates and growth rates predicted from a Von Bertalanffy growth function. Cross-correlation analysis revealed significant correlations, without time-lag, between these deviations and both particulate organic carbon and nitrogen concentrations in the bottom treatment. Additionally, we observed negative correlations with temperature and current speed at this depth with time-lags of 1 and 10 days respectively. In the suspended treatment, we observed a significant negative correlation with temperature, only with a 12-day lag-time. Our results show that growth response to environmental variability is not always instantaneous. This delay can be explained by the time delay over which metabolic processes need to be performed (e.g. digestion, use/movements of reserves, growth, reproduction). Further modeling studies could help to better understand these processes.
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Directory of Open Access Journals (Sweden)
Tomáš Vendl
2016-09-01
Full Text Available The third larval instar of Goliathus goliatus (Drury, 1770, G. orientalis Moser, 1909 and G. albosignatus Boheman, 1857 are described and illustrated for the first time and compared with the immature stages of other Cetoniinae. Larval development of G. goliatus is investigated under laboratory conditions, with particular emphasis on food requirements. These results support the obligatory requirement of proteins in the larval diet. The association between larval morphological traits (e. g., the shape of the mandibles and pretarsus, presence of well-developed stemmata and larval biology is discussed. Based on observations and the data from captive breeds it is concluded that a possible shift from pure saprophagy to an obligatory predaceous way of larval life occurred within the larvae of this genus, which may explain why these beetles achieve such an enormous size.
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Directory of Open Access Journals (Sweden)
Alberto Kioharu Nishida
1995-01-01
Full Text Available A survey of Mytellaguyanensis occurrence and population dynamics were performed in the Paraíba do Norte river estuary. The characterization and the influence of temperature, salinity and substrate, as well as the associated fauna and flora on the population were also examined. Mytella guyanensis lives buried in the substrate of the mangrove intertidal zone of the Paraíba do Norte river estuary, from the mouth to 24 km upriver. Average annual density of this bivalve species was 5.2 individuals per m², with a predominantly aggregated distribution. The most frequent size was between 4.5 and 5.5 cm in length. Analysis of the substrate demonstrated the presence of two types of substrates in relation to the percentage of silt and clay and the water content. Besides interfering in the population density, the substrate heterogeneity may be a decisive factor in aggregation. Eight species of crustacean decapods and one bivalve species were identified as associated fauna.A ocorrência de M, guyanensis no estuário do Rio Paraíba do Norte foi mapeada, determinando-se sua presença ao longo dos afluentes e ilhas aí existentes. O estudo da dinâmica da população foi realizado em área protegida da Ilha da Restinga, coletando-se os animais ao longo de 37 transecções. A cada mês foram feitos 60 lançamentos com um delimitador de 0,1 m², sobre uma ou mais transecções. Todo o substrato foi retirado juntamente com os exemplares de M. guyanensis e a fauna associada, até a profundidade de 10 cm. A triagem dos exemplares menores foi feita por peneiramento do substrato. O tipo de substrato foi anotado a cada lançamento. Dois tipos de substrato estão presentes na área: um substrato de tipo consistente, constituido por 89.7% de silte e argila e 10.3% de areia fina e outro de tipo não consistente contendo 74.5% de silte e argila e 25.5% de areia fina. O substrato de tipo não consistente apresenta quantidade de água significativamente maior que o de tipo consistente. Mytella guyanensis vive enterrada no solo numa profundidade máxima de 1,0 cm, sempre envolvida pelos filamentos do bisso. A densidade média anual observada para a espécie foi de 5,2 indivíduos por m²; a distribuição espacial predominante foi do tipo agregado, sofrendo interferência do tipo de substrato presente. Houve preferência de fixação da espécie pelo substrato do tipo consistente. Animais entre 4,5 e 5,5 cm de comprimento ocorrem o ano todo, sendo mais numerosos aqueles com comprimento entre 4,5 e 5,0 cm. A presença de formas jovens foi assinalada em baixa frequência em alguns meses do ano. A salinidade da água estuarina variou de acordo com o regime pluviométrico da região, permanecendo dentro dos níveis de tolerância da espécie. A fauna associada está representada por oito espécies de crustáceos e por uma de molusco bivalve.
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Capetillo, N.; Lopeztegui, A.; Betanzos, A.; Hernández, R.
2011-01-01
Dada la importancia ecológica que tiene el erizo de mar Lytechinus variegatus y por formar parte de la dieta natural de muchos organismos marinos, entre los cuales se encuentran algunas especies de gran interés comercial, se realizó un estudio para describir las variaciones espaciales y temporales de la abundancia de sus poblaciones en el Golfo de Batabanó. La región fue dividida en dos sectores de estudio: Este (E) y Oeste (W) y se ubicaron 13 estaciones en las que se midió la sa...
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Broad Phylogenetic Occurrence of the Oxygen-Binding Hemerythrins in Bilaterians.
Costa-Paiva, Elisa M; Schrago, Carlos G; Halanych, Kenneth M
2017-10-01
Animal tissues need to be properly oxygenated for carrying out catabolic respiration and, as such, natural selection has presumably favored special molecules that can reversibly bind and transport oxygen. Hemoglobins, hemocyanins, and hemerythrins (Hrs) fulfill this role, with Hrs being the least studied. Knowledge of oxygen-binding proteins is crucial for understanding animal physiology. Hr genes are present in the three domains of life, Archaea, Bacteria, and Eukaryota; however, within Animalia, Hrs has been reported only in marine species in six phyla (Annelida, Brachiopoda, Priapulida, Bryozoa, Cnidaria, and Arthropoda). Given this observed Hr distribution, whether all metazoan Hrs share a common origin is circumspect. We investigated Hr diversity and evolution in metazoans, by employing in silico approaches to survey for Hrs from of 120 metazoan transcriptomes and genomes. We found 58 candidate Hr genes actively transcribed in 36 species distributed in 11 animal phyla, with new records in Echinodermata, Hemichordata, Mollusca, Nemertea, Phoronida, and Platyhelminthes. Moreover, we found that "Hrs" reported from Cnidaria and Arthropoda were not consistent with that of other metazoan Hrs. Contrary to previous suggestions that Hr genes were absent in deuterostomes, we find Hr genes present in deuterostomes and were likely present in early bilaterians, but not in nonbilaterian animal lineages. As expected, the Hr gene tree did not mirror metazoan phylogeny, suggesting that Hrs evolutionary history was complex and besides the oxygen carrying capacity, the drivers of Hr evolution may also consist of secondary functional specializations of the proteins, like immunological functions. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.
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Directory of Open Access Journals (Sweden)
Ipek F. Barut
2016-04-01
Full Text Available Marine or freshwater mussel species are found in large quantities around populated areas and accumulate metals in aquatic systems. Therefore, these organisms are used to monitor environmental pollution. Mytilus galloprovincialis is a generally accepted bioindicator of metal pollution and is used in this study. The aim of this study is to determine the changes in the environmental conditions since antiquity. M. galloprovincialis shells were used to monitor Chalcolithic pollution levels in Yarimburgaz Cave, one of the oldest settlements in Europe. Recent samples were collected from 12 stations on the coasts of the Northern Marmara Sea and the Bosphorus between May–September 2004. The environmental pollution substantially changed over the last 7500 years. The comparison of the geochemical characteristics of the environmental pollution observed in the Chalcolithic period and today revealed that pollution from both household and industrial chemicals has increased in Istanbul.
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Domínguez, Rula; Domínguez Godino, Jorge; Freitas, Cristiano; Machado, Inês; Bertocci, Iacopo
2015-03-01
Spatial and temporal patterns of abundance and distribution of sea urchins (Paracentrotus lividus) from intertidal rockpools of the north Portuguese coast were examined in relation to physical (surface, altitude, depth, topographic complexity and exposure) and biological (substrate cover by dominant organisms) habitat traits. The methodology was based on a multi-factorial design where the total number and the abundance of urchins in each of six size classes were sampled over a range of spatial scales, from 10s of cm to kms, and a temporal scale of five months. The results highlighted three main features of the studied system: (1) the largest proportion of variability of sea urchins occurred at the smallest scale examined; (2) urchins from different size classes showed different patterns of abundance in relation to habitat traits; (3) variables normally invoked as potential drivers of distribution of urchins at a range of scales, such as hydrodynamics and shore height, were relatively less important than other abiotic (i.e. pool area, pool mean depth calculated over five replicate measures and sand cover) and biological (i.e. space occupancy by the reef-forming polychaete Sabellaria alveolata and mussels vs. availability of bare rock) variables to provide a considerable contribution to the variability of sea urchins. Intertidal populations of sea urchins are abundant on many rocky shores, where they are socially and economically important as food resource and ecologically key as habitat modelers. This study provides new clues on relatively unstudied populations, with relevant implications for possible management decisions, including the implementation of protection schemes able to preserve the main recruitment, settlement and development areas of P. lividus.
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Beltrán, William; Wunderle, Joseph M.
2014-01-01
Abstract The seasonal dynamics of foliage arthropod populations are poorly studied in tropical dry forests despite the importance of these studies for understanding arthropod population responses to environmental change. We monitored the abundance, temporal distributions, and body size of arthropods in five naturalized alien and one native tree species to characterize arthropod seasonality in dry novel Prosopis–Leucaena woodlands in Puerto Rico. A branch clipping method was used monthly to sample foliage arthropod abundance over 39 mo. Seasonal patterns of rainfall and abundance within various arthropod taxa were highly variable from year to year. Abundance for most taxa did not show significant seasonality over the 3 yr, although most taxa had abundance peaks each year. However, Homoptera displayed high seasonality with significant temporal aggregations in each year. Formicidae, Orthoptera, and Coleoptera showed high variation in abundance between wet and dry periods, whereas Hemiptera were consistently more abundant in the wet period. Seasonal differences in mean abundance were found only in a few taxa on Tamarindus indica L. , Bucida buceras L. , Pithecellobium dulce , and (Roxburgh) Benth. Mean arthropod abundance varied among tree species, with highest numbers on Prosopis juliflora , (Swartz) De Candolle, Pi. dulce , Leucaena leucocephala , and (Lamarck) de Wit. Abundance of Araneae, Orthoptera, Coleoptera, Lepidoptera larvae, and all arthropods showed weak relationships with one or more climatic variables (rainfall, maximum temperature, or relative humidity). Body size of arthropods was usually largest during the dry periods. Overall, total foliage arthropod abundance showed no consistent seasonality among years, which may become a more common trend in dry forests and woodlands in the Caribbean if seasonality of rainfall becomes less predictable. PMID:25502036
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Wee, S L; Abdul Munir, M Z; Hee, A K W
2018-02-01
The Artocarpus fruit fly, Bactrocera umbrosa (Fabricius) (Diptera: Tephritidae), is an oligophagous fruit pest infesting Moraceae fruits, including jackfruit (Artocarpus heterophyllus Lamarck), a fruit commodity of high value in Malaysia. The scarcity of fundamental biological, physiological and ecological information on this pest, particularly in relation to behavioural response to phytochemical lures, which are instrumental to the success of many area-wide fruit fly control and management programmes, underpins the need for studies on this much-underrated pest. The positive response of B. umbrosa males to methyl eugenol (ME), a highly potent phytochemical lure, which attracts mainly males of many Bactrocera species, was shown to increase with increasing age. As early as 7 days after emergence (DAE), ca. 22% of males had responded to ME and over 50% by 10 DAE, despite no occurrence of matings (i.e. the males were still sexually immature). Male attraction to ME peaked from 10 to 27 DAE, which corresponded with the flies' attainment of sexual maturity. In wind-tunnel assays during the dusk courtship period, ME-fed males exhibited earlier calling activity and attracted a significantly higher percentage of virgin females compared with ME-deprived males. ME-fed males enjoyed a higher mating success than ME-deprived males at 1-day post ME feeding in semi-field assays. ME consumption also promotes aggregation behaviour in B. umbrosa males, as demonstrated in wind-tunnel and semi-field assays. We suggest that ME plays a prominent role in promoting sexual communication and enhancing mating performance of the Artocarpus fruit fly, a finding that is congruent with previous reports on the consequences of ME acquisition by other economically important Bactrocera species.
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A biomonitoring study: trace metals in algae and molluscs from Tyrrhenian coastal areas
International Nuclear Information System (INIS)
Conti, M.E.; Cecchetti, Gaetano
2003-01-01
Marine organisms were evaluated as possible biomonitors of heavy metal contamination in marine coastal areas. Concentrations of Cd, Cr, Cu, Pb, and Zn were measured in the green algae Ulva lactuca L., the brown algae Padina pavonica (L.) Thivy, the bivalve mollusc Mytilus galloprovincialis Lamarck, and the two gastropod molluscs Monodonta turbinata Born and Patella cerulea L. collected at six coastal stations in the area of the Gulf of Gaeta (Tyrrhenian Sea, central Italy). The coastal area of the Regional Park of Gianola and Monte di Scauri (a 'Protected Sea Park' area) was chosen as a control site. Seawater samples were also collected in each site to assess soluble and total metal concentrations and to gain additional information on both the environmental conditions of the area and possible bioaccumulation patterns. Metal concentrations detected in algae and molluscs did not show significant differences among all stations studied. Moreover, statistical analyses (ANOVA, multiple comparison tests, cluster analysis) showed that the Sea Park station was not significantly different from the others. The hypothesis that the Protected Sea Park would be cleaner than the others must therefore be reconsidered. Data from this study were also compared with those previously obtained from uncontaminated sites in the Sicilian Sea, Italy. The results show clearly differences between these two marine ecosystems. The species examined showed great accumulations of metals, with concentration factors (CFs) higher than 10,000 with respect to the concentrations (soluble fractions) in marine waters. Metal concentrations recorded in this area may be used for background levels for intraspecific comparison within the Tyrrhenian area, a body of water about which information is still very scarce
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Directory of Open Access Journals (Sweden)
Lavrov Dennis V
2009-12-01
Full Text Available Abstract Background The mitochondrial (mt genomes of sponges possess a variety of features, which appear to be intermediate between those of Eumetazoa and non-metazoan opisthokonts. Among these features is the presence of long intergenic regions, which are common in other eukaryotes, but generally absent in Eumetazoa. Here we analyse poriferan mitochondrial intergenic regions, paying particular attention to repetitive sequences within them. In this context we introduce the mitochondrial genome of Ircinia strobilina (Lamarck, 1816; Demospongiae: Dictyoceratida and compare it with mtDNA of other sponges. Results Mt genomes of dictyoceratid sponges are identical in gene order and content but display major differences in size and organization of intergenic regions. An even higher degree of diversity in the structure of intergenic regions was found among different orders of demosponges. One interesting observation made from such comparisons was of what appears to be recurrent invasions of sponge mitochondrial genomes by repetitive hairpin-forming elements, which cause large genome size differences even among closely related taxa. These repetitive hairpin-forming elements are structurally and compositionally divergent and display a scattered distribution throughout various groups of demosponges. Conclusion Large intergenic regions of poriferan mt genomes are targets for insertions of repetitive hairpin- forming elements, similar to the ones found in non-metazoan opisthokonts. Such elements were likely present in some lineages early in animal mitochondrial genome evolution but were subsequently lost during the reduction of intergenic regions, which occurred in the Eumetazoa lineage after the split of Porifera. Porifera acquired their elements in several independent events. Patterns of their intra-genomic dispersal can be seen in the mt genome of Vaceletia sp.
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Khattab, Rafat Afifi; Elbandy, Mohamed; Lawrence, Andrew; Paget, Tim; Rae-Rho, Jung; Binnaser, Yaser S; Ali, Imran
2018-01-01
Secondary metabolism in marine organisms produces a diversity of biologically important natural compounds that are not present in terrestrial species. Sea cucumbers belong to the invertebrate Echinodermata and are famous for their nutraceutical, medical and food values. They are known for possession triterpenoid glycosides (saponins) with various ecological roles. The current work aimed to separate, identify and test various biological activities (antibacterial, antifungal, antileishmanial and anticancer properties) of saponins produced by the holothurian Pearsonothuria graeffei from the Red Sea, Egypt. The structures were identified by 1D and 2D NMR (1H, 13C, TOCSY, COSY, HSQC, HMBC, and ROESY) experiments and acid hydrolysis. The crude and purified fractions was analyzed using matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS)/MS to identify saponins and characterize their molecular structures. Partially purified fraction, mainly containing compounds 1 and 2, was screened for its antifungal activity against three clinical isolates of Candida albicans (Candida 580 (1), Candida 581(2) and Candida MEO47228. Antileishmanial activity against Leishmania major and toxicity on colon cell-line were also evaluated. Two lanostane type sulfated triterpene monoglycosides were isolated from the Holothurian Pearsonothuria graeffei from the Red Sea, Egypt. Holothurin A (1) and echinoside A (2) triterpene saponins were separated by reversed phase semi-preparative HPLC. LC50 values (µg/mL); calculated for the fraction containing saponins 1 and 2 as major constituents; against Candida albicans, Leishmania major and colon cell-line were 10, 20 and 0.50, respectively. Consequently, this study demonstrated the potential use of sea cucumber Pearsonothuria graeffei not only as appreciated functional food or nutraceuticals but also as the source of functional ingredients for pharmaceutical products with antifungal, antileishmanial and anticancer properties
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Martynov, Alexander; Ishida, Yoshiaki; Irimura, Seiichi; Tajiri, Rie; O'Hara, Timothy; Fujita, Toshihiko
2015-01-01
Current taxonomy offers numerous approaches and methods for species delimitation and description. However, most of them are based on the adult characters and rarely suggest a dynamic representation of developmental transformations of taxonomically important features. Here we show how the underestimation of ontogenetic changes may result in long term lack of recognition of a new species of one of the most common ophiacanthid brittle stars (Echinodermata: Ophiuroidea) from the North Pacific. Based on vast material collected predominantly by various Japanese expeditions in the course of more than 50 years, and thorough study of appropriate type material, we revise the complex of three common species of the ophiuroid genus Ophiacantha which have been persistently confused with each other. The present study thus reveals the previously unrecognized new species Ophiacantha kokusai sp.nov. which is commonly distributed off the Pacific coast of Japan. The new species shows developmental differentiation from the closely related species Ophiacantha rhachophora H. L. Clark, 1911 and retains clearly expressed early juvenile features in the adult morphology. Another species, Ophiacantha clypeata Kyte, 1977, which had been separated from O. rhachophora, is in turn shown to be just a juvenile stage of another North Pacific species, Ophiacantha trachybactra H.L. Clark, 1911. For every species, detailed morphological data from both adult and juvenile specimens based on scanning electron microscopy are presented. A special grinding method showing complex internal features has been utilized for the first time. For all three species in this complex, a clear bathymetric differentiation is revealed: O. rhachophora predominantly inhabits shallow waters, 0-250 m, the new species O. kokusai lives deeper, at 250-600 m, and the third species, O. trachybactra, is found at 500-2,000 m. The present case clearly highlights the importance of considering developmental transformations, not only for
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Temporal and spatial distribution of the meiobenthic community in Daya Bay, South China Sea
Tang, L.; Li, H. X.; Yan, Y.
2012-04-01
Spatial and temporal biodiversity patterns of the meiobenthos were studied for the first time in Daya Bay, which is a tropical semi-enclosed basin located in the South China Sea. The abundance, biomass, and composition of the meiobenthos and the basic environmental factors in the bay were investigated. The following 19 taxonomic groups were represented in the meiofauna: Nematoda, Copepoda, Polychaeta, Oligochaeta, Kinorhyncha, Gastrotricha, Ostracoda, Bivalvia, Turbellaria, Nemertinea, Sipuncula, Hydroida, Amphipoda, Cumacea, Halacaroidea, Priapulida, Echinodermata, Tanaidacea, and Rotifera. Total abundance and biomass of the meiobenthos showed great spatial and temporal variation, with mean values of 993.57 ± 455.36 ind cm-2 and 690.51 ± 210.64 μg 10 cm-2, respectively. Nematodes constituted 95.60 % of the total abundance and thus had the greatest effect on meiofauna quantity and distribution, followed by copepods (1.55 %) and polychaetes (1.39 %). Meiobenthos abundance was significantly negatively correlated with water depth at stations (r=-0.747, P<0.05) and significantly negatively correlated with silt-clay content (r=-0.516, P<0.01) and medium diameter (r=-0.499, P<0.01) of the sediment. Similar results were found for correlations of biomass and abundance of nematodes with environmental parameters. Polychaete abundance was positively correlated with the bottom water temperature (r=0.456, P<0.01). Meiobenthos abundance differed significantly among seasons (P<0.05), although no significant difference among stations and the interaction of station × season was detected by two-way ANOVA. In terms of vertical distribution, most of the meiobenthos was found in the surface layer of sediment. This pattern was apparent for nematodes and copepods, but a vertical distribution pattern for polychaetes was not as obvious. Based on the biotic indices and analyses of their correlations and variance, the diversity of this community was likely to be influenced by
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Leal, Miguel Costa; Puga, João; Serôdio, João; Gomes, Newton C. M.; Calado, Ricardo
2012-01-01
It is acknowledged that marine invertebrates produce bioactive natural products that may be useful for developing new drugs. By exploring untapped geographical sources and/or novel groups of organisms one can maximize the search for new marine drugs to treat human diseases. The goal of this paper is to analyse the trends associated with the discovery of new marine natural products from invertebrates (NMNPI) over the last two decades. The analysis considers different taxonomical levels and geographical approaches of bioprospected species. Additionally, this research is also directed to provide new insights into less bioprospected taxa and world regions. In order to gather the information available on NMNPI, the yearly-published reviews of Marine Natural Products covering 1990–2009 were surveyed. Information on source organisms, specifically taxonomical information and collection sites, was assembled together with additional geographical information collected from the articles originally describing the new natural product. Almost 10000 NMNPI were discovered since 1990, with a pronounced increase between decades. Porifera and Cnidaria were the two dominant sources of NMNPI worldwide. The exception was polar regions where Echinodermata dominated. The majority of species that yielded the new natural products belong to only one class of each Porifera and Cnidaria phyla (Demospongiae and Anthozoa, respectively). Increased bioprospecting efforts were observed in the Pacific Ocean, particularly in Asian countries that are associated with the Japan Biodiversity Hotspot and the Kuroshio Current. Although results show comparably less NMNPI from polar regions, the number of new natural products per species is similar to that recorded for other regions. The present study provides information to future bioprospecting efforts addressing previously unexplored taxonomic groups and/or regions. We also highlight how marine invertebrates, which in some cases have no commercial value
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Amri, Sandra; Samar, Mohamed-Faouzi; Sellem, Fériel; Ouali, Kheireddine
2017-09-15
In this study, sea urchin Paracentrotus lividus were sampled seasonally at three stations during 2012 in the coastal areas of the Gulf of Annaba (southeast Mediterranean). For all sea urchins, the gonad index was calculated to determine sea urchin reproductive status. Moreover, a set of biochemical parameters, including biomarkers and oxidative stress parameters, was measured in gonads. The pesticides and physiochemical parameters were measured and dosed in sea water. The results obtained highlighted that the levels of pesticide were generally low and below those commonly applied by environmental quality standards (EQS), indicating that no alarm state is currently present in the Gulf of Annaba. In addition to pollution, seasonal change is an important factor influencing biomarker activity, and the significant increases in biomarker levels in spring are a major observed trend. This activity may also be related to reproductive status. Seasonal variability was confirmed by the significant results of the Kruskal-Wallis test and by the high degree of divergence between seasons in PCA, with a total of 83.83% of variance explained. These results indicate that environmental factors that vary seasonally may affect the antioxidant status of the sea urchin Paracentrotus lividus. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Gladfelter, E. H.
2007-12-01
Many Acropora palmata colonies consist of an encrusting basal portion and erect branches. Linear growth of the skeleton results in extension along the substrate (encrusting growth), lengthening of branches (axial growth) and thickening of branches and crust (radial growth). Scanning Electron Microscopy is used to compare the mechanisms of skeletal extension between encrusting growth and axial growth. In encrusting growth, the distal margin of the skeleton lacks corallites (which develop about 1 mm from the edge); in contrast, in axial growth, axial corallites along the branch tip form the distal portion of the skeleton. In both locations, the distal margin of the skeleton consists of a lattice-like structure composed of rods that extend from the body of the skeleton and bars that connect these rods. An actively extending skeleton is characterized by sharply pointed rods and partially developed bars. Distal growth of rods (and formation of bars) is effected by the formation of new sclerodermites. Each sclerodermite begins with the deposition of fusiform crystals (that range in length from 1 to 5 μm). These provide a surface for nucleation and growth of spherulitic tufts, clusters of short (<1 μm long) aragonite needles. The needles that are oriented perpendicular to the axis of the skeletal element (rod or bar), and perpendicular to the overlying calicoblastic epithelium, continue extension to appear on the surface of the skeleton as 10-15 μm wide bundles (of needle tips) called fasciculi. However, some crusts that abut competitors for space have a different morphology of skeletal elements (rods and bars). The distal edge of these crusts terminates in blunt coalescing rods, and bars that are fully formed. Absence of fusiform crystals, lack of sharply pointed rods and bars, and full development of sclerodermites characterize a skeletal region that has ceased, perhaps only temporarily, skeletal extension.
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Time- and depth-wise trophic niche shifts in Antarctic benthos.
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Edoardo Calizza
Full Text Available Climate change is expected to affect resource-consumer interactions underlying stability in polar food webs. Polar benthic organisms have adapted to the marked seasonality characterising their habitats by concentrating foraging and reproductive activity in summer months, when inputs from sympagic and pelagic producers increase. While this enables the persistence of biodiverse food webs, the mechanisms underlying changes in resource use and nutrient transfer are poorly understood. Thus, our understanding of how temporal and spatial variations in the supply of resources may affect food web structure and functioning is limited. By means of C and N isotopic analyses of two key Antarctic benthic consumers (Adamussium colbecki, Bivalvia, and Sterechinus neumayeri, Echinoidea and Bayesian mixing models, we describe changes in trophic niche and nutrient transfer across trophic levels associated with the long- and short-term diet and body size of specimens sampled in midsummer in both shallow and deep waters. Samplings occurred soon after the sea-ice broke up at Tethys Bay, an area characterised by extreme seasonality in sea-ice coverage and productivity in the Ross Sea. In the long term, the trophic niche was broader and variation between specimens was greater, with intermediate-size specimens generally consuming a higher number of resources than small and large specimens. The coupling of energy channels in the food web was consequently more direct than in the short term. Sediment and benthic algae were more frequently consumed in the long term, before the sea-ice broke up, while consumers specialised on sympagic algae and plankton in the short term. Regardless of the time scale, sympagic algae were more frequently consumed in shallow waters, while plankton was more frequently consumed in deep waters. Our results suggest a strong temporal relationship between resource availability and the trophic niche of benthic consumers in Antarctica. Potential
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Thiago Junqueira Izzo
2011-01-01
Full Text Available Os benefícios obtidos por um organismo em uma associação mutualística podem variar em função de fatores ambientais, bem como entre as diferentes espécies que podem estar associadas. Neste trabalho demonstramos que quatro espécies de formigas, Crematogaster brasiliensis, Allomerus octoarticulatus e duas não identificadas do gênero Azteca podem ser encontradas associadas à mirmecófita Cordia nodosa em florestas ripárias sul-amazônicas. Essa composição de espécies de formigas é mais similar a encontrada na Amazônia Andina do que aquela da Amazônia Central brasileira. A colonização por formigas parece ser determinante, pois diminuiu a herbivoria e, consequentemente, aumentou a probabilidade de C. nodosa produzir frutos. Adicionalmente, mesmo não havendo diferença na herbivoria entre plantas colonizadas pelas diferentes espécies de formigas, a probabilidade de uma planta colonizada por formigas do gênero Allomerus produzir frutos é menor do que quando colonizadas pelas outras espécies de formigas. Esse estudo demonstra a dependência de C. nodosa pela colonização de formigas para sua reprodução. Contudo, conforme outros estudos realizados em outras áreas da Amazônia demonstram, nossos resultados também sugerem que Allomerus pode estar castrando as plantas hospedeiras, agindo como parasita em toda a sua distribuição geográfica.The benefits obtained by an organism when involved in a mutualistic interaction vary depending on environmental factors, as well as among the identity of the involved species. In this study, we showed that four ant species, Crematogaster brasiliensis, Allomerus octoarticulatus, and two unidentified Azteca species can be found associated to the myrmecophite Cordia nodosa in riparian forests in the South of Amazonia. This composition of ant-associated species is more similar in forests of Andean Amazon than in Central Amazonia. The colonization of an ant colony on C. nodosa seems to be vital in order to decrease herbivory, as increased the probability of a plant sets fruits. Moreover, even though we did not find significant differences in herbivory among plants colonized by different ant species, the probability of a plant produces fruits is much lower when it is colonized by Allomerus ants. Overall, this study shows that C. nodosa depends on ants to reproduce. However, based on other empirical studies across the Amazon, our results also suggest that Allomerus ants can act as flower castrator, acting as a parasite over its geographic range.
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RUBÉN E. AVENDAÑO
2001-09-01
Full Text Available Argopecten purpuratus es uno de los recursos marinos de mayor importancia comercial en Chile. Una de las etapas críticas en el cultivo de esta especie, es el traspaso de las post-larvas al medio natural, ya que durante este período se produce un significativo descenso en el número de post-larvas. Los factores que provocan estas bajas sobrevivencias pueden ser diversos, pero aún son desconocidos. En el presente estudio se evaluó la incidencia en la sobrevivencia y crecimiento de las variables origen de las larvas, distribución de los colectores en diferentes estaciones de Bahía Inglesa, III región (27° 03' 24" S, 70° 51' 30" O y los cambios en la bacterioflora asociadas a las post-larvas. Los organismos utilizados en el estudio fueron obtenidas desde los "hatcheries" de Cultivos Marinos Internacionales (III región y Cultivos Guayacán (IV región. Los resultados del estudio indican claramente que la ubicación y origen de las post-larvas en la bahía incide en la sobrevivencia de éstas. Sin embargo, el crecimiento no es afectado por las variables estudiadas (P Argopecten purpuratus is one of the most commercially important marine resources in Chile. One of the most critical steps in the massive culture of this species is the transference of postlarvae from hatchery production to the sea where significant mortality regularly occurs. The factors behind this low survival rate are probably diverse, and are as yet unknown. In the present study, postlarval survival and growth was observed as a function of origin of postlarvae, distribution of postlarvae in the bay, and microbial loading of the postlarvae. Survival rates were measured for different sites in Bahia Inglesa, Chile (27° 03' 24" S, 70° 51' 30" W as well as changes in the bacterioflora of the postlarvae. Postlarvae utilized in the study were obtained from Cultivos Marinos Internacionales (III Región and Cultivos Guayacan (IV Región. Results of the study clearly indicated that survival in culture of the postlarvae was related to their location in the bay and the origin of the postlarvae. However, the growth of the post-larvae is not affected (P < 0.05. Microbiologically, it was observed that Vibrio spp. were the bacterial component most represented among strains isolated from the postlarvae (53.36 % from both populations studied. Principal component analysis revealed no differences between cultivable vibrios from both cultures. However, microflora from the Guayacan group were less susceptible to increases in bacteria originating in their surrounding environment
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Ou, Xiufang; Zhang, Yunhong; Xu, Chunming; Lin, Xiuyun; Zang, Qi; Zhuang, Tingting; Jiang, Lili; von Wettstein, Diter; Liu, Bao
2012-01-01
that environmental induction of heritable modifications in DNA methylation provides a plausible molecular underpinning for the still contentious paradigm of inheritance of acquired traits originally put forward by Jean-Baptiste Lamarck more than 200 years ago.
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The unionid (Bivalvia) fauna of the Sipsey River in northwestern Alabama, an aquatic hotspot
McCullagh, W. Henry; Williams, James D.; McGregor, Stuart W.; Pierson, J. Malcom; Lydeard, Charles
2002-01-01
Recent surveys for unionid bivalves were conducted in the mainstem of the Sipsey River and headwater tributaries (Tombigbee River drainage) during the summer and autumn of 1996-1999. A total of 35 species and 22 genera were found. Museum records from the upper Sipsey, based largely on the efforts of H. H. Smith during 1910-11, raised the total number of recorded unionids in the Sipsey to 42. Smith documented 25 species in the river; however, most of his collections were made in the mid- to upper-Sipsey, which has lower diversity. The three most common recently observed species in descending order of abundance were Quadrula asperata (I. Lea, 1861), Pleurobema decisum (I. Lea, 1831), and Tritogonia verrucosa (Rafinesque, 1820). Federally listed species observed recently include Lampsilis perovalis (Conrad, 1834) (threatened), Medionidus acutissimus (I. Lea, 1831) (threatened), P. decisum (endangered), P. perovatum (Conrad, 1834) (endangered), and Potamilus inflatus (I. Lea, 1831) (threatened). Species not observed recently but recorded in prior surveys include Anodontoides radiatus (Conrad, 1834), Arcidens confragosus (Say, 1829), Plectomerus dombeyanus (Valenciennes, 1827), Q. metanevra (Rafinesque, 1820), Q. stapes (I. Lea, 1831) (federally endangered), P. taitianum (I. Lea, 1834) (federally endangered), and Toxolasma parvus (Barnes, 1823). Many, species are known recently or historically by only five or fewer recorded specimens including: A. radiatus, Elliptio arctata (Conrad, 1834), Ligumia recta (Lamarck, 1819), P. taitianum, P. inflatus, Q. aspera (Lea, 1831), Q. metanevra, Q. stapes, T. parvus, Truncilla donaciformis (I. Lea, 1828), Uniomerus tetralasmus (Say, 1831), Utterbackia imbecillis (Say, 1829), A. confragosus, and P. dombeyanus. Unlike the mussel fauna of most Alabama streams, that of the Sipsey River is still relatively intact in terms of species richness despite impacts from mining, silvicultural, and agricultural activities. A concerted effort
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Gabora, Liane; Kauffman, Stuart
2016-04-01
Dietrich and Haider (Psychonomic Bulletin & Review, 21 (5), 897-915, 2014) justify their integrative framework for creativity founded on evolutionary theory and prediction research on the grounds that "theories and approaches guiding empirical research on creativity have not been supported by the neuroimaging evidence." Although this justification is controversial, the general direction holds promise. This commentary clarifies points of disagreement and unresolved issues, and addresses mis-applications of evolutionary theory that lead the authors to adopt a Darwinian (versus Lamarckian) approach. To say that creativity is Darwinian is not to say that it consists of variation plus selection - in the everyday sense of the term - as the authors imply; it is to say that evolution is occurring because selection is affecting the distribution of randomly generated heritable variation across generations. In creative thought the distribution of variants is not key, i.e., one is not inclined toward idea A because 60 % of one's candidate ideas are variants of A while only 40 % are variants of B; one is inclined toward whichever seems best. The authors concede that creative variation is partly directed; however, the greater the extent to which variants are generated non-randomly, the greater the extent to which the distribution of variants can reflect not selection but the initial generation bias. Since each thought in a creative process can alter the selective criteria against which the next is evaluated, there is no demarcation into generations as assumed in a Darwinian model. We address the authors' claim that reduced variability and individuality are more characteristic of Lamarckism than Darwinian evolution, and note that a Lamarckian approach to creativity has addressed the challenge of modeling the emergent features associated with insight.
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On Darwin's 'metaphysical notebooks'. I: teleology and the project of a theory.
Calabi, L
2001-01-01
Huxley's essay On the Reception of the 'Origin of Species' brings us close to the issue of cause and of why- and how-questions in the understanding of the living world. The present contribution, which is divided into two parts, reviews the problem of Teleology as conceived by Huxley and re-examines Darwin as the author who revealed the existence of a 'foundations problem' in the explanation of an entire realm of nature, i.e., the problem of explaining such realm in terms of its own, specific legality, or iuxta sua propria principia. In the first part the enquiry is mainly focused on the secularization of natural history after Paley; in the second part it is mainly focused on the desubjectivization of the inquiry into natural history after Erasmus Darwin and Lamarck. The second part will be published in the next issue of Rivista di Biologia/Biology Forum. In the first part below an analysis is made of Notebooks M and N. The author disputes the correctness of conceiving them only as the works where Darwin envisages the 'metaphysical' themes later to become the subject of The Expression of the Emotions. He suggests to conceive of them also as the works where Darwin defines the terms of the general project of his own, peculiar evolutionary theory. The author then outlines the intellectual progress of Darwin from the inosculation to the transmutation hypotheses. Darwin's reading of Malthus appears to be analytically decisive, because it offers him the vintage point to attack the metaphysical and theological citadels on the morphological side. Darwin is thus able to re-consider Erasmus' comprehensive zoonomic project, by displacing it, however, from the old idea of the scala naturae to the new one of the "coral of life", and by emphasising the distinction between "the fittest" and "the best" vs. the tradition of Natural Theology.
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Beltrán, William; Wunderle, Joseph M
2014-01-01
The seasonal dynamics of foliage arthropod populations are poorly studied in tropical dry forests despite the importance of these studies for understanding arthropod population responses to environmental change. We monitored the abundance, temporal distributions, and body size of arthropods in five naturalized alien and one native tree species to characterize arthropod seasonality in dry novel Prosopis-Leucaena woodlands in Puerto Rico. A branch clipping method was used monthly to sample foliage arthropod abundance over 39 mo. Seasonal patterns of rainfall and abundance within various arthropod taxa were highly variable from year to year. Abundance for most taxa did not show significant seasonality over the 3 yr, although most taxa had abundance peaks each year. However, Homoptera displayed high seasonality with significant temporal aggregations in each year. Formicidae, Orthoptera, and Coleoptera showed high variation in abundance between wet and dry periods, whereas Hemiptera were consistently more abundant in the wet period. Seasonal differences in mean abundance were found only in a few taxa on Tamarindus indica L., Bucida buceras L., Pithecellobium dulce, and (Roxburgh) Benth. Mean arthropod abundance varied among tree species, with highest numbers on Prosopis juliflora, (Swartz) De Candolle, Pi. dulce, Leucaena leucocephala, and (Lamarck) de Wit. Abundance of Araneae, Orthoptera, Coleoptera, Lepidoptera larvae, and all arthropods showed weak relationships with one or more climatic variables (rainfall, maximum temperature, or relative humidity). Body size of arthropods was usually largest during the dry periods. Overall, total foliage arthropod abundance showed no consistent seasonality among years, which may become a more common trend in dry forests and woodlands in the Caribbean if seasonality of rainfall becomes less predictable. © The Author 2014. Published by Oxford University Press on behalf of the Entomological Society of America.
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Nelson A F Miranda
Full Text Available Tarebia granifera (Lamarck, 1822 is originally from South-East Asia, but has been introduced and become invasive in many tropical and subtropical parts of the world. In South Africa, T. granifera is rapidly invading an increasing number of coastal lakes and estuaries, often reaching very high population densities and dominating shallow water benthic invertebrate assemblages. An assessment of the feeding dynamics of T. granifera has raised questions about potential ecological impacts, specifically in terms of its dietary overlap with native gastropods.A stable isotope mixing model was used together with gut content analysis to estimate the diet of T. granifera and native gastropod populations in three different coastal lakes. Population density, available biomass of food and salinity were measured along transects placed over T. granifera patches. An index of isotopic (stable isotopes dietary overlap (IDO, % aided in interpreting interactions between gastropods. The diet of T. granifera was variable, including contributions from microphytobenthos, filamentous algae (Cladophora sp., detritus and sedimentary organic matter. IDO was significant (>60% between T. granifera and each of the following gastropods: Haminoea natalensis (Krauss, 1848, Bulinus natalensis (Küster, 1841 and Melanoides tuberculata (Müller, 1774. However, food did not appear to be limiting. Salinity influenced gastropod spatial overlap. Tarebia granifera may only displace native gastropods, such as Assiminea cf. ovata (Krauss, 1848, under salinity conditions below 20. Ecosystem-level impacts are also discussed.The generalist diet of T. granifera may certainly contribute to its successful establishment. However, although competition for resources may take place under certain salinity conditions and if food is limiting, there appear to be other mechanisms at work, through which T. granifera displaces native gastropods. Complementary stable isotope and gut content analysis can
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Rony Roberto Ramos Vieira
Full Text Available ABSTRACT: The abundance and distribution of larval phases of the Portunidae found in the estuary of the Patos Lagoon and the coastal region were studied during two years (1995 and 1999. A conical net (165 cm long, 60 cm mouth, and 330 µm mesh equipped with a flowmeter was towed for three minutes at 2 knots at six stations within the estuary and four stations in the coastal region. Samplings were carried out on the surface and near the bottom. At each sampling location, the salinity and temperature were also recorded. In 1995, the zoeae of Arenaeus cribrarius (Lamarck, 1818, Callinectes sapidus Rathbun, 1896 and Achelous spinicarpus Stimpson, 1871 were caught, resulting in a total abundance of 121.98 ind.100 m-3 (90.95 ind.100 m-3 on the surface and 31.03 ind.100 m-3 near the bottom. A total of 452.27 ind.100 m-3 were caught in the megalopa phase (13.49 ind.100 m-3 on the surface and 438.78 ind.100 m-3 near the bottom. In 1999, only zoeae of C. sapidus were caught, resulting in a total abundance of 419.78 ind.100 m-3 (386.98 ind.100 m-3 on the surface and 32.8 ind.100 m-3 near the bottom. Megalopae of these three species were caught, resulting in a total abundance of 179.91 ind.100 m-3 (25.38 ind.100 m-3 on surface and 154.53 ind.100 m-3 near the bottom. Summer was the season with the highest abundance of larvae in both years. During spring and summer, spawning was observed in the estuarine region of the Patos Lagoon.
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Samantha A. Seixas
2010-04-01
Full Text Available The original description of Temnocephala iheringi Haswell, 1893 was based on specimens collected by Hermann von Ihering from undetermined ampullariid apple snails, which at that time were identified as Ampullaria sp., and sent to William H. Haswell, with the type locality simply indicated as Brazil. The type specimens studied by Haswell were not found in the scientific collections of Brazil, Europe or Australia, and should be considered lost. In 1941, Pereira & Cuocolo collected specimens from apple snails, identified as Pomacea lineata (Spix in Wagner, 1827, at two localities (Guaicurús and Salobra in the state of Mato Grosso do Sul, central Brazil. These specimens could not be located either and should, thus, be considered lost as well. Pomacea canaliculata (Lamarck, 1822, the main host of T. iheringi in southern Brazil, is known to have a geographical distribution that reaches Uruguay and 400 km beyond the province of Buenos Aires, Argentina. Three hundred and one mollusks were collected from 1999 to 2007. Temnocephalans found in the pallial cavity presented a greenish body pigmentation (adults and lacked eye pigment of any color, including the red-eye pigment, typical of Neotropical species of Temnocephala Blanchard, 1849; straight cirrus, with a thick band at base of the introvert' swelling; and a single, circular, asymmetric vaginal sphincter, wider in diameter in the posterior portion. As the species occurs concurrently with two other species, at least in P. canaliculata from Rio Grande do Sul, the eggs of T. iheringi could not be reliably distinguished. A redescription of the species is provided. A comparison of data from the present work with those of earlier papers published on T. iheringi from Argentina showed that the Argentinean specimens had the smallest measurements.
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Samantha A. Seixas
2010-06-01
Full Text Available The impact of the discovery of Temnocephala haswelli Ponce de Léon, 1989, described as ectosymbionts of ampullariid apple snails outside of Uruguay, motivated us to collect a large number of specimens of Pomacea canaliculata (Lamarck, 1822 from several localities in the southern portion of the state of Rio Grande do Sul. This species was recorded three times after its description: in a study of chromosomes, in a study about the ultrastructure of the collar receptor cells, and in a study of the Haswell glands, all conducted in Uruguay. A total of 301 specimens of P. canaliculata were collected from 1999 to 2007. Temnocephalans found in the pallial cavity were identified as T. haswelli, which occurred in single infestations or concurrently with Temnocephala iheringi Haswell, 1893. Helminths usually showed a light-orange body pigmentation and conspicuous, intense red-eye pigment. Many taxonomic characters evidenced by several techniques were documented photographically for the first time. The typical curved cirrus, approximately 90°, typical of the species, showed some variation in the width of the shaft base, whereas the first longitudinal row of spines of the introvert appeared with shorter spines. The vagina was found to be thick-walled, but not very muscular, and to have a single, large and slightly asymmetrical sphincter, with the posterior portion of slightly larger diameter. Eggs were observed in the umbilicus and along the suture, but predominantly in the body whorl of the shell. Egg peduncles were found to be very short or, most of the time, the eggs were sessile, always with a long apical filament. The rounded shape of the dorsolateral 'excretory' syncytial epidermal plates had external margins reaching the ventrolateral region of the body and eccentric nephridiopores. This is the first record of the species outside Uruguay and in Brazil.
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Mathenge, C W; Holford, P; Hoffmann, J H; Zimmermann, H G; Spooner-Hart, R; Beattie, G A C
2009-12-01
Cylindropuntia fulgida (Engelmann) F.M. Knuth var. fulgida (Engelmann) F.M. Knuth (Cff) (Caryophyllales: Cactaceae) is native to Mexico and Arizona and was introduced into South Africa for ornamental purposes. It subsequently became highly invasive, necessitating control. The cochineal insect, Dactylopius tomentosus (Lamarck) (Hemiptera: Dactylopiidae), was selected as a potential biological control agent based on its restricted host range among Cylindropuntia species and previous success in controlling C. imbricata (DC.) F. Knuth (Ci). Eight D. tomentosus provenances (Cholla, Cholla E, Fulgida, Mamillata, Imbricata, Tunicata U, Tunicata V and Rosea) from Cylindropuntia species in their native ranges were reared on Cff, whilst Cholla and Imbricata were also reared on Ci. Large differences were found in the development and survival of crawlers, and in the reproductive capacity of females. Three subjective categories of provenance interaction with host plants were identified based on a fitness index (FI) calculated from data relating to crawler survival, female development time and fecundity: (i) thriving (FI > or = 1) - insects had shorter developmental times, high crawler survival and highly fecund females (Cholla); (ii) surviving (FI0) - insects had extended development times, low crawler survival and low fecundity (Imbricata, Fulgida and Mamillata); and (iii) dying (FI = 0) - insects died before or at the second instar (Rosea, Tunicata U and Tunicata V). Cholla, therefore, is highly suitable for biological control of Cff in South Africa. In addition, Cholla thrived on Cff but only survived on Ci whilst, in contrast, Imbricata thrived on Ci but only survived on Cff. This differential ability of provenances to thrive or survive on different host plants demonstrated that host adapted biotypes of D. tomentosus exist; therefore, biotypes should be taken into account when considering this species as a biological control agent of cactus weeds.
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International Nuclear Information System (INIS)
Tyler, P.A.; Muirhead, A.
1986-07-01
The reproductive biology of Porcellanaster ceruleus, Hyphalaster inermis and Styrachaster horridus is described. P. ceruleus was collected as part of the time series study in the rockall Trough, N.E. Atlantic. This species had a maximum size of 7.0mm arm radius although maximum size known is 36.0mm arm radius. Relatively few eggs are produced and in these samples grow to a maximum size of 230μm. There was no evidence of reproductive seasonality. In Hyphalaster inermis and Styrachaster horridus the eggs grow to 600μm diameter. At this size the cytoplasm is reticulate and filled with neutral fat whilst the periphery is an amorphous layer. Development of the testes in all three species appears typical of deep-sea asteroids. (author)
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Elliot Scanes
Full Text Available Ocean acidification is predicted to have severe consequences for calcifying marine organisms especially molluscs. Recent studies, however, have found that molluscs in marine environments with naturally elevated or fluctuating CO2 or with an active, high metabolic rate lifestyle may have a capacity to acclimate and be resilient to exposures of elevated environmental pCO2. The aim of this study was to determine the effects of near future concentrations of elevated pCO2 on the larval and adult stages of the mobile doughboy scallop, Mimachlamys asperrima from a subtidal and stable physio-chemical environment. It was found that fertilisation and the shell length of early larval stages of M. asperrima decreased as pCO2 increased, however, there were less pronounced effects of elevated pCO2 on the shell length of later larval stages, with high pCO2 enhancing growth in some instances. Byssal attachment and condition index of adult M. asperrima decreased with elevated pCO2, while in contrast there was no effect on standard metabolic rate or pHe. The responses of larval and adult M. asperrima to elevated pCO2 measured in this study were more moderate than responses previously reported for intertidal oysters and mussels. Even this more moderate set of responses are still likely to reduce the abundance of M. asperrima and potentially other scallop species in the world's oceans at predicted future pCO2 levels.
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Hueda, Marcelo Akira
2009-01-01
Publicado anonimamente em 1844, o livro Vestiges of the natural history of creation desencadeou uma das maiores discussões públicas que ocorreram durante o século XIX. Seu autor, Robert Chambers, defendeu a transmutação dos seres vivos e a origem de novas espécies através de causas naturais. O primeiro objetivo desta dissertação é descrever algumas concepções evolutivas apresentadas neste livro e o segundo é compará-las à versão final da teoria da progressão dos animais de La...
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Andréa C. Tomazelli
2003-12-01
Full Text Available Studies were carried out to investigate the contamination of Piracicaba and Mogi-Guaçu River basins (São Paulo State, Southeastern, Brazil for heavy metals (Cd and Pb, using the limnic bivalve Anodontites trapesialis as a biological monitor. The results showed that the concentrations of Pb were higher than the control group in both basins, showing the bioavailability of this non-essential element in the basins. The concentrations were higher in the Mogi-Guaçu than in the Piracicaba basin, and in the slightly contaminated sites in both basins. There was no correlation between the degree of human impact and Cd and Pb concentrations, it was not possible to infer about concentrations of these heavy metals in the bivalves based only in a broad evaluation of human impact.O principal objetivo deste estudo foi investigar a contaminação pelos metais pesados Cd e Pb nas bacias dos rios Piracicaba e Mogi-Guaçu (Estado de São Paulo, Brasil, utilizando o bivalve limnico Anodontites trapesialis como indicador biológico. As bacias estudadas apresentam diferentes graus de impacto, sendo a qualidade da água geralmente melhor na bacia do rio Mogi-Guaçu. Os teores de Pb detectados nos bivalves não podem ser considerados críticos, contudo, houve acúmulo em relação ao grupo de controle em ambas as bacias, especialmente na bacia do rio Mogi-Guaçu. As maiores concentrações dos elementos, especialmente Pb, foram observadas nos locais menos poluídos e na bacia menos degradada. Este fato sugere que estas concentrações não estão sendo afetadas apenas pelas atividades antrópicas nas bacias, mas deve-se considerar também fatores que afetem a biodisponibilidade ou fontes específicas e não pontuais.
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Tourón Besada, Noelia
2013-01-01
El erizo de mar, Paracentrotus lividus, se distribuye por las costas del Atlántico norte y del mar Mediterráneo. La tradición de comer erizo de mar en España es típica principalmente de Asturias, Cataluña y Cantabria; la zona de extracción principal para su posterior exportación es Galicia. La oferta de este producto aumenta progresivamente en nuestros mercados, lo que está provocando una sobreexplotación de erizos de las costas gallegas, pues es una especie con lenta recuperación y crecimien...
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Lina Sun
Full Text Available BACKGROUND: Sea cucumbers (Holothuroidea; Echinodermata have the capacity to regenerate lost tissues and organs. Although the histological and cytological aspects of intestine regeneration have been extensively studied, little is known of the genetic mechanisms involved. There has, however, been a renewed effort to develop a database of Expressed Sequence Tags (ESTs in Apostichopus japonicus, an economically-important species that occurs in China. This is important for studies on genetic breeding, molecular markers and special physiological phenomena. We have also constructed a library of ESTs obtained from the regenerative body wall and intestine of A. japonicus. The database has increased to ~30000 ESTs. RESULTS: We used RNA-Seq to determine gene expression profiles associated with intestinal regeneration in A. japonicus at 3, 7, 14 and 21 days post evisceration (dpe. This was compared to profiles obtained from a normally-functioning intestine. Approximately 5 million (M reads were sequenced in every library. Over 2400 up-regulated genes (>10% and over 1000 down-regulated genes (~5% were observed at 3 and 7dpe (log2Ratio ≥ 1, FDR ≤ 0.001. Specific "Go terms" revealed that the DEGs (Differentially Expressed Genes performed an important function at every regeneration stage. Besides some expected pathways (for example, Ribosome and Spliceosome pathway term, the "Notch signaling pathway," the "ECM-receptor interaction" and the "Cytokine-cytokine receptor interaction" were significantly enriched. We also investigated the expression profiles of developmental genes, ECM-associated genes and Cytoskeletal genes. Twenty of the most important differentially expressed genes (DEGs were verified by Real-time PCR, which resulted in a trend concordance of almost 100% between the two techniques. CONCLUSION: Our studies demonstrated dynamic changes in global gene expression during intestine regeneration and presented a series of candidate genes and enriched
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A. ZENETOS
2005-12-01
Full Text Available This collaborative effort by many specialists across the Mediterranean presents an updated annotated list of alien marine species in the Mediterranean Sea. Alien species have been grouped into six broad categories namely established, casual, questionable, cryptogenic, excluded and invasive, and presented in lists of major ecofunctional/taxonomic groups. The establishment success within each group is provided while the questionable and excluded records are commented in brief. A total of 963 alien species have been reported from the Mediterranean until December 2005, 218 of which have been classified as excluded (23% leaving 745 of the recorded species as valid aliens. Of these 385 (52% are already well established, 262 (35% are casual records, while 98 species (13% remain “questionable” records. The species cited in this work belong mostly to zoobenthos and in particular to Mollusca and Crustacea, while Fish and Phytobenthos are the next two groups which prevail among alien biota in the Mediterranean. The available information depends greatly on the taxonomic group examined. Thus, besides the three groups explicitly addressed in the CIESM atlas series (Fish, Decapoda/Crustacea and Mollusca, which are however updated in the present work, Polychaeta, Phytobenthos, Phytoplankton and Zooplankton are also addressed in this study. Among other zoobenthic taxa sufficiently covered in this study are Echinodermata, Sipuncula, Bryozoa and Ascidiacea. On the contrary, taxa such as Foraminifera, Amphipoda and Isopoda, that are not well studied in the Mediterranean, are insufficiently covered. A gap of knowledge is also noticed in Parasites, which, although ubiquitous and pervasive in marine systems, have been relatively unexplored as to their role in marine invasions. Conclusively the lack of funding purely systematic studies in the region has led to underestimation of the number of aliens in the Mediterranean. Emphasis is put on those species that are
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Carolina Doya
Full Text Available Knowledge of the processes shaping deep-sea benthic communities at seasonal scales in cold-seep environments is incomplete. Cold seeps within highly dynamic regions, such as submarine canyons, where variable current regimes may occur, are particularly understudied. Novel Internet Operated Vehicles (IOVs, such as tracked crawlers, provide new techniques for investigating these ecosystems over prolonged periods. In this study a benthic crawler connected to the NEPTUNE cabled infrastructure operated by Ocean Networks Canada was used to monitor community changes across 60 m2 of a cold-seep area of the Barkley Canyon, North East Pacific, at ~890 m depth within an Oxygen Minimum Zone (OMZ. Short video-transects were run at 4-h intervals during the first week of successive calendar months, over a 14 month period (February 14th 2013 to April 14th 2014. Within each recorded transect video megafauna abundances were computed and changes in environmental conditions concurrently measured. The responses of fauna to environmental conditions as a proxy of seasonality were assessed through analysis of abundances in a total of 438 video-transects (over 92 h of total footage. 7698 fauna individuals from 6 phyla (Cnidaria, Ctenophora, Arthropoda, Echinodermata, Mollusca, and Chordata were logged and patterns in abundances of the 7 most abundant taxa (i.e. rockfish Sebastidae, sablefish Anoplopoma fimbria, hagfish Eptatretus stoutii, buccinids (Buccinoidea, undefined small crabs, ctenophores Bolinopsis infundibulum, and Scyphomedusa Poralia rufescens were identified. Patterns in the reproductive behaviour of the grooved tanner crab (Chionnecetes tanneri were also indicated. Temporal variations in biodiversity and abundance in megabenthic fauna was significantly influenced by variabilities in flow velocity flow direction (up or down canyon, dissolved oxygen concentration and month of study. Also reported here for the first time are transient mass aggregations of
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Collard, Marie; De Ridder, Chantal; David, Bruno; Dehairs, Frank; Dubois, Philippe
2015-02-01
Increasing atmospheric carbon dioxide concentration alters the chemistry of the oceans towards more acidic conditions. Polar oceans are particularly affected due to their low temperature, low carbonate content and mixing patterns, for instance upwellings. Calcifying organisms are expected to be highly impacted by the decrease in the oceans' pH and carbonate ions concentration. In particular, sea urchins, members of the phylum Echinodermata, are hypothesized to be at risk due to their high-magnesium calcite skeleton. However, tolerance to ocean acidification in metazoans is first linked to acid-base regulation capacities of the extracellular fluids. No information on this is available to date for Antarctic echinoderms and inference from temperate and tropical studies needs support. In this study, we investigated the acid-base status of 9 species of sea urchins (3 cidaroids, 2 regular euechinoids and 4 irregular echinoids). It appears that Antarctic regular euechinoids seem equipped with similar acid-base regulation systems as tropical and temperate regular euechinoids but could rely on more passive ion transfer systems, minimizing energy requirements. Cidaroids have an acid-base status similar to that of tropical cidaroids. Therefore Antarctic cidaroids will most probably not be affected by decreasing seawater pH, the pH drop linked to ocean acidification being negligible in comparison of the naturally low pH of the coelomic fluid. Irregular echinoids might not suffer from reduced seawater pH if acidosis of the coelomic fluid pH does not occur but more data on their acid-base regulation are needed. Combining these results with the resilience of Antarctic sea urchin larvae strongly suggests that these organisms might not be the expected victims of ocean acidification. However, data on the impact of other global stressors such as temperature and of the combination of the different stressors needs to be acquired to assess the sensitivity of these organisms to global
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Patrícia P. Silva
2012-12-01
Full Text Available Este estudo teve como objetivos descrever o ciclo gametogênico e o comportamento reprodutivo da população de Iphigenia brasiliana (Lamarck,1818 no estuário do rio Subaé, Baía de Todos os Santos, Bahia. Os bivalves foram coletados de novembro de 2001 a novembro de 2002. Um total de 244 espécimes foi medido (eixo anteroposterior, eviscerado, fixado, desidratado e incluído em parafina. O estudo histológico das gônadas foi realizado através de cortes seriados do tecido gonadal, de 5 mm de espessura, e corados pela HE. O tamanho médio mínimo da primeira maturação sexual (Lpm foi estimado a partir da distribuição das frequências relativas de jovens e adultos, por classe de comprimento dos indivíduos. As frequências relativas dos sexos em cada estádio de desenvolvimento foram consideradas conjuntamente para a análise do comportamento reprodutivo da população, e, em separado, para avaliar a sincronia do ciclo sexual entre machos e fêmeas. Foi observada uma variação de tamanhos entre 9,1 e 66,6 mm, com comprimento médio de 50,2 mm. O estudo não demonstrou diferença significativa entre os tamanhos de machos e fêmeas. Não foi possível observar a diferenciação de sexos em 2,1% dos indivíduos analisados. 51,6% dos indivíduos foram identificados como machos (M e 46,3% como fêmeas (F, não sendo constatadas diferenças significativas entre o número médio de machos e fêmeas, resultando numa proporção de M:F de 1,1:1. O Lpm foi estimado em 11,4 mm, mas apenas ao alcançarem comprimento médio de 34,4 mm, todos os indivíduos foram considerados adultos. Foram caracterizados quatro estádios de evolução do desenvolvimento gonadal em fêmeas e machos. A análise dos diferentes estádios permitiu a observação dos fenômenos de atresia e inversão sexual em fêmeas. O ciclo reprodutivo apresentou eliminação contínua de gametas, com maiores intensidades reprodutivas nos meses de novembro de 2001 a abril de 2002 e, tamb
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Directory of Open Access Journals (Sweden)
Patrícia P. Silva
2012-01-01
Full Text Available Este estudo teve como objetivos descrever o ciclo gametogênico e o comportamento reprodutivo da população de Iphigenia brasiliana (Lamarck,1818 no estuário do rio Subaé, Baía de Todos os Santos, Bahia. Os bivalves foram coletados de novembro de 2001 a novembro de 2002. Um total de 244 espécimes foi medido (eixo anteroposterior, eviscerado, fixado, desidratado e incluído em parafina. O estudo histológico das gônadas foi realizado através de cortes seriados do tecido gonadal, de 5 mm de espessura, e corados pela HE. O tamanho médio mínimo da primeira maturação sexual (Lpm foi estimado a partir da distribuição das frequências relativas de jovens e adultos, por classe de comprimento dos indivíduos. As frequências relativas dos sexos em cada estádio de desenvolvimento foram consideradas conjuntamente para a análise do comportamento reprodutivo da população, e, em separado, para avaliar a sincronia do ciclo sexual entre machos e fêmeas. Foi observada uma variação de tamanhos entre 9,1 e 66,6 mm, com comprimento médio de 50,2 mm. O estudo não demonstrou diferença significativa entre os tamanhos de machos e fêmeas. Não foi possível observar a diferenciação de sexos em 2,1% dos indivíduos analisados. 51,6% dos indivíduos foram identificados como machos (M e 46,3% como fêmeas (F, não sendo constatadas diferenças significativas entre o número médio de machos e fêmeas, resultando numa proporção de M:F de 1,1:1. O Lpm foi estimado em 11,4 mm, mas apenas ao alcançarem comprimento médio de 34,4 mm, todos os indivíduos foram considerados adultos. Foram caracterizados quatro estádios de evolução do desenvolvimento gonadal em fêmeas e machos. A análise dos diferentes estádios permitiu a observação dos fenômenos de atresia e inversão sexual em fêmeas. O ciclo reprodutivo apresentou eliminação contínua de gametas, com maiores intensidades reprodutivas nos meses de novembro de 2001 a abril de 2002 e, tamb
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Del mecanicismo a la complejidad en la biología
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Libia Herrero Uribe
2008-03-01
Full Text Available A través de la historia, los organismos vivos han sido estudiados desde diferentes puntos de vista. Presento tres etapas, la primera totalmente ligada al ambiente que rodea al ser humano, la segunda que se basa en las leyes de la química y la física, y la tercera que es integral o sistémica. Tras pasar revista a los grandes descubrimientos de los humanos primitivos hasta el descubrimiento del ADN y el inicio del reduccionismo en la ciencia,propongo la calidad paradójica de los organismos vivos, que obedecen a las leyes de la física y la química, pero que, creo, no pueden ser explicados en términos de esas ciencias. Analizo las teorías de sistemas y autopoiesis, las estructuras disipativas y la matemática no linear, para afirmar que el paradigma de la naturaleza determinista, lineal y cuantitativa debe dejarse de lado como la única forma de estudiar los organismos vivos e invitarle a explorar el paradigma de la complejidad.From the mechanical complexity in biology. Through history, each century has brought new discoveries and beliefs that have resulted in different perspectives to study life organisms. In this essay, I define three periods: in the first, organisms were studied in the context of their environment, in the second, on the basis of physical and chemical laws, and on the third, systemically. My analysis starts with primitive humans, continues to Aristoteles and Newton, Lamarck and Darwin, the DNA doble helix discovery, and the beginnings of reduccionism in science. I propose that life is paradigmatical, that it obeys physical and chemical laws but cannot be explained by them I review the systemic theory, autopoiesis, discipative structures and non- linear dynamics. I propose that the deterministic, lineal and quantitative paradigm of nature are not the only way to study nature and invite the reader to explore the complexity paradigm. Rev. Biol. Trop. 56 (1: 399-407. Epub 2008 March 31.
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González-Trujano, María Eva; Martínez-González, Claudia Lizbeth; Flores-Carrillo, Maricela; Luna-Nophal, Sara Ibeth; Contreras-Murillo, Gerardo; Magdaleno-Madrigal, Víctor Manuel
2018-01-15
Moringa oleifera Lamarck is a species that has long been used in high demand in folk medicine, including for the treatment of epilepsy. Nevertheless, scientific studies demonstrating its anticonvulsant properties and the nature of the bioactive constituents are lacking. The aim of this study was to evaluate the anticonvulsant activities of the Moringa oleifera leaves in non-polar vs. polar extracts using behavioral and electroencephalographic (EEG) analyses in rodents. First, PTZ (80 mg/kg, i.p.)-induced tonic-clonic seizures were assayed via a dose-response (100, 200 and 300 mg/kg, i.p.) evaluation in mice. Then, a dosage of the extracts (100 or 300 mg/kg) and one metabolite (30 mg/kg, i.p.) was selected to evaluate its effect on PTZ (35 mg/kg, i.p.)-induced EEG paroxystic activities in rats compared to the effects of ethosuximide (reference anticonvulsant drug, 100 mg/kg, i.p.). Latent onset of the first paroxystic spike, first seizure and frequency as well as seizure severity, were determined using Racine's scale. Moringa oleifera ethanol and hexane extracts produced a delay in the seizure latency in mice and rats; this effect was improved in the presence of the hexane extract containing the active metabolite hexadecanoic acid. The anticonvulsant effects were corroborated in the spectral analysis by the potency of the EEG due to a reduction in the spike frequency and amplitude, as well as in the duration and severity of the seizures. The effects of the hexane extract resembled those observed in the reference antiepileptic drug ethosuximide. Moringa oleifera leaves possess anticonvulsant activities due to the complementary of the non-polar and polar constituents. However, the non-polar constituents appear to exert an important influence via the partial participation of fatty acids, providing evidence of the effects of this plant in epilepsy therapy. Copyright © 2017. Published by Elsevier GmbH.
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Muzitano, Michelle F; Bergonzi, Maria Camilla; De Melo, Giany O; Lage, Celso L S; Bilia, Anna Rita; Vincieri, Franco F; Rossi-Bergmann, Bartira; Costa, Sônia S
2011-01-07
Leaves from Kalanchoe pinnata (Lamarck) Persoon (Crassulaceae) are popularly used for healing wounds. Its antileishmanial properties are established in experimental animals, and its active flavonoid components have been identified. In this study, we attempted to standardize the extract from K. pinnata leaves by evaluating the influence of season of harvest, sunlight exposure and method of extraction on antileishmanial flavonoids content. HPLC-DAD-MS was used to identify and quantify the active antileishmanial flavonoids in different extracts. ANOVA test for analyses of variance followed by the Tukey test of multiple comparisons were used in the statistical analysis. The antileishmanial potential was assessed by the activation of nitric oxide production by murine macrophage using the Griess method. We demonstrated that active flavonoids were significantly more abundant when the leaves were collected in the summer, and that aqueous extraction at 50°C allowed the highest flavonoid extraction. The benefit of sunlight exposure was confirmed in plants cultivated under direct sunlight when compared with those that grown under shade. Under sunny conditions the yield of the most active antileishmanial favonoid quercitrin was increased by 7-fold. All aqueous extracts tested were capable to enhance the macrophage nitric oxide production. However, hot aqueous extract from leaves collected in summer exhibited the higher activity, in agreement with HPLC-DAD-MS analysis tendency. In addition, with the aim of reducing the individual chemical variations of the plant constituents and optimizing the production of the active extract, it was obtained in vitro monoclonal KP specimens that were easily adapted to field conditions and were able to produce antileishmanial flavonoids. Our study reports the better conditions of cultivation, harvest and extraction protocol for obtaining a K. pinnata extract exhibiting the highest antileishmanial activity. Additionally, we propose the
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Way, M J; Heong, K L
2009-10-01
The tropical fire ant Solenopsis geminata (Fabricius) often nests very abundantly in the earthen banks (bunds) around irrigated rice fields in the tropics. Where some farmers habitually drain fields to the mud for about 3-4 days, the ants can quickly spread up to about 20 m into the fields where they collect food, including pest prey such as the eggs and young of the apple snail Pomacea caniculata (Lamarck) and insects such as lepidopterous larvae and hoppers, notably Nilaparvata lugens (Stäl) the brown planthopper (Bph) and green leafhoppers Nephotettix spp. Even in drained fields, the activity of S. geminata is restricted by rainfall in the wet season. The relatively few ant workers that forage characteristically into drained fields and on to the transplanted clumps of rice plants (hills) kill the normally few immigrant Bph adults but are initially slower acting than other species of the natural enemy complex. However, larger populations of Bph are fiercely attacked and effectively controlled by rapidly recruited ant workers; whereas, in the absence of the ant, the other natural enemies are inadequate. In normal circumstances, there is no ant recruitment in response to initially small populations of immigrant Bph and no evidence of incompatibility between ant foragers and other natural enemies such as spiders. However, when many ants are quickly and aggressively recruited to attack large populations of Bph, they temporarily displace some spiders from infested hills. It is concluded that, in suitable weather conditions and even when insecticides kill natural enemies within the rice field, periodic drainage that enables S. geminata to join the predator complex is valuable for ant-based control of pests such as snails and Lepidoptera, and especially against relatively large populations of Bph. Drainage practices to benefit ants are fully compatible with recent research, which shows that periodic drainage combats problems of 'yield decline' in intensively irrigated
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[Historic and functional biology: the inadequacy of a system theory of evolution].
Regelmann, J P
1982-01-01
In the first half of the 20th century neo-Kantianism in a broad sense proved itself the main conceptual and methodological background of the central European biology. As such it contributed much to the victory on the typological, idealistic-morphological and psycho-vitalistic interpretations of life. On the other hand it could not give tools to the biologists for working out a strictly darwinian evolution theory. Kant's theory of organism was conceived without evolution as a theory of the internal functionality of the organism. There was only some 'play' with the evolutionary differentiation of the species. Since then the disputes around the work of August Weismann, a synthetical evolution theory which is now behind time, arose. This theory developed from coinciding claims, elaborated by geneticists, mathematicians, and by biologists studying development, natural history and systematics. This was done under a strong influence of marxist ideas. Through the interweaving of such different approaches it was possible for this evolutionary synthesis to influence successfully the development of evolution research during more than 40 years. Philosophically speaking modern evolution theory means therefore an aversion, even a positive abolition of Kantian positions. A number of biologists however--as L. von Bertalanffy--refused to adhere to a misinterpreted Kantian methodology and oriented themselves to an approach via system theory, which obtained a place in evolution research. In fact this is a Kantian approach as well. They only repeated the Kantian dilemma of the evolution which can also be found in Lamarck and Hegel. The system theory of the functionality of the organism never reaches to the level of the evolving species, but remains always on the level of epigenetic thinking, because of its philosophical origin. This paper points out the consequences of this still current dilemma. At the same time an all-enclosing reflection on the methodological, epistemological and
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Directory of Open Access Journals (Sweden)
Graciela S Diniz
2014-05-01
Full Text Available The chemical profiles of Desmapsamma anchorata, Hymeniacidon heliophila (Porifera, Bunodosoma caissarum, Renilla muelleri (Cnidaria, Aplysia brasiliana, Eledone massyae, Isognomon bicolor (Mollusca, Echinaster brasiliensis, Echinometra lucunter, Holothuria grisea, Lytechinus variegatus (Echinodermata, and Phallusia nigra (Chordata were determined. Hydrosoluble protein was the most abundant class of substances for all species, except for the ascidian Phallusia nigra, in which the carbohydrate content was higher. The percentages of hydrosoluble protein (dry weight, dw varied widely among the invertebrates, ranging from 5.88% (R. muelleri to 47.6% (Eledone massyae of the dw .The carbohydrate content fluctuated from 1.3% (R. muelleri to 18.4% (Aplysia brasiliana of the dw. For most of the species, lipid was the second most abundant class of substances, varying from 2.8% (R. muelleri to 25.3% (Echinaster brasiliensis of the dw. Wide variations were also found for the invertebrates nitrogen content, with the lowest value recorded in the cnidarian R. muelleri (2.02% of the dw and the highest in the molluscan E. massyae (12.7% of the dw. The phosphorus content of the dw varyed from 0.24% (R. muelleri to 1.16% (E. massyae. The amino acid composition varied largely among the species, but for most of the species glycine, arginine, glutamic acid, and aspartic acid were the most abundant amino acids, with histidine and tyrosine among the less abundant amino acids. The actual content of total protein in the samples was calculated by the sum of amino acid residues, establishing dw values that fluctuated from 11.1% (R. muelleri to 66.7% (E. massyae. The proteinaceous nitrogen content was high in all species, with an average value of 97.3% of the total nitrogen. From data of total amino acid residues and total nitrogen, specific nitrogen-to-protein conversion factors were calculated for each species. The nitrogen-to-protein conversion factors ranged from 5.10 to
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Tatiana D Mayorova
2016-12-01
Full Text Available Neuropeptides are an ancient class of neuronal signaling molecules that regulate a variety of physiological and behavioral processes in animals. The life cycle of many animals includes a larval stage(s that precedes metamorphic transition to a reproductively active adult stage but, with the exception of Drosophila melanogaster and other insects, research on neuropeptide signaling has hitherto largely focused on adult animals. However, recent advances in genome/transcriptome sequencing have facilitated investigation of neuropeptide expression/function in the larvae of protostomian (e.g. the annelid Platynereis dumerilii and deuterostomian (e.g. the urochordate Ciona intestinalis invertebrates. Accordingly, here we report the first multi-gene investigation of larval neuropeptide precursor expression in a species belonging to the phylum Echinodermata - the starfish Asterias rubens. Whole-mount mRNA in situ hybridization was used to visualize in bipinnaria and brachiolaria stage larvae the expression of eight neuropeptide precursors: L-type SALMFamide (S1, F-type SALMFamide (S2, vasopressin/oxytocin-type, NGFFYamide, thyrotropin-releasing hormone-type, gonadotropin-releasing hormone-type, calcitonin-type and corticotropin-releasing hormone-type. Expression of only three of the precursors (S1, S2, NGFFYamide was observed in bipinnaria larvae but by the brachiolaria stage expression of all eight precursors was detected. An evolutionarily conserved feature of larval nervous systems is the apical organ and in starfish larvae this comprises the bilaterally symmetrical lateral ganglia, but only the S1 and S2 precursors were found to be expressed in these ganglia. A prominent feature of brachiolaria larvae is the attachment complex, comprising the brachia and adhesive disk, which mediates larval attachment to a substratum prior to metamorphosis. Interestingly, all of the neuropeptide precursors examined here are expressed in the attachment complex, with
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Bruno P. Masi
2008-12-01
Full Text Available O presente estudo pretende comparar a distribuição vertical da comunidade bêntica na zona entremarés em dois locais compostos por matacões graníticos caracterizados por hidrodinâmica distinta, reflexo da diferença na orientação dos molhes nas praias do Farol de São Tomé (Píer e na Barra do Furado (Barra, norte do Estado do Rio de Janeiro. Quadrados de 400 cm² foram sobrepostos ao longo de três perfis verticais de ambos os sítios e amostrados através do método de fotoquadrats, desde o nível 0,2 m da maré até o limite superior de Littorina spp. O limite superior dos organismos marinhos foi ampliado na Barra (3,8 m em relação ao Píer (2,2 m. Quanto à composição taxonômica, nove espécies foram comuns. Chaetomorpha sp., Chondracanthus teedii (Mertens ex Roth Fredericq e Grateloupia sp. foram exclusivas na Barra, enquanto Tetraclita stalactifera (Lamarck, 1818, Fissurella clench, Gracilaria domingensis (Kützing Sonder ex Dickie e Hypnea musciformis (Wulfen in Jacqu. Lamouroux ocorreram somente no Píer. Em ambos os locais, a riqueza e a diversidade de espécies foram superiores nos quadrados intermediários. Os maiores valores foram registrados na Barra. As maiores diferenças nos agrupamentos entre faixas equivalentes de locais distintos ocorreram na faixa eulitorânea superior, seguida pela faixa eulitorânea inferior e franja sublitorânea. Apenas a orla litorânea não revelou diferença significativa entre os locais, mas uma maior extensão desta franja e da faixa eulitorânea superior era bastante evidente. As demais faixas na Barra do Furado foram caracterizadas em grande parte por espécies típicas de ambientes mais expostos como Chaetomorpha sp. na faixa eulitorânea superior e Perna perna (Linnaeus, 1758 na eulitorânea inferior, além de C. teedii e Ulva fasciata Delile, 1813 na franja sublitorânea. No Píer, as diferentes faixas apresentavam distribuição eqüitativa, refletindo um ambiente menos
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R. Saravanan
2015-08-01
Full Text Available The association of Parthenopid crab Zebrida adamsii and flower urchin Toxopneustes pileolus is reported for the first time from Gulf of Mannar. The Parthenopid crab Zebrida adamsii has been found to be associated exclusively with these sea urchins and this obligatory association has been studied by introducing another host sea urchin Salmacis virgulata to understand host preferences.
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From the scala naturae to the symbiogenetic and dynamic tree of life
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Kutschera Ulrich
2011-06-01
Full Text Available Abstract All living beings on Earth, from bacteria to humans, are connected through descent from common ancestors and represent the summation of their corresponding, ca. 3500 million year long evolutionary history. However, the evolution of phenotypic features is not predictable, and biologists no longer use terms such as "primitive" or "perfect organisms". Despite these insights, the Bible-based concept of the so-called "ladder of life" or Scala Naturae, i.e., the idea that all living beings can be viewed as representing various degrees of "perfection", with humans at the very top of this biological hierarchy, was popular among naturalists until ca. 1850 (Charles Bonnet, Jean Lamarck and others. Charles Darwin is usually credited with the establishment of a branched evolutionary "Tree of Life". This insight of 1859 was based on his now firmly corroborated proposals of common ancestry and natural selection. In this article I argue that Darwin was still influenced by "ladder thinking", a theological view that prevailed throughout the 19th century and is also part of Ernst Haeckel's famous Oak tree (of Life of 1866, which is, like Darwin's scheme, static. In 1910, Constantin Mereschkowsky proposed an alternative, "anti-selectionist" concept of biological evolution, which became known as the symbiogenesis-theory. According to the symbiogenesis-scenario, eukaryotic cells evolved on a static Earth from archaic prokaryotes via the fusion and subsequent cooperation of certain microbes. In 1929, Alfred Wegener published his theory of continental drift, which was later corroborated, modified and extended. The resulting theory of plate tectonics is now the principal organizing concept of geology. Over millions of years, plate tectonics and hence the "dynamic Earth" has caused destructive volcanic eruptions and earthquakes. At the same time, it created mountain ranges, deep oceans, novel freshwater habitats, and deserts. As a result, these geologic
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Lower Oligocene bivalves of Ramanian Stage from Kachchh, Gujarat, India
Kachhara, R. P.; Jodhawat, R. L.; Devi, K. Bigyapati
2012-04-01
Marine Oligocene sequences in India outcrop only in western part of Kachchh. Earlier researchers have recognized the Oligocene strata under the Nari Series (Nagappa 1959; Chatterji and Mathur 1966). The Nari Series has a type area in Pakistan. It has two subdivisions - the Lower Nari (Lower Oligocene) and the Upper Nari (Upper Oligocene). It seems that there is no valid proof about the age of the Lower Nari due to lack of proper fauna (Eames 1975), and according to Pascoe (1962), the Upper Nari slightly transgress into Aquitanian (Lower Miocene), therefore, one has to be very cautious. Biswas and Raju (1971) reclassified the Oligocene strata of Kachchh and lithostratigraphically clubbed them as the Maniyara Fort Formation with type section along the Bermoti stream. This Formation has four members. The lower three members correspond to the Ramanian Stage (Lower Oligocene, Biswas 1971, 1973) while the uppermost to the Waiorian Stage (Upper Oligocene, Biswas 1965, 1971, 1973). The Ramanian Stage is characterized by large forams especially Nummulites fichteli, Nummulites fichteli intermedius, Lepidocyclina ( Eulepidina) dialata and Operculina sp. Several ostracods are also known to occur. Megafauna include bivalves, gastropods, echinoids, corals, mammals and reptiles. Concerning bivalves earlier researchers have recorded a few taxa namely Trisidos semitorta (Lamarck), Cubitostrea angulata (J de C Sowerby), Pecten ( Amussiopecten) labadyei d'Archiac and Haime, Periglypta puerpera (Linne') var. aglaurae Brongniart, Ostrea fraasi Mayer Eymer and listed Pecten laevicostatus J de C Sowerby, Callista pseudoumbonella Vredenburg and Clementia papyracea (Gray) from Kachchh as against overall 42 forms from the Nari Series as a whole (Vredenburg 1928). This tempted us to make an attempt to collect bivalve fauna systematically which are occurring prolifically in the Ramanian Stage. In the present work, for this purpose, sections are worked out around Lakhpat (23°50'N; 68°47'E
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Trees and networks before and after Darwin
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Ragan Mark A
2009-11-01
Full Text Available Abstract It is well-known that Charles Darwin sketched abstract trees of relationship in his 1837 notebook, and depicted a tree in the Origin of Species (1859. Here I attempt to place Darwin's trees in historical context. By the mid-Eighteenth century the Great Chain of Being was increasingly seen to be an inadequate description of order in nature, and by about 1780 it had been largely abandoned without a satisfactory alternative having been agreed upon. In 1750 Donati described aquatic and terrestrial organisms as forming a network, and a few years later Buffon depicted a network of genealogical relationships among breeds of dogs. In 1764 Bonnet asked whether the Chain might actually branch at certain points, and in 1766 Pallas proposed that the gradations among organisms resemble a tree with a compound trunk, perhaps not unlike the tree of animal life later depicted by Eichwald. Other trees were presented by Augier in 1801 and by Lamarck in 1809 and 1815, the latter two assuming a transmutation of species over time. Elaborate networks of affinities among plants and among animals were depicted in the late Eighteenth and very early Nineteenth centuries. In the two decades immediately prior to 1837, so-called affinities and/or analogies among organisms were represented by diverse geometric figures. Series of plant and animal fossils in successive geological strata were represented as trees in a popular textbook from 1840, while in 1858 Bronn presented a system of animals, as evidenced by the fossil record, in a form of a tree. Darwin's 1859 tree and its subsequent elaborations by Haeckel came to be accepted in many but not all areas of biological sciences, while network diagrams were used in others. Beginning in the early 1960s trees were inferred from protein and nucleic acid sequences, but networks were re-introduced in the mid-1990s to represent lateral genetic transfer, increasingly regarded as a fundamental mode of evolution at least for
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From the scala naturae to the symbiogenetic and dynamic tree of life.
Kutschera, Ulrich
2011-06-30
All living beings on Earth, from bacteria to humans, are connected through descent from common ancestors and represent the summation of their corresponding, ca. 3500 million year long evolutionary history. However, the evolution of phenotypic features is not predictable, and biologists no longer use terms such as "primitive" or "perfect organisms". Despite these insights, the Bible-based concept of the so-called "ladder of life" or Scala Naturae, i.e., the idea that all living beings can be viewed as representing various degrees of "perfection", with humans at the very top of this biological hierarchy, was popular among naturalists until ca. 1850 (Charles Bonnet, Jean Lamarck and others). Charles Darwin is usually credited with the establishment of a branched evolutionary "Tree of Life". This insight of 1859 was based on his now firmly corroborated proposals of common ancestry and natural selection. In this article I argue that Darwin was still influenced by "ladder thinking", a theological view that prevailed throughout the 19th century and is also part of Ernst Haeckel's famous Oak tree (of Life) of 1866, which is, like Darwin's scheme, static. In 1910, Constantin Mereschkowsky proposed an alternative, "anti-selectionist" concept of biological evolution, which became known as the symbiogenesis-theory. According to the symbiogenesis-scenario, eukaryotic cells evolved on a static Earth from archaic prokaryotes via the fusion and subsequent cooperation of certain microbes. In 1929, Alfred Wegener published his theory of continental drift, which was later corroborated, modified and extended. The resulting theory of plate tectonics is now the principal organizing concept of geology. Over millions of years, plate tectonics and hence the "dynamic Earth" has caused destructive volcanic eruptions and earthquakes. At the same time, it created mountain ranges, deep oceans, novel freshwater habitats, and deserts. As a result, these geologic processes destroyed numerous
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Is metal pollution a threat to the continued survival of the starfish in False Bay, South Africa?
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Adriaan J. Reinecke
2013-02-01
Full Text Available Urbanisation and industrial development in the catchment area of False Bay in South Africa are increasing and concern was raised about the effect of environmental pollutants on intertidal fauna such as starfish. The aim of the present study was to obtain initial descriptive baseline data over several seasons during 2000–2001 of metal concentrations in water, sediment and body samples of the chosen cushion starfish Parvulastra exigua (Lamarck, 1816 that occurs widely in the intertidal zone of False Bay. Concentrations of cadmium, copper, lead, nickel and zinc were measured in samples of the cushion starfish, water and sediment at five localities along the coast of False Bay. The samples were chemically analysed for metals by atomic spectrophotometry. The highest individually measured concentrations of cadmium (Cd in starfish and sediment were found in the northern coastal region between Strand and Muizenberg where most industrial activity and human settlement occur. Large variation in concentrations of all metals occurred between localities and seasons. The mean concentrations of Cd and Pb in water and sediment were in a few instances slightly higher than the recommended levels or target values of the South African marine water and sediment quality norms but still lower than those in various developed countries. Indications are that the bay was at the time of this study still less contaminated by metals in comparison with the coastal waters of various other countries. The accumulation of nonessential metals such as cadmium and lead in both sediment and bodies of starfish was nevertheless such that it can be assumed that environmental concentrations in some parts of the bay could over time build up to levels that are detrimental to the species as well as their predators. This study provided evidence that the cushion starfish in False Bay is exposed to several metals of which some are potentially hazardous since they tend to gradually accumulate
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Bellas, Juan; Beiras, Ricardo; Mariño-Balsa, José Carlos; Fernández, Nuria
2005-04-01
This study investigated the toxic effects of the insecticides lindane and chlorpyrifos, the herbicide diuron, the organometallic antifoulant tributyltin (TBT), and the surfactant sodium dodecyl sulfate (SDS) on the early life stages of Paracentrotus lividus (Echinodermata, Euechinoidea), Ciona intestinalis (Chordata, Ascidiacea), Maja squinado and Palaemon serratus (Arthropoda, Crustacea) in laboratory acute toxicity tests. The assays studied embryogenesis success from fertilized egg to normal larvae in P. lividus (48 h incubation at 20 degrees C) and C. intestinalis (24 h incubation at 20 degrees C), and larval mortality at 24 and 48 h in M. squinado and P. serratus. For P. lividus, the median effective concentrations (EC50) reducing percentages of normal larvae by 50% were: 350 microg l(-1) for chlorpyrifos, 5500 microg l(-1) for diuron, 4277 microg l(-1) for SDS, and 0.309 microg l(-1) for TBT. For C. intestinalis, the EC50 values affecting embryogenesis success were 5666 microg l(-1) for chlorpyrifos, 24,397 microg (l-1) for diuron, 4412 microg l(-1) for lindane, 5145 microg I(-1) for SDS, and 7.1 microg l(-1) for TBT. The median lethal concentrations (LC50) for M. squinado larval survival were 0.84 microg l(-1) (24 h) and 0.79 microg l(-1) (48 h) for chlorpyrifos, 2.23 microg(l(-1) (24 h) and 2.18 microg l(-1) (48 h) for lindane, and 687 microg l(-1) (48 h) for SDS. For P. serratus the LC50 values obtained were 0.35 microg l(-1) (24 h) and 0.22 microg l(-1) (48 h) for chlorpyrifos, 3011 microg l(-1) (24 h) and 3044 microg l(-1) (48 h) for diuron, 5.20 microg l(-1) (24 h) and 5.59 microg l(-1) (48 h) for lindane, and 22.30 microg l(-1) (24 h) and 17.52 microg l(-1) (48 h) for TBT. Decapod larvae, as expected, were markedly more sensitive to the insecticides than sea urchins and ascidians, and SDS was the least toxic compound tested for these organisms. Lowest observed effect concentrations (LOEC) of TBT for sea urchin and ascidian embryos, chlorpyrifos and
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Cláudia T. Callil
2007-01-01
Full Text Available O ciclo reprodutivo de Anodontites trapesialis foi estudado entre os meses de maio de 1998 a abril de 1999. Análises quantitativas dos elementos celulares revelaram que a espécie é exclusivamente hermafrodita com folículos masculinos e femininos separados. A gametogênese é contínua com picos de maturação e eliminação de gametas durante a estação seca. A ovogênese tem seu período de maturação máxima em abril e maio, momento em que óvulos maduros são observados preenchendo os folículos e gonoductos. A espermatogênese foi reconhecida por uma fase proliferativa com células em desenvolvimento e apresentou seu período de maturação entre abril e julho. Estas células se diferenciaram dando origem às mórulas espermáticas e espermatozóides livres, organizando a série espermática radial. Durante o período de liberação dos gametas, a maioria dos folículos apresentou agregados de espematozóides formando esferas espermáticas as "spermballs", as quais caracterizam a espécie como espermatozeugmata.The reproductive cycle of Anodontites trapesialiswas studied from May 1998 to April 1999. Quantitative analysis of the sexual cycle revealed that the species is exclusively hermaphrodite with separate male and female follicles. Gametogenesis is continuous with peaks of maturation and elimination of gametes during dry season. The period of maximum maturation of the oogenesis was in April and May, when mature oocytes were observed filling the follicles and gonoducts. Spermatogenesis was recognized by a proliferation phase with developing cells with period of maturation since April to July. These cells started to differentiate giving origin to spermatic morulae and free spermatozoa organizing the radial spermatic series. During the period of discharge of the gamets, the majority of follicles presented aggregates of spermatozoa forming the spermballs, which characterize the species as spermatozeugmata.
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Batten, D J.; Collinson, M E.
2001-05-01
Species of the megaspore genus Minerisporites Potonié, megaspore apparatuses of species of the water fern Azolla Lamarck, and some associated organic-walled microfossils recovered from deposits of the Upper Palaeocene and Palaeocene/Eocene transition in the southern part of the Netherlands and neighbouring Belgium are redescribed on the basis of an examination of specimens under scanning and transmission electron microscopes. Originally studied about 40 years ago by S.J. Dijkstra, the re-examination has enabled emended diagnoses to be produced for six taxa: Minerisporites glossoferus (Dijkstra) Tschudy, M. mirabilis (Miner) Potonié, M. mirabilissimus (Dijkstra) Potonié, Azolla schopfii Dijkstra, A. teschiana Florschütz, and A. velus (Dijkstra) Jain and Hall. In addition, a revised description is provided for massulae of Salvinia Séguier that were originally thought to be megaspores and, hence, named by Dijkstra as Triletes? exiguus. The gross morphology and construction of the exospore of the species of Minerisporites are similar, but nevertheless sufficiently distinct for them to be maintained as separate taxa. Monolete microspores are preserved in hollows in the reticulate surface of some of the specimens of M. mirabilissimus. This is consistent with the presumed isoetalean affinity of Minerisporites. An apparent stratigraphic morphocline from M. glossoferus to M. mirabilis, suggested previously, is confirmed following our reassessment of their characteristics. The species of Azolla are all multi-floated, but they differ from each other in several ways, in particular with respect to the ultrastructure of the megaspore wall. They are also distinct from all other species that have been considered in sufficient detail for satisfactory comparisons to be made. The massulae of A. teschiana are described for the first time. The floats in A. velus are attached to the proximal part of the megaspore only by suprafilosal hairs. There are no maniculae. It is argued that
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Celia Olabarria
1999-12-01
Full Text Available En este trabajo se estudió la fauna malacológica asociada a la pesca de la langosta en aguas del Pacífico Tropical durante 1997-1998. Se recogieron un total de 1 081 individuos pertenecientes a 11 especies. Las mayores capturas se obtuvieron en otoño de 1997 (28.16% y en verano de 1998 (25.58%. Las especies dominantes fueron H. nigritus (83.10%, C. regius (8.04%, V. caestus (2.12%, C. brassica (1.85% y C. erythrostomus (1.75%, las cuales tienen importancia comercial. Se calculó la relación talla-peso, histogramas de frecuencia de tallas, y la relación de sexos para las especies dominantes. La relación de sexos fue de 1:1, salvo en C. erythrostomus y H. nigritus (2 machos: 1 hembra; en C. regius, C. erythrostomus y V. caestus el crecimiento fue alométrico mientras que en H. nigritus y C. brassica fue isométrico. Solamente, los machos de H. nigritus fueron más grandes que las hembras de la misma especie. Se encontraron diferencias significativas en la distribución de las especies respecto a la profundidad; C. erythrostomus apareció a mayores profundidades mientras que H. nigritus estuvo en zonas más someras. El tamaño de H. nigritus varió con la profundidad, temperatura y localidad.Mollusks associated to the spiny lobster fishery during 1997-1998 in the Tropical Pacific were surveyed. A total of 1 081 specimens of 11 species were collected. The greatest captures were in autumn 1997 (28.16% and summer 1998 (25.58%. Dominant species were Hexaplex nigritus (Philippi 1845 (83.10%, Chicoreus regius (Swainson 1821 (8.04%, Vasum caestus (Broderip 1833 (2.12%, C. brassica (Lamarck 1822 (1.85% and C. erythrostomus (Swainson 1831 (1.75%, which have commercial importance. Weight-height ratio, sex ratio and height frequency histograms were done for dominant species. Sex ratio was 1:1, except for C. erythrostomus and H. nigritus (2 males:1 female; C. regius, C. erythrostomus and V. caestus presented an allometric growth while H. nigritus and C
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A 3D photogrammetric reconstruction attempt of specimens of Badenian echinoids
Polonkai, Bálint; Raveloson, Andrea; Görög, Ágnes; Bodor, Emese; Székely, Balázs
2016-04-01
The rich echinoid fauna of the Badenian (Middle Miocene) from Budapest (Hungary) is well known for more than one hundred years. Along the road cuts and due to the construction of large buildings from 1960 to 2011, new Badenian outcrops with rich and well preserved echinoids were found in the city. Thus the main aim of this study was to revise historically collected echinoids (in the collection of Geological and Geophysical Institute of Hungary) from different parts of the city (Örs Vezér Square, Gyakorló Street, Rákos and District of Budafok-Tétény) and to classify the newly collected fossils, moreover to carry out the palaeoenvironmental reconstruction of the different localities. The specimens studied are from the Upper Badenian Leithakalk Formation Rákos Member, which consists of sandy limestone, calcareous loose sandstone with volcanic clast and/or calcarenite without terrigenous or volcanic clast. One of the most common echinoidea in the Badenian, the Parascutella gibbercula DE SERRES, 1829 is well known and researched in both morphological and taxonomic aspects. However there are some intraspecific morphological features that show sharp differences across the specimens: the adapical conical convexity is considerably different between several forms. The petalodium's length/width ratio is also different between many specimens. Other morphological characters for example peristomal and periproctal aperture and the food groove can also be different. These differences within this relatively small area could be determined by ecological conditions (such as substrate, palaeodepth), or can be related to taxonomical or pathological changes. For an appropriate comparison, quantification of these features is necessary. Photogrammetry is in general a useful and well-developed tool to reconstruct 3D surfaces of artefacts (e.g., in archaeology, cultural heritage, and also in palaeontology). In order to evaluate the differences found in P. gibbercula specimens various
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Echinoderms: their culture and bioactive compounds.
Kelly, M S
2005-01-01
Of the five extant classes of echinoderms, it is the sea urchins (Echinoidea) and the sea cucumbers (Holothuroidea) that are both commercially fished and heavily overexploited. In sea urchins, it is the gonad of both males and females, normally referred to as'roe', that is a sought-after food. In the sea cucumber, the principal product is the boiled and dried body-wall or 'bêche-de-mer' for which there is an increasing demand. Many sea urchin and sea cucumber fisheries still have no management system or restrictions in place, and for those that do, the prognosis for catches to continue even at a reduced level is poor. Cultivation of these species increasingly becomes a necessity, both for stock enhancement programs and as a means to meet market demand. Sea urchin culture has been practised on a large scale in Japan for many decades, and effective methods for the culture and reseeding of species in these waters have been long established. Juvenile urchins are produced in their millions in state-sponsored hatcheries, for release to managed areas of seafloor. Outside of Japan, sea urchin cultivation is still a fairly recent practice, less than 10 years old, and largely still at a research level, although a range of species are now being produced in a variety of different culture systems. It is essential that the culture systems are adapted to be species-specific and meet with local environmental constraints. Sea cucumber cultivation originated in Japan in the 1930s and is now well established there and in China. Methods for mass cultivation of the tropical Holothuria scabra are now well established and practised in India, Australia, Indonesia, the Maldives and the Solomon Islands, with the focus of the research effort for both temperate and tropical species being centred on the production of juveniles in hatcheries for the restoration and enhancement of wild stocks. Like many other marine organisms, echinoderms have been, and continue to be, examined as a source of
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Sea otters in the northern Pacific Ocean
Bodkin, James L.; Jameson, Ronald J.; Estes, James A.; LaRoe, Edward T.; Farris, Gaye S.; Puckett, Catherine E.; Doran, Peter D.; Mac, Michael J.
1995-01-01
About 250 years ago sea otters (Enhydra lutris) were distributed continuously from central Baja California, north and west along the Pacific Rim to Machatka Peninsula in Russia, and south along the Kuril Island to northern Japan (Kenyon 1969; Fig. 1a). Several hundred thousand sea otters may have occurred in the north Pacific region when commercial hunting began in the 18th century (Riedman and Estes 1990).At least two attributes of the sea otter have influenced humans, likely for as long as they have resided together along the coast of the north Pacific Ocean. First, sea otters rely on a dense fur, among the finest in the world, for insulation in the cold waters of the Pacific Ocean. The demand for sea otter fur led to their near extinction in the 19th century. The fur harvest, begun about 1740 and halted by international treaty in 1911, left surviving colonies, each likely numbering less than a few hundred animals, in California, south-central Alaska, and the Aleutian, Medney, and Kuril Islands (Fig. 1a). These individuals provided the nucleus for the recovery of the species. Today more than 100,000 sea otters occur throughout about 75% of their original range (fig. 1b). Immigration has resulted in near-complete occupation of the Aleutian and Kuril archipelagos and the Alaska peninsula. Successful translocations have resulted in viable populations in southeast Alaska, Washington, and British Columbia. Large amounts of unoccupied habitat remain along the coasts of Russia, Canada, the United States, and Mexico.The second potential source of conflict between sea otters and humans is that sea otters prey on and often limit some benthic invertebrate populations. Because some of these invertebrates are aso used by humans (Estes and VanBlaricom 1985), human perceptions about the effects of sea otter foraging on invertebrates sometimes differ. By limiting populations of herbivorous invertebrates (e.g., sea urchins [Echinoidea]) otters help maintain the integrity of kelp
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Morales Maria E
2005-02-01
Full Text Available Abstract Background Of the major families of long terminal repeat (LTR retrotransposons, the Pao/BEL family is probably the least well studied. It is becoming apparent that numerous LTR retrotransposons and other mobile genetic elements have colonized the genome of the human blood fluke, Schistosoma mansoni. Results A proviral form of Sinbad, a new LTR retrotransposon, was identified in the genome of S. mansoni. Phylogenetic analysis indicated that Sinbad belongs to one of five discreet subfamilies of Pao/BEL like elements. BLAST searches of whole genomes and EST databases indicated that members of this clade occurred in species of the Insecta, Nematoda, Echinodermata and Chordata, as well as Platyhelminthes, but were absent from all plants, fungi and lower eukaryotes examined. Among the deuterostomes examined, only aquatic species harbored these types of elements. All four species of nematode examined were positive for Sinbad sequences, although among insect and vertebrate genomes, some were positive and some negative. The full length, consensus Sinbad retrotransposon was 6,287 bp long and was flanked at its 5'- and 3'-ends by identical LTRs of 386 bp. Sinbad displayed a triple Cys-His RNA binding motif characteristic of Gag of Pao/BEL-like elements, followed by the enzymatic domains of protease, reverse transcriptase (RT, RNAseH, and integrase, in that order. A phylogenetic tree of deduced RT sequences from 26 elements revealed that Sinbad was most closely related to an unnamed element from the zebrafish Danio rerio and to Saci-1, also from S. mansoni. It was also closely related to Pao from Bombyx mori and to Ninja of Drosophila simulans. Sinbad was only distantly related to the other schistosome LTR retrotransposons Boudicca, Gulliver, Saci-2, Saci-3, and Fugitive, which are gypsy-like. Southern hybridization and bioinformatics analyses indicated that there were about 50 copies of Sinbad in the S. mansoni genome. The presence of ESTs
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Conodonts, Calcichordates and the Origin of Vertebrates
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J. Bergström
1998-01-01
Full Text Available Interpretation of early deuterostome evolution and relationships has been hampered by the lack of soft-part preservation in most groups. In addition, a recently revealed upside-down life orientation of vertebrates (the only real notoneuralians compared to other bilateral animals has been misinterpreted as evidence for a unique body design in all deuterostomes, misleading any search for relatives. Regarding echinoderms, the variety of body plans is confusing. The interpretation of some fossils with echinoderm-type calcite skeletons as “calcichordate” ancestors of chordates, however, involves a hypothetical reconstruction of an unusual body plan and a long series of hypothetical transitions. The number of necessary steps is much lower if cephalochordates (amphioxus or lancelet are derived directly from hemichordate enteropneusts. “Sensation interpretations” of fossils (Yunnanozoon, Cathaymyrus from Burgess Shale type deposits have added further confusion. Soft-part preservation of conodont animals, with V-shaped myomeres and a notochord, shows that they were segmented chordates, while probable eyes and teeth suggest that they were already on the vertebrate side. Die Interpretation früher Deuterostomia hinsichtlich ihrer Evolution und verwandtschaftlichen Beziehungen ist in den meisten Gruppen durch den Mangel an Weichkörpererhaltung sehr erschwert. Die kürzlich entdeckte Tatsache, daß Vertebraten, d. h. die einzigen echten Notoneuralia, im Gegensatz zu anderen bilateral symmetrischen Organismen eine mit ihrer ursprünglichen Oberseite nach unten gerichtete Lebensstellung einnehmen, hat zu der irrtümlichen Ansicht geführt, daß alle Deuostomia über einen im Tierreich einzigartigen Bauplan verfügen. Diese Interpretation brachte naturgemäß jede Suche nach Verwandtschaftsverhältnissen auf Abwege. Hinsichtlich der Echinodermata ist die bauplanmäßige Variation in der Tat verwirrend. Die Interpretation einiger Fossilien mit
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Marine biodiversity of Aotearoa New Zealand.
Gordon, Dennis P; Beaumont, Jennifer; MacDiarmid, Alison; Robertson, Donald A; Ahyong, Shane T
2010-08-02
The marine-biodiversity assessment of New Zealand (Aotearoa as known to Māori) is confined to the 200 nautical-mile boundary of the Exclusive Economic Zone, which, at 4.2 million km(2), is one of the largest in the world. It spans 30 degrees of latitude and includes a high diversity of seafloor relief, including a trench 10 km deep. Much of this region remains unexplored biologically, especially the 50% of the EEZ deeper than 2,000 m. Knowledge of the marine biota is based on more than 200 years of marine exploration in the region. The major oceanographic data repository is the National Institute of Water and Atmospheric Research (NIWA), which is involved in several Census of Marine Life field projects and is the location of the Southwestern Pacific Regional OBIS Node; NIWA is also data manager and custodian for fisheries research data owned by the Ministry of Fisheries. Related data sources cover alien species, environmental measures, and historical information. Museum collections in New Zealand hold more than 800,000 registered lots representing several million specimens. During the past decade, 220 taxonomic specialists (85 marine) from 18 countries have been engaged in a project to review New Zealand's entire biodiversity. The above-mentioned marine information sources, published literature, and reports were scrutinized to give the results summarized here for the first time (current to 2010), including data on endemism and invasive species. There are 17,135 living species in the EEZ. This diversity includes 4,315 known undescribed species in collections. Species diversity for the most intensively studied phylum-level taxa (Porifera, Cnidaria, Mollusca, Brachiopoda, Bryozoa, Kinorhyncha, Echinodermata, Chordata) is more or less equivalent to that in the ERMS (European Register of Marine Species) region, which is 5.5 times larger in area than the New Zealand EEZ. The implication is that, when all other New Zealand phyla are equally well studied, total marine
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Complexity, Compassion and Self-Organisation: Human Evolution and the Vulnerable Ape Hypothesis
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Nick P. Winder
2015-06-01
Full Text Available Humans are agents capable of helping others, learning new behaviours and forgetting old ones. The evolutionary approach to archaeological systems has therefore been hampered by the 'modern synthesis' - a gene-centred model of evolution as a process that eliminates those that cannot handle stress. The result has been a form of environmental determinism that explains human evolution in terms of heroic struggles and selective winnowing. Biologists committed to the modern synthesis have either dismissed agency as a delusion wrought in our bodies by natural selection, or imposed a sharp, Cartesian split between 'natural' and 'artificial' ecologies. We revisit the seminal literature of evolutionary biology and show that the paradigmatic fault lines of 21st century anthropology can be traced back to the 19th century and beyond. Lamarck had developed a two-factor evolutionary theory - one factor an endogenous tendency to become more advanced and complex, the other an exogenous constraint that drove organisms into conformity with environment. Darwin tried to eliminate the progressive tendency and imposed linearity constraints on evolution that Thomas Henry Huxley rejected. When experimental evidence falsified Darwin's linear hypothesis, the race began to develop a new, gene-centred model of evolution. This became the modern synthesis. The modern synthesis is now under pressure from the evidence of anthropology, sociology, palaeontology, ecology and genetics. An 'extended synthesis' is emerging. If evolution is adequately summarised by the aphorism survival of the fittest, then 'fitness' cannot always be defined in the heroic sense of 'better able to compete and reproduce'. The fittest organisms are often those that evade selective winnowing, even when their ability to compete and reproduce has been compromised by their genes. Characteristically human traits like language, abstraction, compassion and altruism may have arisen as coping strategies that
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Patrícia P. Silva
Full Text Available Este estudo teve como objetivos descrever o ciclo gametogênico e o comportamento reprodutivo da população de Iphigenia brasiliana (Lamarck,1818 no estuário do rio Subaé, Baía de Todos os Santos, Bahia. Os bivalves foram coletados de novembro de 2001 a novembro de 2002. Um total de 244 espécimes foi medido (eixo anteroposterior, eviscerado, fixado, desidratado e incluído em parafina. O estudo histológico das gônadas foi realizado através de cortes seriados do tecido gonadal, de 5 mm de espessura, e corados pela HE. O tamanho médio mínimo da primeira maturação sexual (Lpm foi estimado a partir da distribuição das frequências relativas de jovens e adultos, por classe de comprimento dos indivíduos. As frequências relativas dos sexos em cada estádio de desenvolvimento foram consideradas conjuntamente para a análise do comportamento reprodutivo da população, e, em separado, para avaliar a sincronia do ciclo sexual entre machos e fêmeas. Foi observada uma variação de tamanhos entre 9,1 e 66,6 mm, com comprimento médio de 50,2 mm. O estudo não demonstrou diferença significativa entre os tamanhos de machos e fêmeas. Não foi possível observar a diferenciação de sexos em 2,1% dos indivíduos analisados. 51,6% dos indivíduos foram identificados como machos (M e 46,3% como fêmeas (F, não sendo constatadas diferenças significativas entre o número médio de machos e fêmeas, resultando numa proporção de M:F de 1,1:1. O Lpm foi estimado em 11,4 mm, mas apenas ao alcançarem comprimento médio de 34,4 mm, todos os indivíduos foram considerados adultos. Foram caracterizados quatro estádios de evolução do desenvolvimento gonadal em fêmeas e machos. A análise dos diferentes estádios permitiu a observação dos fenômenos de atresia e inversão sexual em fêmeas. O ciclo reprodutivo apresentou eliminação contínua de gametas, com maiores intensidades reprodutivas nos meses de novembro de 2001 a abril de 2002 e, tamb
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G. A. Salcedo
2013-01-01
Full Text Available Los cultivos de arroz en la cuenca baja del río Daule, Ecuador, son afectados por el caracol manzana. La pérdida estimada es de 40 al 60% de la producción/ha. El agricultor, para evitar pérdidas considerables, aplica agroquímicos en dosis elevadas, desequilibrando la fauna y microfauna nativa, agravando el problema. Razón por la cual, se evaluó la patogenicidad de H. bacteriophora sobre el caracol manzana, con tres dosis; mediante un diseño completamente al azar (DCA con cuatro tratamientos y cinco repeticiones. Los resultados muestran el 100% de mortalidad por septicemia a las 96 horas de la inoculación, con relación al testigo.
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G. A. Salcedo
2013-01-01
Los cultivos de arroz en la cuenca baja del río Daule, Ecuador, son afectados por el caracol manzana. La pérdida estimada es de 40 al 60% de la producción/ha. El agricultor, para evitar pérdidas considerables, aplica agroquímicos en dosis elevadas, desequilibrando la fauna y microfauna nativa, agravando el problema. Razón por la cual, se evaluó la patogenicidad de H. bacteriophora sobre el caracol manzana, con tres dosis; mediante un diseño completamente al azar (DCA) con cuatro tratamientos ...
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Spivak, M
1987-01-01
Some ideas, whether right or wrong, seem never to die, whatever might be the general evolution of knowledge, of science, or simply of good common sense. This is exactly the case with physical education or sports. For centuries, and especially since the middle of the nineteenth century, its advocates have fought for recognition of its all-round virtues, taken as a concept. But to attain a high level of recognition, not only in society but in official government circles, certain conditions were necessary. Education as a whole, around the middle of the nineteenth century, had to be strict and similar to military drill to be considered efficient, although the French middle classes and bourgeoisie had very little taste for the military. Although they admired physical prowess they had a horror of regimentation. But later on, when the Prussians so easily defeated Austria, feelings of doubt in French superiority began to spread, and a handful of theoreticians of physical exercise tried to show that to combat the so-called degeneration of the race, it was essential to impose a system of education in which physical exercise, coupled with military drill, still had an important place. As scientific arguments they referred to the theories of evolution and its then accepted principle, according to Lamarck, or the transmission of acquired properties and character. Darwin was still unknown in France at that time. These zealous advocates succeeded in convincing the Minister of Public Education, Victor Duruy, to include gymnastics in the normal course of studies in all schools, and by 1869 one can say that a craze for all types of physical exercise and sport had spread into many levels of society. That was the start of a never-ending movement which has passed through various stages of evolution corresponding to the changes in society itself. It has therefore changed its methods, its ways, its forms, but the overall principle remains the same, in spite of the improved understanding
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International Nuclear Information System (INIS)
Akhtar, Mubeena; Moosa Hasany, S.; Bhanger, M.I.; Iqbal, Shahid
2007-01-01
Moringa oleifera pods Lamarck (Drumstick or Horseradish) is a multipurpose medium or small size tree from sub-Himalayan regions of north-west India and indigenous to many parts of Asia, Africa, South America, and in the Pacific and Caribbean Islands. Its pods (MOP) have been employed as an inexpensive and effective sorbent for the removal of organics, i.e., benzene, toluene, ethylbenzene and cumene (BTEC) from aqueous solutions using HPLC method. Effect of different parameters, i.e., sorbent dose 0.05-0.8 g, 25 cm -3 agitation time 5-120 min, pH 1-10, temperature 283-308 K and concentration of sorbate (1.3-13) x 10 -3 , (1.1-11) x 10 -3 , (0.9-9) x 10 -3 , (0.8-8) x 10 -3 mol dm -3 , on the sorption potential of MOP for BTEC have been investigated. The pore area and average pore diameter of the MOP by BET method using nitrogen as a standard are calculated to be 28.06 ± 0.8 m 2 g -1 and 86.2 ± 1.3 nm respectively. Freundlich, Langumir and Dubinin-Radushkevich (D-R) sorption isotherms were employed to evaluate the sorption capacity of MOP. Sorption capacities of BTEC onto MOP have been found to be 46 ± 10, 84 ± 9, 101 ± 4, 106 ± 32 mmol g -1 by Freundlich, 8 ± 0.1, 9 ± 0.1, 10 ± 0.3, 9 ± 0.1 mmol g -1 by Langumir and 15 ± 1, 21 ± 1, 23 ± 2, 22 ± 3 mmol g -1 by D-R isotherms respectively, from BTEC solutions at 303 K. While the mean energy of sorption process 9.6 ± 0.3, 9.2 ± 0.2, 9.3 ± 0.3, 9.5 ± 0.4 kJ mol -1 for BTEC is calculated by D-R isotherm only. Rate constant of BTEC onto MOP 0.033 ± 0.003, 0.030 ± 0.002, 0.029 ± 0.002, 0.027 ± 0.002 min -1 at solution concentration of 1.3 x 10 -3 , 1.1 x 10 -3 , 0.9 x 10 -3 and 0.8 x 10 -3 mol dm -3 and at 303 K have been calculated by employing Lagergren equation. Thermodynamic parameters ΔH -8 ± 0.4, -10 ± 0.6, -11 ± 0.7, -11 ± 0.7 kJ mol -1 , ΔS -22 ± 2, -26 ± 2, -27 ± 2, -29 ± 3 J mol -1 K -1 and ΔG 303K -0.9 ± 0.2, -1.9 ± 0.2, -2.3 ± 0.1 and -2.6 ± 0.2 kJ mol -1 were also estimated
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Energy Technology Data Exchange (ETDEWEB)
Akhtar, Mubeena [National Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro-76080 (Pakistan)]. E-mail: profmarao@yahoo.com; Moosa Hasany, S. [Pakistan Institute of Engineering and Applied Sciences, PO Nilore, Islamabad (Pakistan); Bhanger, M.I. [National Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro-76080 (Pakistan); Iqbal, Shahid [Department of Chemistry, University of Sargodha, Sargodha-40100 (Pakistan)]. E-mail: ranashahid313@gmail.com
2007-03-22
Moringa oleifera pods Lamarck (Drumstick or Horseradish) is a multipurpose medium or small size tree from sub-Himalayan regions of north-west India and indigenous to many parts of Asia, Africa, South America, and in the Pacific and Caribbean Islands. Its pods (MOP) have been employed as an inexpensive and effective sorbent for the removal of organics, i.e., benzene, toluene, ethylbenzene and cumene (BTEC) from aqueous solutions using HPLC method. Effect of different parameters, i.e., sorbent dose 0.05-0.8 g, 25 cm{sup -3} agitation time 5-120 min, pH 1-10, temperature 283-308 K and concentration of sorbate (1.3-13) x 10{sup -3}, (1.1-11) x 10{sup -3}, (0.9-9) x 10{sup -3}, (0.8-8) x 10{sup -3} mol dm{sup -3}, on the sorption potential of MOP for BTEC have been investigated. The pore area and average pore diameter of the MOP by BET method using nitrogen as a standard are calculated to be 28.06 {+-} 0.8 m{sup 2} g{sup -1} and 86.2 {+-} 1.3 nm respectively. Freundlich, Langumir and Dubinin-Radushkevich (D-R) sorption isotherms were employed to evaluate the sorption capacity of MOP. Sorption capacities of BTEC onto MOP have been found to be 46 {+-} 10, 84 {+-} 9, 101 {+-} 4, 106 {+-} 32 mmol g{sup -1} by Freundlich, 8 {+-} 0.1, 9 {+-} 0.1, 10 {+-} 0.3, 9 {+-} 0.1 mmol g{sup -1} by Langumir and 15 {+-} 1, 21 {+-} 1, 23 {+-} 2, 22 {+-} 3 mmol g{sup -1} by D-R isotherms respectively, from BTEC solutions at 303 K. While the mean energy of sorption process 9.6 {+-} 0.3, 9.2 {+-} 0.2, 9.3 {+-} 0.3, 9.5 {+-} 0.4 kJ mol{sup -1} for BTEC is calculated by D-R isotherm only. Rate constant of BTEC onto MOP 0.033 {+-} 0.003, 0.030 {+-} 0.002, 0.029 {+-} 0.002, 0.027 {+-} 0.002 min{sup -1} at solution concentration of 1.3 x 10{sup -3}, 1.1 x 10{sup -3}, 0.9 x 10{sup -3} and 0.8 x 10{sup -3} mol dm{sup -3} and at 303 K have been calculated by employing Lagergren equation. Thermodynamic parameters {delta}H -8 {+-} 0.4, -10 {+-} 0.6, -11 {+-} 0.7, -11 {+-} 0.7 kJ mol{sup -1}, {delta
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Lenin Arias-Rodriguez
2007-12-01
Full Text Available El cariotipo de Plicopurpura pansa y P. columellaris fue determinado a partir de 17 y 13 especímenes adultos respectivamente. Adicionalmente, se utilizaron ocho cápsulas de P. pansa. Contamos 186 campos mitóticos en P. pansa: 59 en los adultos y 127 en los embriones; y 118 campos en P. columellaris. En ambas especies se observaron números cromosómicos desde 30 hasta 42. Las variaciones en número cromosómico fueron identificadas en cada individuo, no habiendo ninguna relación con los tejidos (branquias, músculo y estómago empleados. El número modal diploide típico fue de 2n=36 cromosomas en ambas especies. En los especímenes adultos seleccionamos cinco de las mejores dispersiones cromosómicas para armar el cariotipo. Calculamos los estadísticos citogenéticos clásicos, longitudes relativas, proporción de brazos, índice centromérico y la diferencia entre brazos. Identificamos en ambas especies tres pares de cromosomas metacéntricos y quince pares de cromosomas telocéntricos. Esta clasificación no fue suficientemente robusta, por lo que dividimos el complemento cromosómico de cada especie en cuatro grupos ("a", "b", "c" y "d" utilizando como criterio las longitudes relativas (p+q. Hubo diferencias significativas entre grupos cromosómicos por especie y entre especies, los tres primeros pares de cromosomas (grupo "a" birrámeos y los dos últimos pares (grupo "d" monorrámeos menores (análisis de varianza de dos vías, pKaryotypes of the purple snails Plicopurpura pansa and Plicopurpura columellaris (Gastropoda: Muricidae. The karyotypes of the purple snails Plicopurpura pansa (Gould, 1853 and P. columellaris (Lamarck, 1816 were established from 17 and 13 adults, respectively; and from eight capsules with embryos of P. pansa. In P. pansa were counted 59 mitotic fields in the adults and 127 in embryos; and 118 fields in P. columellaris. Chromosome numbers from 30 to 42 were observed in both species. Such a variation was
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Barahona, Ana
1997-12-01
Full Text Available Not available.La idea de progreso en Biología está ligada al concepto de scala naturae o la gran cadena del ser que se puede trazar hasta Aristóteles. Esta noción de que los organismos vivientes pueden clasificarse en una jerarquía de inferior a superior tomó formas nuevas en los siglos XVII y XVIII. En el siglo XVIII, naturalistas como Buffon, Bonnet y Robinet se habían preguntado si podíamos hablar de un patrón definido de desarrollo. En el siglo XIX, Lamarck postula la idea de que existe una progresión de los organismos menos avanzados a los organismos más avanzados. Posteriormente, la teoría de la evolución añade la dimensión temporal y de continuidad genética o histórica a la clasificación jerárquica de los seres vivos. Darwin pensaba que la selección natural traía como resultado el perfeccionamiento y que éste inevitablemente conduciría al progreso gradual de la organización. Herbert Spencer se convirtió en uno de los darwinistas más radicales del siglo XIX y principios del XX. Para Spencer la idea de progreso se aplicaba no solo al mundo biológico sino que era parte de una ley general, que dirigía lo simple hacia lo complejo, lo homogéneo a lo heterogéneo. Posteriormente, Julian Huxley, Theodosius Dobzhansky, Ernst Mayr, George Gaylord Simpson y Ledyard Stebbins —conocidos como los arquitectos de la Sintesis Moderna— comparten una visión progresionista de la evolución biológica. La noción de progreso evolutivo, en la actualidad, es sumamente controvertida, y se pueden distinguir básicamente tres diferentes perspectivas. La primera, defendida por Michael Ruse y David Hull entre otros, sostiene que no existe evidencia científica que nos lleve a aceptar cierta «direccionalidad» en la evolución biológica. Una segunda visión, defendida por Stephen J. Gould, sostiene que, en la medida en que reemplacemos el término de progreso (ya que éste es antropocéntrico por el de «noción operacional de
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Thomas Fouilleron
2011-09-01
le géologue Faujas de Saint-Fond un filon charbonneux qui, un temps, fait croire à une possible industrialisation de la Principauté. Homme de son temps et des usages de son ordre, le dernier prince d’Ancien Régime sacrifie à la frénésie mesmérienne et à la mode parisienne des expériences publiques. Même si l’histoire continue à être un goût dominant, les « sciences et arts » sont bien représentés dans les bibliothèques des Grimaldi au siècle des Lumières. Quelques ouvrages savants et techniques leur sont dédiés. Les jeunes princes reçoivent les rudiments d’une éducation scientifique, en particulier dans le domaine des mathématiques. Georges Cuvier est même, pendant la Révolution, le précepteur fortuit du futur prince Honoré V (1778-1841. L’exemple des souverains entraîne quelques sujets, gens de cour ou ecclésiastiques de la Principauté, à s’investir dans les sciences. Le milieu naturel local les amène souvent à s’intéresser à la botanique. Lamarck, en garnison à Monaco, y aurait d’ailleurs fait ses premières observations.Si, dans le domaine du connoissorship scientifique, les Grimaldi suivent les usages de leur temps, peut-être plus qu’ils ne les précèdent, ils instrumentalisent les sciences et les savants à des fins de reconnaissance culturelle et de légitimation politique. Laboratoire des grandes cours européennes, le palais de Monaco peut ainsi être vu comme un observatoire privilégié des rapports qu’entretiennent, aux xviie et xviiie siècles, les princes et les savants, et un marqueur de la propagation de la culture scientifique jusque dans les petites cours.
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1998-01-01
revisão sistemática dos equinóides regulares (ECHINODERMATA-ECHINOIDEA procedentes das rochas da Formação Pirabas (Oligo-Mioceno, Pará, Brasil. São redescritos Phyllacanthus priscus Brito & Ramirez, Histocidaris sp. e Prionocidaris sp., e são assinaladas, pela primeira vez, radíolos em “forma de leque” no Cenozóico das Américas atribuídos ao gênero “Cidaris”, e a primeira carapaça de um euequinóide regular, Psammechinus sp., em rochas do Cenozóico do Brasil. As análises tafonômica e paleoecológica preliminares sugerem uma deposição dos sedimentos da Formação Pirabas em mar de águas quentes e tranqüilas, sujeito a ações de tempestades, com condições excepcionais de fossilização localizadas. A nível filogenético é reafirmada a estreita relação dos equinóides regulares assinalados nas rochas da Formação Pirabas, com formas similares existentes na Província Faunística Caribeana durante o Cenozóico. Nome: Margareth de Toledo Conte Zulian Título: Um Estudo sobre Infiltração de Águas Pluviais em Fraturas Naturais na Porção Oeste da Serra da Carioca, Município do Rio de Janeiro Orientador: Eurípedes do Amaral Vargas Jr. Resumo: Através do mapeamento de duas áreas-piloto representativas da Serra da Carioca, o Morro da Formiga (vertente noroeste e a Ponta do Marisco (vertente sudoeste, verificou-se que a serra é seccionada por um sistema de fraturas, o qual apresenta duas famílias principais de direções NW-SE e NE-SW, com mergulhos subverticais. Famílias secundárias de direções aproximadas E-W e N-S, com mergulhos subverticais, NW-SE, com baixos ângulos de mergulho para SW e ainda E-W, com baixos ângulos de mergulho para S também são observadas e caracterizadas como juntas de alívio. Em todas as famílias foram estudadas as propriedades geométricas (orientação, persistência, espaçamento, a percolação de fluxo, as aberturas e o tipo de preenchimento, com o objetivo de entender o papel das fraturas na