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| CHAVES,ÓSCAR M. |
| The scientific revolution probably began at 16th century with the heliocentric theory of the eminent astronomer Nicolaus Copernicus, but it was culminated with the masterful discoveries of Galileo Galilei and Isaac Newton at 17th century who revealed that planet movements around the sun and other similar phenomena can be explained by simple mechanical laws of physics and astronomy. However, the origin, complexity and configuration of living beings remained in the mystery until 19th century, with the publication of "On the origin of species". In this essay I discuss the importance of the Darwinian scientific revolution, its beginnings, and the main objections of creationists to his evolutionary ideas. Darwin demonstrated that the origin and complexity of... |
| Tipo: Journal article |
Palavras-chave: Creationism; Darwin; Evolution; Religion; Scientific revolution. |
| Ano: 2010 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2010000200004 |
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| SABAT,PABLO; NESPOLO,ROBERTO F; BOZINOVIC,FRANCISCO. |
| Birds living in desert environments have been the preferred models for the study of physiological adaptations to water scarcity. Passerine birds living in marine coastal habitats face similar problems, yet physiological adaptations to water conservation in such species have been poorly documented. We measured total evaporative water loss (TEWL) and rates of oxygen consumption (VO2) in three species of passerine birds dwelling in marine and fresh water habitats. Mass specific total evaporative water loss was significantly lower in the marine species, Cinclodes nigrofumosus, than in species inhabiting areas near freshwater sources. We found a positive relationship between TEWL and VO2. The ratio of TEWL to VO2 (relative evaporative water loss, RTEWL) showed... |
| Tipo: Journal article |
Palavras-chave: Evaporative water loss; Cinclodes; Osmoregulation; Passerines; Salt. |
| Ano: 2004 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2004000200001 |
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| DÍAZ-JARAMILLO,MAURICIO; MUÑOZ,PAMELA; DELGADO-BLAS,VÍCTOR; BERTRÁN,CARLOS. |
| This study is based on the identification and distribution of spionid polychaetes in relation to abiotic characteristics of the environment at the mouth of the Valdivia-Tornagaleones estuary in south-central Chile. Four samplings were carried out in 2005, in which eight species were identified including Aquilaspio peruana, Boccardia polybranchia, Carazziella carrascoi, Dipolydora socialis, Minuspio patagónica, Rhynchospio glutaea, Scolelepis quinquedentata and Spiophanes sp. As it is typical of other estuaries in south central Chile, spionids were an important component of the macroinfauna of the Valdivia estuary. The distribution of the Spionidae family in the system showed higher species richness in the outer reach of the estuary but higher abundance... |
| Tipo: Journal article |
Palavras-chave: Polychaeta; Spionidae; Distribution; Estuary; Salinity; Sediments; Chile. |
| Ano: 2008 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2008000400005 |
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| CAMUS,PATRICIO A; NAVARRETE,ARTURO H; SANHUEZA,ÁLVARO G; OPAZO,L. FELIPE. |
| Polyplacophorans are common herbivores on rocky shores, but basic aspects of their ecology remain scarcely studied and their role within communities could be more complex than previously considered. Such is the case of Acanthopleura echinata (Barnes), one of the largest and most conspicuous chitons in the world, and at the same time, one of the least known intertidal species in the southeastern Pacific. To improve the basic ecological knowledge of this potentially important intertidal consumer, we studied the diet of A. echinata and its variation among sites of varying levels of coastal upwelling spread over 1000 km along the coast of northern Chile. A seasonal evaluation of diet, body size distribution and density at sites expected to vary in overall... |
| Tipo: Journal article |
Palavras-chave: Body size; Intertidal; Niche breadth; Omnivory; Upwelling. |
| Ano: 2012 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2012000100010 |
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| MARQUET,PABLO A. |
| In this essay I point out to two processes that can potentially complement the classical view of evolution by natural selection as outlined by Darwin, which captures only part of the processes driving adaptive evolution. This classical view should be complemented with sources of order generated within the biological system itself in response to its own structure and dynamics (i.e. self-organization) and by considering the existence of a fundamental circularity in the interaction between the organism and its environment, such that the action of the organisms modify their selective environment thereby affecting their own evolution. The formalization and inclusión of these two processes (and their interaction) represent major challenges and opportunities for... |
| Tipo: Journal article |
Palavras-chave: Darwin; Natural selection; Self-organization. |
| Ano: 2009 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2009000400004 |
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| PEÑALOZA,ALEJANDRO; CAVIERES,LOHENGRIN A.; ARROYO,MARY T.K.; TORRES,CRISTIAN. |
| El bosque esclerófilo montano de Chile central (32-33° S, 1.500-2.100 m de altitud) está dominado por poblaciones de Kageneckia angustifolia (Rosaceae), especie semidecidua de verano que forma un dosel muy abierto. Esto sugiere que, a diferencia de lo que ocurre en el matorral esclerófilo de menor altitud donde el cerrado dosel de árboles y arbustos generan condiciones microclimáticas diferentes a los espacios abiertos, en el bosque montano no existiría una marcada diferencia microclimática entre bajo el dosel y los espacios abiertos. Por otro lado, en el bosque montano, las precipitaciones ocurren principalmente en forma de nieve, la que se acumula preferentemente en los espacios entre los árboles, pudiendo facilitar el reclutamiento de nuevos individuos... |
| Tipo: Journal article |
Palavras-chave: Efecto nodriza; Microclima; Reclutamiento; Bosque montano; Chile central. |
| Ano: 2001 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2001000300005 |
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| HERNANDEZ,CRISTIAN; GALLEGUILLOS,RICARDO; OYARZUN,CIRO. |
| Se han planteado variadas hipótesis sobre relaciones taxonómicas entre las especies de Merluccius, proponiéndose la existencia de dos subespecies Merluccuis gayi gayi y Merluccius gayi peruanus en el Pacífico Sureste; aunque hasta el momento no existen evidencias suficientes que respalden tal hipótesis. En el presente trabajo se analizan las diferencias genéticas entre ambas subespecies mediante electroforesis de proteínas. Se procesaron 25 individuos de M. gayi gayi de la zona de Talcahuano (Chile) y 25 individuos de M. gayi peruanus del Puerto de Paita (Perú). Se detectó el producto génico de 33 loci homólogos. Los taxa presentan movilidad diferencial de los alelos en los loci monomórficos EM-2*, AP-1* y CA-1* y en el locus polimórfico EST-3*. Merluccius... |
| Tipo: Journal article |
Palavras-chave: Merluza; Distancia genética; Paleobiogeografía; Chile. |
| Ano: 2000 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2000000100003 |
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| FIGUEROA,FÉLIX L.; VIÑEGLA,BENJAMÍN. |
| The effects of solar ultraviolet (UV) radiation during daily cycles on photosynthesis and two key enzymes involved in carbon incorporation, the carbonic anhydrase, and in inorganic nitrogen reduction, the nitrate reductase, of macroalgae from southern Spain are presented. During daily cycles, photoinhibition in several intertidal macroalgae, expressed as decrease in the effective quantum yield from the morning to noon time, was linearly dependent on the daily integrated irradiance. However, recovery, expressed as the increase in the effective quantum yield from noon to the afternoon, presented a different pattern; full recovery was found below daily integrated irradiance of 1.0 x10(4) kJ m-2. However, recovery reached only 50 % at higher irradiances. The... |
| Tipo: Journal article |
Palavras-chave: Carbonic anhydrase; Chlorophyll fluorescence; Effective quantum yield; Nitrate reductase; Ultraviolet radiation. |
| Ano: 2001 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2001000200003 |
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| GORDON,CALEB E.. |
| This paper is a critical literature review on the topic of the coexistence of similar species within ecological communities. A conceptual framework is provided for dividing coexistence studies and concepts into three distinct time scales. The first six sections deal primarily with ecological-scale, or mesoscale coexistence, defined as coexistence in the classic sense of the competitive exclusion principle and Lotka-Volterra models, wherein interacting populations have had enough time to reach equilibrium. The first four sections briefly review resource partitioning studies and competitive coexistence models, and discuss the relative contributions of, and interaction between empirical and theoretical approaches to the problem of ecological-scale... |
| Tipo: Journal article |
Palavras-chave: Coexistence; Competition; Community structure; Resource partitioning; Niche. |
| Ano: 2000 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2000000100016 |
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| BAO-MING,GE; ZHEN-XING,LI; DAI-ZHEN,ZHANG; HUA-BIN,ZHANG; ZONG-TANG,LIU; CHUN-LIN,ZHOU; BO-PING,TANG. |
| We evaluated the diversity of soil macrofauna communities inhabiting urban green spaces in Yancheng City, an urbanizing city located east of China. In the end of April 2011, the taxonomic richness, abundance and composition of soil macrofauna communities were assessed and compared among five types of green space (poplar forest, rapeseed farm, grassland in park, lawn and nursery garden) and three depth layers in the soil, with taxonomic resolution attained at the order level. Taxonomic richness (orders) and abundance were significantly different among green spaces. Diversity indices (Margalef's taxonomic richness R and Shannon-Weaver diversity index H') were higher in poplar forest, grassland in park and nursery garden than in rapeseed farm and lawn.... |
| Tipo: Journal article |
Palavras-chave: China; Diversity; Soil layer; Urbanization; Yancheng City. |
| Ano: 2012 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2012000200008 |
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| CISTERNAS,MARCO; TORRES,LAURA; URRUTIA,ROBERTO; ARANEDA,ALBERTO; PARRA,OSCAR. |
| Se comparan, a través de registros sedimentarios, palinológicos y diatomológicos, dos momentos de la historia ambiental del sistema lacustre de San Pedro. El primero, corresponde al periodo prehispánico, representando a las condiciones prístinas o línea base del sistema. El segundo periodo, el más reciente, representa aproximadamente a los últimos diez años de intervención antrópica. Para lograr lo anterior, se recolectaron muestras verticales de sedimento del fondo en los dos lagos del sistema lacustre de San Pedro (Lagunas Grande y Chica). Se realizaron análisis cronológicos (C14), palinológicos y diatomológicos de los estratos superiores e inferiores de la columna sedimentaria. Los resultados indican que el sistema lacustre de San Pedro ha experimentado... |
| Tipo: Journal article |
Palavras-chave: Comparación ambiental; Registros sedimentarios; Diatomeas; Polen; Lagos. |
| Ano: 2000 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2000000100014 |
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| Merlo,Carolina; Abril,Adriana. |
| BACKGROUND: We analyzed the following characteristics of water self-depuration capacity along a polluted river (Suquía River) in Argentina: (a) abundance of microbial metabolic groups, (b) cover and type of vegetation, and (c) type and concentration of soil and sediment humic substances. The objective was to establish the modifications of water self-depuration characteristics of the polluted sites in comparison to a reference site in order to provide basic data for ecological restoration programs. Five samples of riparian soil, water, and sediments were collected at a reference site and five polluted sites during low- and high-flow water periods. In each site the vegetation type and soil cover were recorded. In all samples the abundance of ammonifiers,... |
| Tipo: Journal article |
Palavras-chave: Humic substances; Microbial groups; Sediments; Sulfate reducer; Vegetation type. |
| Ano: 2014 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2014000100011 |
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| FERNÁNDEZ,MIRIAM; BRANTE,ANTONIO. |
| The quantification of the costs associated with parental care of marine invertebrates requires a first and necessary step, which is the identification of the different forms of care exhibited by this group. Among marine invertebrates, provision of oxygen to the aggregation of embryos may be critical, although most evidence on the link between oxygen limitation and parental care is indirect. Species which show active behavior directed at providing oxygen to the brood offer a good model to establish the direct link between behavioural patterns and oxygen provision to the embryos, and to estimate the costs associated with this form of care. In this manuscript, we conducted a review of the current knowledge about oxygen limitation in embryos aggregations of... |
| Tipo: Journal article |
Palavras-chave: Reproduction; Brood care; Crabs; Oxygen; Marine invertebrates. |
| Ano: 2003 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2003000200003 |
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| SAAVEDRA,CARMEN C. R.; NAPP,MARLY; REGULY,MARIA LUIZA; VALENTE,VERA LUCIA S. |
| Natural populations of Drosophila willistoni collected both in urban sites and in the wild, as control, were analysed with respect to their isoenzyme polymorphisms in six loci of enzyme systems, through horizontal electrophoresis. The first pool of populations was collected and analysed during the years 1987 and 1988, and the other during 1992 and 1993, in comparable seasons. The level of enzymatic polymorphism first detected was smaller in comparison to that observed four years later, suggesting an increase of variability along the time elapsed since the first sampling of this species, in the city of Porto Alegre. Our findings are suggestive of an increasing adjustment of the species to this new environment |
| Tipo: Journal article |
Palavras-chave: Drosophila willistoni; Urban populations; Isoenzymes. |
| Ano: 2001 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2001000000010 |
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| VERGARA,OLIVIA E; JEREZ,VIVIANE; PARRA,LUIS E. |
| Los coleópteros, por estar asociados con formaciones vegetales, presentar gran abundancia y diversidad ecológica, rangos de distribución restringidos y alto endemismo, constituyen buenos indicadores de la biodiversidad de un territorio. En la Región del Biobío, área crítica de conservación, estudios sobre la riqueza taxonómica y distribución de coleópteros son muy pocos a pesar de su carácter transicional y de constituir una zona de "puntos calientes" de diversidad a nivel mundial. Nuestros objetivos fueron conocer la composición taxonómica y representatividad regional de coleópteros, determinar sectores con mayor riqueza de especies y relacionar los patrones de distribución de las especies con formaciones vegetales y áreas silvestres protegidas de la... |
| Tipo: Journal article |
Palavras-chave: Insecta; Coleoptera; Formaciones vegetacionales; Áreas Silvestres Protegidas del Estado; Análisis de parsimonia de endemismos (PAE). |
| Ano: 2006 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2006000300008 |
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| Orellana,José I; Smith-Ramírez,Cecilia; Rau,Jaime R; Sade,Soraya; Gantz,Alberto; Valdivia,Carlos E. |
| BACKGROUND: Frugivorous birds are phenologically linked to the fruits that they eat. When there is less fruit in seasonal environments, frugivorous birds complement their diet by eating invertebrates. The depth of the phenological link between frugivorous birds and their dietary resources has not been studied until now. The objective was to determine the possible phenological synchrony between the Austral thrush (Turdus falcklandii) and its dietary resource, fruits and annelids, found in the fragmented forests in the South of Chile. RESULTS: The numbers of thrushes, annelids, and fruits in fragments of native forest and anthropogenic grassland in Chile's Lake District were estimated annually. Spatial variation (i.e., forest and grassland) and seasonal... |
| Tipo: Journal article |
Palavras-chave: Annelids; Fleshy fruit; Phenology; Seasonality; Turdus. |
| Ano: 2014 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2014000100010 |
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