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| Registros recuperados: 845 | |
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| CAMUS,PATRICIO A. |
| El año 2013 marcará el cierre de una etapa importante para la Revista Chilena de Historia Natural (RCHN), ya que a partir de 2014 comenzará a publicarse a través de la plataforma SpringerOpen, incluyendo algunos cambios relevantes en su diseño, manejo editorial, e idioma, entre otros. Por lo tanto en este artículo sintetizo algunos aspectos clave en la evolución de RCHN desde su fundación a fines del siglo 19, a través de dos períodos históricos: (a) 1897-1963, donde destaca la figura de su creador Carlos E. Porter y el rol de la Sociedad Chilena de Historia Natural, y (b) 1983-2013, su etapa reciente ligada a la Sociedad de Biología de Chile. Adicionalmente presento un breve análisis de la situación y el impacto de RCHN en su etapa moderna, incluyendo... |
| Tipo: Journal article |
Palavras-chave: Chile; Historia natural; Impacto. |
| Ano: 2013 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2013000400001 |
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| VALENZUELA,CARLOS Y; PÉREZ-ALZOLA,PATRICIA; SANTOS,MANUEL J. |
| The maximal value of 50 % of genetic recombination (RF = recombination fraction) between two linked gene loci has been explained by two models: (i) the restriction of crossovers to only two of the four chromatids of a tetrad (tetrad model); (ii) the limit of the occurrence of an odd number of crossovers between two loci, when the expected number of crossovers tends to infinite (odd-even model). This article shows that (i) is wrong. If tetrads were responsible for the maximal 50 % RF, sister chromatid exchanges (SCE) should display a maximal 100 % RF. In mammalian CHO cells we found that SCE yield a maximal 50 % recombination. Also, we demonstrated that the maximal 50 % RF for tetrads occurs because the sum of odd order coefficients in the binomial... |
| Tipo: Journal article |
Palavras-chave: 50 % recombination; Tetrads; Odd-even crossovers; SCE. |
| Ano: 2001 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2001000000015 |
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| ABOITIZ,FRANCISCO. |
| Although homology is central to evolutionary interpretations, establishing it has become a highly disputed issue in some instances. Here I argüe for a developmental understanding of evolution, where modifications of the developmental programs are a key source of evolutionary novelty. Although this perspective is not new, in comparative neurobiology it has remained controversial. Specifically, the evolutionary origin of the mammalian neocortex has been a particularly debated point. I propose a perspective that could help reconcile a long standing controversy: either the mammalian neocortex corresponds as a whole to the dorsal hemisphere of reptiles and birds, or alternatively its lateral aspect corresponds to the lateral cerebral hemisphere and is partly... |
| Tipo: Journal article |
Palavras-chave: Dorsal ventricular ridge; Neocortex; Pallium; Subventricular zone; Ventricular zone. |
| Ano: 2010 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2010000400002 |
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| GONZÁLEZ,ALEJANDRA; SANTELICES,BERNABÉ. |
| In late 2001 and early 2002, a dichotomous species of Codium appeared colonizing the low intertidal and shallow subtidal bottoms of Caldera Bay, northern Chile (27° 03 S, 70° 51 W). Due to the ecological and economic impact the species is having in Caldera Bay and its potential spread along the Chilean coastline, we studied the taxonomic identity of the species and examined its relationships with other dichotomous species of Codium reported for temperate Pacific South America. Morphological analyses suggest that the seaweeds from Caldera Bay belong to Codium fragile (Suringar) Hariot. Not only is there strong agreement in internal and external morphological characters, but among all the species reported for Peru and Chile, this is the only one exhibiting... |
| Tipo: Journal article |
Palavras-chave: Introduced species; Seaweed; Northern Chile. |
| Ano: 2004 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2004000200008 |
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| FOLGUERA,GUILLERMO; BOZINOVIC,FRANCISCO. |
| A los 150 años de la publicación de "El origen de las especies" de Charles Darwin, numerosos homenajes se han realizado en diferentes ciudades del mundo. Sin embargo, es importante preguntarse hacia el seno de la comunidad científica acerca del alcance efectivo del darwinisimo dentro de la biología. En este trabajo analizamos este supuesto intentando responder, al menos de una manera aproximativa, la pregunta: ¿es darwinista la biología en la actualidad? A estos fines, consideramos algunos de los principales aportes que suelen asignarse al darwinismo en las ciencias de los sistemas vivos: el análisis y centro en la diversidad, un origen único de los sistemas vivos, la incorporación del azar y el reconocimiento de las causas proximales. En términos... |
| Tipo: Journal article |
Palavras-chave: Causas próximas; Darwinismo; Diversidad biológica. |
| Ano: 2009 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2009000400003 |
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| RECABARREN,OMAR P; PINO,MARIO; CID,INÉS. |
| Fourteen dental and bone parts of a horse excavated from the Pilauco paleontological site, Osorno (40°39' S-73°07' W) are analysed and interpreted. This site was formed in association with a peat bog located on the banks of the old Damas River and has conserved abundant late Pleistocene mammalian fauna and flora materials. A date of 11457 ± 140 14C yrs B.P. was obtained from a molar and agrees with our stratigraphic age model. We have identified the fossils as pertaining to the species Equus (Amerhippus) andium, which confirms its presence in central-south Chile. Furthermore, the recorded geographic location indicate that the metapodial adaptations of the specimens previously described agree with the reconstructed late Pleistocene landscape of Pilauco,... |
| Tipo: Journal article |
Palavras-chave: Equus; Equus (Amerhippus) andium; Late Pleistocene; Pilauco. |
| Ano: 2011 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2011000400006 |
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| VILLALOBOS,L.; PARRA,O.. |
| From November 1996 to October 1997, the river basins of five humic lakes on Chiloé Island were studied monthly: Lakes Natri, Tepuhueico, Tarahuín, Huillinco and Cucao. The objective of this study was to know the catchment area, river basin and the main physical, chemical and biological characteristics of these humic lakes. The trophic status, the actual loading, and the mass balances of phosphorus and nitrogen were determined in relation to anthropogenic activities. Lakes Cucao and Huillinco were characterized by a marine influence. All the lakes had brown coloured waters, caused by humic substances, which limit their transparency. Lake Natri was the deepest (58 m), whereas Lake Tepuhueico had the shallowest depth (25 m). Total phosphorus and nitrogen... |
| Tipo: Journal article |
Palavras-chave: Cuenca hidrográfica; Caracterización limnológica; Lagos húmicos; Chiloé; Sur de Chile. |
| Ano: 2003 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2003000400003 |
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| Kenagy,G.J.; Vásquez,Rodrigo A.; Nespolo,Roberto F.; Bozinovic,Francisco. |
| We present an analysis of time and energy allocation in a day-active caviomorph rodent, the degu, Octodon degus, in central Chile. We quantified components of surface activity in the field on a daily basis in individual degus near the time of the summer solstice, when conditions of heat and aridity were also at a seasonal extreme, in order to answer the following questions. Does the absolute time available for surface activity limit performance? Does the allocation of time and energy for locomotion place a functionally significant limitation on overall energy balance and performance? Degus spent about 2/3 of their above-ground time foraging; they remained stationary about 88 % of the time, walked around slowly about 10 %, and were running rapidly from one... |
| Tipo: Journal article |
Palavras-chave: Time; Energy; Activity; Central Chile. |
| Ano: 2002 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2002000100014 |
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| ACEBES,PABLO; TRABA,JUAN; PECO,BEGOÑA; REUS,MARÍA L; GIANNONI,STELLA M; MALO,JUAN E. |
| Defining plant communities in desert zones is difficult due to large scale homogeneity and small scale heterogeneity, thus making provision of systematic information for conservation decisions problematic. We analysed plant communities of the most arid sector of Monte Desert for structure, plant composition and environmental variables. Small-scale variables such as slope, rock cover, bare ground and litter, as well as large-scale ones such as species diversity, composition and similarity within and between sites were included. Analyses of floristic composition showed the difficulty of segregating distinct communities due to high internal heterogeneity and overlap between the different sites. Only mesquite woodlands, a community situated at the extreme of... |
| Tipo: Journal article |
Palavras-chave: Arid environment; Heterogeneity; Shrubland; Similarity; Species richness. |
| Ano: 2010 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2010000300007 |
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| PADRÓN,EVA; NAVARRO-CERRILLO,RAFAEL M. |
| The significance of field work in remote sensing studies when applied to large areas has often been underestimated. The combination of specific forest inventories for the estimation of aboveground biomass in large dry tropical forest areas with remote sensor data has scarcely been explored to date. In this work, a systematic, stratified forest inventory involving 100 X 100 m square plots in an area of Peruvian Prosopis pallida dry forest, roughly one million hectares in size in the Piura province (Peru) has been compiled. The inventory encompassed the principal silvicultural variables defining the ecosystem studied, which were used in allometric equations for the different species, genera and plant associations in the area in order to estimate the amount... |
| Tipo: Journal article |
Palavras-chave: Prosopis pallida; Landsat 7 ETM+; Vegetation indices; Biomass estimation. |
| Ano: 2007 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2007000100004 |
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| LESCRAUWAET,ANNE-CATHERINE; GIBBONS,JORGE; GUZMAN,LEONARDO; SCHIAVINI,ADRIAN. |
| Abundance of Commersons dolphin, Cephalorhynchus commersonii (Lacépède 1804), in the eastern portion of the Strait of Magellan was estimated by means of aerial transects in autumn (June 1996). Using a helicopter at 100 m altitude and 129 km h-1, 58 sightings representing 98 animals (average group size Es = 1.7, SD = 0.13) along 818.6 km of linear transects were recorded. Data analysis with "Distance" software gave a density estimation of 0.34 ind km-2 (CV = 0.27) and a population size of 1,206 (95% CI 711-2,049 individuals). Commersons dolphin showed a habitat preference for the narrows, compared to open waters in the study area. |
| Tipo: Journal article |
Palavras-chave: Commersons dolphin; Cephalorhynchus commersonii; Strait of Magellan; Line transect sampling; Habitat preference. |
| Ano: 2000 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2000000300010 |
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| Registros recuperados: 845 | |
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