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116 años de la Revista Chilena de Historia Natural: Breve relato de dos antes y un después RChHN
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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20th century fluctuations in the abundance of siliceous microorganisms preserved in the sediments of the Puyuhuapi Channel (44° S), Chile RChHN
REBOLLEDO,LORENA; LANGE,CARINA B.; FIGUEROA,DANTE; PANTOJA,SILVIO; MUÑOZ,PRÁXEDES; CASTRO,RODRIGO.
We present a 100-year reconstruction of siliceous export production from sediments of the Puyuhuapi Channel (44° S, 70° W) in the Chilean fjords. We use accumulation rates and concentrations of diatoms and silicoflagellates, organic carbon (Corg) and biogenic opal (SiOPAL) as proxies of export production, and fluctuations in the contribution of freshwater diatoms as proxies of rainfall in the hinterland and river runoff. Box core sediments collected at two sites within the Puyuhuapi Channel were analyzed: Station 35 (at the head of the fjord; 56 m water depth) and Station 40 (in the middle of the Channel; 270 m water depth). Surface sedimentation rates were 0.75 cm yr-1 at Station 35 and 0.25 cm yr-1 at Station 40. SiOPAL content averaged ~ 4 % at both...
Tipo: Journal article Palavras-chave: Siliceous microorganisms; Diatoms; Sediments; Export production; Puyuhuapi Channel; Chilean fjords.
Ano: 2005 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2005000300009
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A critical view to explanations for the maximal value of 50 % of genetic recombination RChHN
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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A developmental approach to homology and brain evolution RChHN
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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A dichotomous species of Codium (Bryopsidales, Chlorophyta) is colonizing northern Chile RChHN
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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A hybrid zone of two toad sister species, Rhinella atacamensis and R. arunco (Anura: Bufonidae), defined by a consistent altitudinal segregation in watersheds RChHN
CORREA,CLAUDIO; MÉNDEZ,MARCO A; ARAYA,SERGIO; LOBOS,GABRIEL; PALMA,R. EDUARDO.
Delimiting the spatial extension of a hybrid zone is essential to understand its historical origin and to identify the geographical and/or environmental factors which delimit it. Rhinella atacamensis and R. arunco are two sister species which together inhabit Chile between 25° and 38° S. Their distribution limits coincide at about 32° S, where recently it was reported that they hybridize in a small watershed (Pupío creek). Although the genetic evidence suggests that these two species form a hybrid swarm, they are not mixed homogeneously in the entire watershed, but rather are spatially segregated: R. arunco is found in the lower part of the creek and R. atacamensis in the higher part. An extensive exploration north and south of 32° S revealed other...
Tipo: Journal article Palavras-chave: AFLP markers; Chile; Control region; Hybridization; Toads.
Ano: 2013 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2013000200001
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A los 150 años desde "El origen de las especies": ¿es darwinista la biología contemporánea? RChHN
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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A new geographic record of the endangered Darwin's fox Lycalopex fulvipes (Carnivora: Canidae): filling the distributional gap RChHN
D'ELÍA,GUILLERMO; ORTLOFF,ALEXANDER; SÁNCHEZ,PAMELA; GUIÑEZ,BASILIO; VARAS,VALERIA.
Tipo: Journal article
Ano: 2013 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2013000400010
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A new population of Darwin's fox (Lycalopex fulvipes) in the Valdivian Coastal Range RChHN
Farias,Ariel A; Sepúlveda,Maximiliano A; Silva-Rodríguez,Eduardo A; Eguren,Antonieta; González,Danilo; Jordán,Natalia I; Ovando,Erwin; Stowhas,Paulina; Svensson,Gabriella L.
Tipo: Journal article
Ano: 2014 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2014000100003
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A new record of Equus (Mammalia: Equidae) from the Late Pleistocene of central-south Chile RChHN
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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A quantitative analysis of forest fragmentation in Los Tuxtlas, southeast Mexico: patterns and implications for conservation RChHN
MENDOZA,EDUARDO; FAY,JOHN; DIRZO,RODOLFO.
Habitat loss is a critical threat to tropical biodiversity and its quantification constitutes a central conservation issue. Typically, assessments have been based on deforestation rates statistics. However, this overlooks the effects brought about by the spatial reconfiguration of the remaining habitat: fragmentation. We present an analysis of fragmentation in a Neotropical site aimed at: (a) devising a protocol for its quantification, (b) using such protocol to provide insights on the ecological consequences of fragmentation, (c) exploring its applicability to address the hypothesis that forest size-inequality decreases with elevation, an indicator of habitat accessibility. We applied the Gini coefficient (G) and the Lorenz curve to analyze fragment-size...
Tipo: Journal article Palavras-chave: Edge effect; Fragment shape; Gini coefficient; Lorenz curve; Tropical rain forest.
Ano: 2005 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2005000300008
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A rare but successful reproductive tactic in a social wasp (Hymenoptera:Vespidae): Use of heterospecific nests RChHN
DE SOUZA,ANDRÉ R.; SILVA,NEWTON J. J.; PREZOTO,FÁBIO.
Successful heterospecific use of abandoned nests has been reported in birds. Although the same behavior has been observed in wasps, the success of such tactic has not been demonstrated. We described two cases in which the social wasp Polistes versicolor successfully reared its brood in empty nests of the social wasps Mischocyttarus drewseni and Mischocyttarus cassununga (Hymenoptera: Vespidae). We showed that this is a rare but a viable reproductive tactic for both solitary and associative foundress. Unlike birds, which use heterspecific nests very similar to their own, wasps are able to use heterspecific nests that do differ from their own.
Tipo: Journal article Palavras-chave: Mischocyttarus cassununga; Mischocyttarus drewseni; Polistes versicolor.
Ano: 2012 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2012000300010
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A reassessment of the phytogeographic characterization of Temperate Pacific South America RChHN
SANTELICES,BERNABE; MENESES,ISABEL.
In 1980, a study of geographic distribution patterns and geographic affinities of benthic algae of temperate Pacific South America (5-55 ºS) provided a first characterization of these coasts. High endemism and limited floristic exchange with the Tropical Pacific and with islands in the South Pacific at various distances from the continent were two outstanding features of the marine flora. A partial blockage of species exchange partially accounted for a peculiar latitudinal pattern of species richness that increases with increasing latitudes. In contrast, there was reduced species richness in comparison with other climatically equivalent regions that have contact with more effective routes of migration. Over the last two decades, more than 30 taxonomic and...
Tipo: Journal article Palavras-chave: Benthic phytogeography; Isolation; Latitudinal patterns; Seaweeds; Temperate South America.
Ano: 2000 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2000000400005
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A study of the river basins and limnology of five humic lakes on Chiloé Island RChHN
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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A time-energy analysis of daytime surface activity in degus, Octodon degus RChHN
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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Abiotic alterations caused by forest fragmentation affect tree regeneration: a shade and drought tolerance gradient in the remnants of Coastal Maulino Forest RChHN
GUERRERO,PABLO C; BUSTAMANTE,RAMIRO O.
Plant regeneration is strongly determined by light and soil moisture differences between habitáis; both variables are modified by large-scale forest fragmentation. Several studies have indicated this alteration as the mechanism involved in tropical forest community change. The effects of fragmentation may be much more severe in Mediterranean and deciduous forests, because plant species in these forests show a stress tolerance tradeoff between shade and drought. Our study was performed in the deciduous fragmented Coastal Maulino Forest: Reserva Nacional Los Queules (RNLQ) and surrounding small fragments. We hypothesised that Aristotelia chilensis (shade intolerant but drought tolerant) should increase its regeneration in small patches as a consequence of...
Tipo: Journal article Palavras-chave: Ecological restoration; Forest fragmentation; Safe sites; Seed germination; Seedling establishment.
Ano: 2009 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2009000300008
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Abiotic gradients drive floristic composition and structure of plant communities in the Monte Desert RChHN
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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Aboveground biomass in Prosopis pallida (Humb. and Bonpl. ex Willd.) H. B. K. ecosystems using Landsat 7 ETM+ images RChHN
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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Abundance, distribution and feeding patterns of a temperate reef fish in subtidal environments of the Chilean coast: the importance of understory algal turf RChHN
PALMA,ÁLVARO T.; OJEDA,F. PATRICIO.
Cheilodactylus variegatus is an abundant carnivorous demersal reef fish that lives in the shallow subtidal of the north-central Chilean coast. Characteristically, these environments are dominated by kelp forests of Lessonia trabeculata. This species preys on a great variety of benthic invertebrates, and shows particularly high consumption rates on amphipod crustaceans. In our study, two widely separated populations of C. variegatus were considered (central and northern Chile). Individuals that form part of these populations show considerable differences in their distribution, abundance and trophic behavior. In the northern zone, the species is abundant and both juveniles and adults are distributed along the whole bathymetric gradient. This contrasts with...
Tipo: Journal article Palavras-chave: Cheilodactylidae; Shallow subtidal; Understory macroalgae; Carnivorous fish; Amphipods; Distribution; Abundance; Chile.
Ano: 2002 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2002000100018
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Abundance estimation of Commerson’s dolphin in the eastern area of the Strait of Magallan-Chile RChHN
LESCRAUWAET,ANNE-CATHERINE; GIBBONS,JORGE; GUZMAN,LEONARDO; SCHIAVINI,ADRIAN.
Abundance of Commerson‘s 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). Commerson’s dolphin showed a habitat preference for the narrows, compared to open waters in the study area.
Tipo: Journal article Palavras-chave: Commerson’s 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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