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| Almaca, Carlos. |
| Coming from Oriental Asia and Siberia, the Cyprinidae reached the Iberic Peninsula probably at the end of the Oligocene. Their populations bore speciation processes which led to the formation of a fauna rich in endemic species and subspecies. Populations of two of the genera Barbus and Pseudophoxinus reached Northwestern African forming there several endemic species. Concerning the speciation forms, it is probable that the allopatric form, whether by foundation effect or by subdivision, played an important part. Pyrenees and Mediterranean Sea settled probably efficient barriers for the Iberic Cyprinidae isolation. The present geographical repartition of Cyprinidae in Iberic Peninsula suggests that altitude lines and glaciations which reached the north of... |
| Tipo: Text |
Palavras-chave: Portugal; Spain; Cyprinidae; Biogeography; Speciation. |
| Ano: 1976 |
URL: http://archimer.ifremer.fr/doc/1976/publication-1997.pdf |
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| Prance,Ghillean T. |
| Neste trabalho são apresentados padrões de distribuição geográfica de espécies de Chrysobalanaceae, Caryocaraceae, Dichapetalaceae e Lecythidaceae. Seis padrões são discutidos: espécies amplamente distribuidas, polimórficas (ochlospecies) onde a variabilidade morfológica não conduzia a especiação; distribuição disjunta onde a diferenciação em espécie não ocorreu; especiação através de separação histórica tal como isolamento durante o Pleistoceno; generos com grupos de espécies muito relacionadas, que não podem ser subdivididos em subgeneros; utilizou-se diagramas de isolinhas de espécies para determinar o centro de diversidade dos gêneros; e, espécies de savanas que inicialmente tinham distribuição contínua e que atualmente são isoladas. A análise de... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Distribution patterns; Speciation; Disjunct distribution; Refugia. |
| Ano: 1987 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33061987000300003 |
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| Menken, Steph B.J.. |
| Gel electrophoretic techniques were used to analyse patterns of variation at 12 genetic loci within and among species of the Ectoedemia subbimaculella group from western Europe. Geographically separated conspecific populations were similar to one another genetically, with the exception of E. subbimaculella where the malate dehydrogenase locus exhibited clinal variation. Genetic differences among species often concerned loci that were monomorphic or slightly polymorphic within populations. Three of the species could not be diagnosed by their allozyme content; allele distribution patterns at some loci suggest that speciation took place recently and did not involve a genetic bottleneck. Phylogenetic trees constructed from allozyme data paralleled closely the... |
| Tipo: Article / Letter to the editor |
Palavras-chave: Allozyme variation; Biochemical genetics; Taxonomy; Speciation; Insecta. |
| Ano: 1990 |
URL: http://www.repository.naturalis.nl/record/503975 |
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| Michel, Pierre; Boutier, Bernard; Herbland, Alain; Averty, Bernard; Artigas, Lf; Auger, Dominique; Chartier, E. |
| The arsenic (As) cycle in the marine environment is known to be sensitive to biological activity. Within the scope of the National Coastal Oceanography Program, we undertook a specific study of the behaviour of this element in a water column on the continental shelf of the Bay of Biscay off the Gironde estuary during two oceanographic cruises conducted in May 1994 and May 1995. Various chemical forms were measured: arsenite (As3), at-senate (As5), monomethylarsenic (MMA), dimethylarsenic (DMA) and dissolved total As after ultraviolet mineralization. The net flux of total As from the Gironde estuary was evaluated as well as its effect on the concentration in surface marine waters. The vertical profiles in the coastal zone during a period of active primary... |
| Tipo: Text |
Palavras-chave: Arsenic; Phytoplankton; Speciation; Gironde plume; Biscay Bay. |
| Ano: 1998 |
URL: http://archimer.ifremer.fr/doc/1998/publication-851.pdf |
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| Gonzalez, Jean-louis; Dange, Catherine; Thouvenin, Benedicte. |
| In estuarine environment, cadmium has a nonconservative behavior. It can be present under various species: dissolved (mineral and organic complexes), colloidal and particulate forms (adsorbed, precipitated), or integrated by various mechanisms in the organisms. This distribution is the result of processes (physical, chemical and biological) which are controlled by many factors (salinity, pH, Eh, nature and concentration of suspended matter, primary production). Geochemical modeling is a very useful approach to understand the dynamics of this type of contaminant, especially in the complex systems which are the estuaries. A speciation model was used to simulate the measurements taken (dissolved and particulate Cd) during various cruises carried out in the... |
| Tipo: Text |
Palavras-chave: Cadmium; Estuary; Speciation; Modeling; Surface complexation; Cadmium; Estuaire; Spéciation; Modélisation; Complexation de surface. |
| Ano: 2001 |
URL: https://archimer.ifremer.fr/doc/00480/59120/61749.pdf |
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| Dange, Catherine. |
| Most of trace elements have a non conservative behavior in estuarine environments. It is the case of cadmium, cobalt and caesium for which the fate in estuarine and coastal zones is largely controlled by their distribution between water and suspended particles, which generally have high residence times or can be definitely deposited in these areas. Metallic contaminants and radionuclides can be present under various species : dissolved (mineral and organic complexes), colloidal and particulate forms (adsorbed, precipitated) or integrated by various mechanisms in the organisms. Such distributions are the result of processes (physical, chemical, biological) which are controlled by many factors (ionic strengh, pH, Eh, major cations concentration, nature and... |
| Tipo: Text |
Palavras-chave: Modeling; French estuaries; Caesium; Cobalt; Cadmium; Radionuclides; Trace metals; Speciation; Modélisation; Estuaires français; Cesium; Cobalt; Cadmium; Radionucléides; Métal trace; Speciation. |
| Ano: 2002 |
URL: http://archimer.ifremer.fr/doc/2002/these-183.pdf |
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| Pattiny, S.. |
| Contemporary distributions of Panurginus species and subspecies in Europe (Apoidea: Andrenidae: Panurginae) The largest number of Old World Panurginus Nylander, 1848 species is distributed in the West- Palaearctic. The genus is absent in Africa and rather rare in the East-Palaearctic. Warncke (1972, 1987), who is the main author treating Palaearctic Panurginae in the last decades, subdivided Panurginus into a small number of species, including two principal taxa admitting for each a very large number of subspecies: Panurginus brullei (Lepeletier, 1841) and Panurginus montanus Giraud, 1861. Following recent works, the two latter are in fact complexes of closely related species. In the West-Palaearctic context, distributions of certain species implied in... |
| Tipo: Article in monograph or in proceedings |
Palavras-chave: Panurginae; Biogeography; West-Palaearctic; Speciation; Glaciation; 42.75. |
| Ano: 2003 |
URL: http://www.repository.naturalis.nl/record/219862 |
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| HEYER,W. RONALD; REID,YANA R.. |
| The frog Leptodactylus fuscus is found throughout much of South America in open and disturbed habitats. Previous study of genetic differentiation in L. fuscus demonstrated that there was lack of genetic exchange among population units consistent with multiple species, rather than a single species. We examine advertisement vocalizations of L. fuscus to determine whether call variation coincides with genetic differentiation. Calls were analyzed for 32 individual frogs from 25 localities throughout the distributional range of L. fuscus. Although there is variation in calls among geographic samples, call variation is not concordant with genetic variation or geographic distance and the call variation observed is less than that typically found among other... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Advertisement calls; Leptodactylus fuscus; Speciation. |
| Ano: 2003 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652003000100006 |
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| Parmentier, E; Lagardere, Jean-paul; Vandewalle, P; Fine, M. |
| Because of pelagic-larval dispersal, coral-reef fishes are distributed widely with minimal genetic differentiation between populations. Amphiprion akallopisos, a clownfish that uses sound production to defend its anemone territory, has a wide but disjunct distribution in the Indian Ocean. We compared sounds produced by these fishes from populations in Madagascar and Indonesia, a distance of 6500 km. Differentiation of agonistic calls into distinct types indicates a complexity not previously recorded in fishes' acoustic communication. Moreover, various acoustic parameters, including peak frequency, pulse duration, number of peaks per pulse, differed between the two populations. The geographic comparison is the first to demonstrate 'dialects' in a marine... |
| Tipo: Text |
Palavras-chave: Speciation; Dialect; Geographic variation; Pomacentridae; Sound production. |
| Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-3630.pdf |
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| Vanzolini,Paulo Emilio. |
| Gymnodactylus amarali Barbour, 1925, was previously considered to be a subspecies of G. geckoides, with a wide distribution in the Brasilian cerrados. Examination of a specimen from Alto Parnaíba, Maranhão, near the type locality (Engenheiro Dodt, Piauí), indicates that it is a proper species, apparently limited to the upper Parnaíba basin. The form previously identified as G. geckoides amarali is described as a new species, G. carvalhoi, type locality Ipueiras, State of Tocantins, thus diagnosed: color pattern plain or, more often, with moderately contrasted ocelli; dorsal tubercles in 13 - 16 poorly organized longitudinal rows (mode 14, 72%); 31 - 49 tubercles in a paramedian row; 17 - 22 transverse rows of ventral scales; 13 - 18 infradigital lamellae... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Speciation; Lizards/systematics. |
| Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652005000400003 |
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| Zefa,Edison. |
| Three isolated populations of the cricket Endecous itatibensis Rehn, 1918 had been analyzed to test the hypothesis of divergence in the calling song estridulation and to discuss its implications in the speciation process. The song registers were obtained from specimens in Corumbataí, Piraciacaba and Itatiba cities, state of São Paulo, Brazil. In the three analyzed populations, calling songs are composed by pairs of notes. Specimens from Corumbataí emit composed phrases with 3 to 18 pairs of notes, while those of Piracicaba and Itatiba have 1 to 3 pairs of notes. Inter- and intrapopulational variability in the frequencies of acoustic signals were detected. While recording the calling songs, other stridulations were registered, possibly from species of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cricket; Bioacoustics; Acoustic competition; Stridulation; Speciation. |
| Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0073-47212006000100002 |
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| Bustamante, Paco; Lahaye, V; Durnez, C; Churlaud, C; Caurant, Florence. |
| Total (T-Hg) and organic (O-Hg) mercury concentrations and tissue distribution were examined in 20 species of cephalopods (n = 278) from the north eastern Atlantic waters, i.e. from the Bay of Biscay to the Faroe Islands. Concentrations of T-Hg in whole cephalopods showed elevated variations among species, i.e. from 40 to 3560ng g(-1) dwt, but a low variability within each species (mean CV%=39%). With the exception of oceanic squids, the digestive gland globally displayed higher T-Hg concentrations than the remaining tissues. In contrast, O-Hg concentrations determined in selected species were generally higher in the remaining tissues. Despite higher T-Hg concentrations, the digestive gland weakly contributed to the total body burden of both T-Hg and O-Hg... |
| Tipo: Text |
Palavras-chave: Cuttlefish; Octopus; Squid; Body distribution; Speciation; Bioaccumulation. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-1873.pdf |
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| Gonzalez, Jean-louis; Thouvenin, Benedicte; Dange, Catherine; Chiffoleau, Jean-francois; Boutier, Bernard. |
| The role of particles in the fate and speciation of trace metals in macrotidal estuaries was studied using a surface complexation model (MOCO). Cadmium was selected as the target metal contaminant due to its reactivity in estuaries: cadmium behavior is mainly controlled by heterogeneous processes (sorption/desorption) related to salinity and suspended matter gradients. Various scenarios of suspended matter distribution according to salinity were simulated. The impact of surface properties (specific surface area, density of surface sites, acido-basic properties, and complexation constant) was evaluated using data collected on particles from the Gironde, Loire, and Seine estuaries. Our results show that particle surface properties, evaluated on the basis... |
| Tipo: Text |
Palavras-chave: Turbidity maximum; Speciation; Sorption; Particles; Modeling; Macrotidal estuaries; Cadmium. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-2005.pdf |
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