BMAR - Artigos em revistas internacionais
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Browsing BMAR - Artigos em revistas internacionais by Author "Almada, Frederico José Oliveira de"
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- A rapid and inexpensive molecular technique to discriminate the north-eastern Atlantic and Mediterranean Atherina species and its potential applications in ecology and larval identificationPublication . Almada, Vítor Carvalho; Francisco, Sara Martins; Rosa, Inês; Domingues, Vera dos Santos; Cabral, Henrique; Almada, Frederico José Oliveira de; Henriques, Miguel; Robalo, Joana IsabelThis note describes a rapid and inexpensive Restriction Fragment Length Polymorphism technique to discriminate all species of Atherina (Pisces: Atherinidae) of the north-eastern Atlantic and the Mediterranean. This technique is based on digestion of a fragment of the 12S ribosomal RNA (12SrRNA) gene region of mitochondrial DNA with restriction enzymes that recognize species-specific nucleotide sites. The three currently recognized species in the area, as well as two additional forms awaiting formal description, can be discriminated using a set of four endonucleases. We argue that this simple and fast technique may be of great help in the identification of young stages and in ecological surveys.
- Unexpected high genetic diversity at the extreme northern geographic limit of Taurulus bubalis (Euphrasen, 1786)Publication . Almada, Vítor Carvalho; Almada, Frederico José Oliveira de; Francisco, Sara Martins; Castilho, Rita; Robalo, Joana IsabelThe longspined bullhead (Taurulus bubalis, Euphrasen 1786) belongs to the family Cottidae and is a rocky shore species that inhabits the intertidal zones of the Eastern Atlantic since Iceland, southward to Portugal and also the North Sea and Baltic, northward to the Gulf of Finland, with some occurrences in the northern Mediterranean coasts eastward to the Gulf of Genoa. We analysed the phylogeographic patterns of this species using mitochondrial and nuclear markers in populations throughout most of its distributional range in west Europe. We found that T. bubalis has a relatively shallow genealogy with some differentiation between Atlantic and North Sea. Genetic diversity was homogeneous across all populations studied. The possibility of a glacial refugium near the North Sea is discussed. In many, but not all, marine temperate organisms, patterns of diversity are similar across the species range. If this phenomenon proves to be most common in cold adapted species, it may reflect the availability of glacial refugia not far from their present-day northern limits.