Taxes evolutives i evolució de gens i genomes Authors Lluís Serra Camó Antonio Fontdevila Abstract We introduce the concept of evolutionary rate and discuss its significance and application in the study of systematic human-induced alterations of natural habitats. The evolutionary changes in nucleotide or amino acid sequences and the dynamics of substitution rates are analysed, introducing the concept of molecular clock and the neutral theory as a null hypothesis to interpret evolutionary rates. The use of nucleotide or amino acid sequences to establish evolutionary relationships between species is also discussed, giving an example of the construction of a phylogenetic tree and a statistical method to determine tree reliability. We then proceed to consider those genetic changes that make us different from the chimpanzee, our closest relative, and to discuss the mechanisms responsible of genome-size evolution, in particular intragenic duplication and gene elongation, exon shuffling, gene duplication, and genome duplication. Finally, we discuss the evolutionary significance of transposable genetic elements. Downloads Download data is not yet available. Downloads Text complet (Català) Published 2008-11-06 Issue 57, 2006 : L'ensenyament de la biologia en l'ESO i el batxillerat / Josep Clotet i Lluís Serra, editors Section Actualització dels coneixements License The intellectual property of the articles belongs to the respective authors. At the time of submitting the articles to Treballs de la Societat Catalana de Biologia, authors accept the following terms: — Authors assign to the SCB (a subsidiary of the Institut d’Estudis Catalans) the rights of reproduction, public communication (including communication through social networks) and distribution of the articles submitted for publication to Treballs de la Societat Catalana de Biologia, in any form and medium, including digital platforms. The Publications Committee reserves the right to accept or refuse submitted articles and the right to make any editorial changes it deems appropriate. If the suggested changes are accepted by authors, they should re-submit the article with such changes. — Authors answer to the SCB for the authorship and originality of submitted articles. In other words, authors assure that submitted articles do not contain fragments of works by other authors or fragments of their own previously published works; that the content of articles is original, and that the copyright of third parties is not infringed upon. Authors accept this responsibility and undertake to hold harmless the SCB for any loss or damage resulting from non-compliance with this obligation. Furthermore, they should include a statement in articles submitted to the journal regarding their responsibility for the content of the articles. — Authors are responsible for obtaining permission for the reproduction of all graphic material included in articles, and they should moreover ensure that images, videos, etc., have been created with the consent of the individuals appearing in them, and that material belonging to third parties is clearly identified and acknowledged as such within the text. Likewise, authors should provide the respective consents and authorisations to the SCB when submitting articles. — The SCB is exempt from any liability arising from the possible infringement of intellectual property rights by authors. In all cases, it undertakes to publish corrections, clarifications, retractions and apologies, if necessary. — Unless otherwise stated in the text or in the graphic material, the contents published in the journal are subject to an Attribution - NonCommercial - NoDerivs 3.0 Spain (by-nc-nd) license from Creative Commons, the full text of which may be consulted at https://creativecommons.org/licenses/by-nc-nd/3.0/es/deed.en. Therefore, the general public is authorised to reproduce, distribute and communicate articles as long as their authorship and publishing entity are acknowledged, and no commercial use is made of them nor derivative work produced from them. — The journal is not responsible for the ideas and opinions expressed by the authors of published articles.
