sábado, 14 de junio de 2008

Historical Biogeography

Historical biogeography is the study of the historical relationships among biotes using its geological history, and the distributional and phylogenetic (historical) characteristics from organisms that composed them. This conceptual approach is multidisciplinary because the biotes are subject to several factors that affect its structure and characteristics. Several authors has been defined Historical Biogeography (e. g. de Candolle, 1820; Croizat, 1964; Nelson & Platnick, 1981). However, these definitions were construyed using different and limited views about factors that affect the biotes evolution. So, an approach based only on phylogenetic relationships (e. g. Morrone & Crisci, 1995) of taxa within study areas is unreliable because geological process (an inherent factor in the evolution of life) is not reviewed. On the other hand, definitions based on tectonic and geological process ignore the historical relationships among taxa.
My approach about Historical Biogeography is based in the multidisciplinary study of historical relationships among areas using all the avaliable evidence (geological, distributional, and phylogenetic).Thus, In agree with Andersson (1996) in that "the task of Historical biogeography is to reveal and explain the history of biotas and their historical connections. Theses historical relationships among biotes is defined as the sharing of descendants of the same ancestor" and others factors.