Exchange of genes in microbial evolution
2005/09/01 Elhuyar Zientzia Iturria: Elhuyar aldizkaria
Evolution advances when one or more of a species is formed. This evolution can be represented by an arborescent scheme, the tree of evolution. However, according to some biologists from the European Institute of Bioinformatics (IMD), evolution has other ways to advance. In fact, the tree model is not enough to explain the evolution of microbes, since it lacks connections between branches.
These connections consist of gene exchanges between microbes of different branches, since genetic material is easily exchangeable by organisms far from the evolutionary path. To confirm this, biologists have developed and implemented a method that seeks those exchanges of 'horizontal' genes. Among the microbes analyzed, 90,000 losses and 40,000 exchanges have been found. They consider that horizontal gene sharing is a very important process in microbial evolution. This process converts the evolutionary tree into a network that can connect very distant branches.
