ABSTRACT
Genomes are dynamic molecular entities that evolve over time due to the cumulative effects of mutation, recombination, and selection. Biological, or genetic, information is a fundamental concept of bioinformatics. This chapter provides an overview of the processes giving rise to the dynamics of evolutionary change at the molecular level. It primarily focuses on biological mechanisms relevant to the evolution of genomic sequences encoding polypeptide chains. Charles Darwin identified three major features of the process that occur in an endlessly repeating cycle: generation of heritable variation by random mutation at the level of the genotype, natural selection acting on the phenotype, and differential reproductive success. Protein families arise mainly through the mechanism of gene duplication. In the 1930s, J. B. S. Haldane and Hermann Muller were the first to recognize the evolutionary significance of this process. Evolutionary relationships between members of protein families can be classified according to the concept of homology.
