Though evolution by natural selection is classically thought of as the speciation and adaptation of complex Eukaryotic life, when applied to Pathogens including Prokaryotes (Bacteria), simple Eukaryotes (Protist etc.) and Viruses, there is mounting evidence that these three groups undergo evolution by natural selection in ways that alter their virulence, symptoms and infectivity to increase their fitness.
Though we can apply the principles of evolution by natural selection to the rapid changes in phenotype expression in pathogenic agents, their mechanisms for change - and the implications of these mechanism - are very different. In terms of sexually reproducing complex Eukaryotes, classical evolution by natural selection is a gradual change.
Though we can apply the principles of evolution by natural selection to the rapid changes in phenotype expression in pathogenic agents, their mechanisms for change - and the implications of these mechanism - are very different. In terms of sexually reproducing complex Eukaryotes, classical evolution by natural selection is a gradual change.