Evolution
Of the seven serotypes of this virus, A, C, O, Asia 1 and SAT3 appear to be distinct lineages; SAT 1 and SAT 2 are unresolved clades. The mutation rate of the protein-encoding sequences of strains isolated between 1932 and 2007 has been estimated to be 1.46 × 10-3 substitutions/site/year, a rate similar to that of other RNA viruses. The most recent common ancestor appears to have evolved about 481 years ago (early 16th century). This ancestor then diverged into two clades which have given rise to the extant circulating Euro-Asiatic and South African. This event occurred around 1800. Skyline plot analysis shows a population expansion in the early 20th century, which was then followed by a rapid decline in population size in the late 20th century.
At least seven genotypes of serotype Asia 1 are known.
Read more about this topic: Foot-and-mouth Disease
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“The more specific idea of evolution now reached is—a change from an indefinite, incoherent homogeneity to a definite, coherent heterogeneity, accompanying the dissipation of motion and integration of matter.”
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