Genetic Variability and Evolution

  • F. García-Arenal
  • A. Fraile
  • J. M. Malpica


Variation is an intrinsic property of living entities. New genetic variants are generated as organisms reproduce and their frequencies in populations may change with time. This temporal change of the genetic structure of the population of an organism is the process of evolution. The study of evolution has two main goals. One is to clarify the evolutionary history of organisms, the other is to understand the mechanisms of evolution. Much work has been done in the recent past and also reviewed to clarify the evolutionary history and the resulting taxonomic relationships of viruses, including plant viruses (Gibbs et al., 1995; Gibbs et al., 1997; Morse, 1994; Zanotto et al., 1998). This will not be addressed in this chapter which instead is focused on the other main goal - mechanisms of evolution.


Tobacco Mosaic Virus Cucumber Mosaic Virus Plant Virus Virus Population Virus Evolution 
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© Springer Science+Business Media New York 1999

Authors and Affiliations

  • F. García-Arenal
  • A. Fraile
  • J. M. Malpica

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