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docs/2_Theoretical_background/Theoretical-background.md

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 # Background
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-This section offers  a brief theoretical background on the rationale behind the genetic diversity indicators.
+This section offers background on the population genetics rationale behind the genetic diversity indicators. Population genetics is a science that has existed for more than 100 years.  It is based in the mathematics of inheritance and probability, and many thousands of experiments and observational studies. Because of these characteristics, it is a science with strong theoretical foundations and predictive ability. Genetic variation within species and their populations is shaped by four processes: mutation (new genetic diversity), genetic drift (loss of diversity due to chance in small populations), gene flow (genetic diversity from another population via movement with successful reproduction) and natural selection. The genetic diversity indicators described below focus on these processes.