Understanding Evolution

Genetic variation

Without genetic variation, some of the basic mechanisms of evolutionary change cannot operate.

There are three primary sources of genetic variation, which we will learn more about:

  1. Mutations are changes in the DNA. A single mutation can have a large effect, but in many cases, evolutionary change is based on the accumulation of many mutations.

  2. Gene flow is any movement of genes from one population to another and is an important source of genetic variation.

  3. Sex can introduce new gene combinations into a population. This genetic shuffling is another important source of genetic variation.
Genetic shuffling
Genetic shuffling is a source of variation.


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