Which of the mechanisms below increases the amount of genetic variations in a population?

Mutation

Mutation is the change of the species due to selection forces and thus results to adaptations. Adaptations are the result of evolution in different living organisms. This process occurs amazingly through gene mutation but it takes a very long period in time. Adaptation processes occur to help species survive and thrive in the ecological balance of life. Structural adaptations are physical features of an organism that adapted through time. 

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