Genetic variation is really important for natural selection and evolution. It gives nature the building blocks it needs to change over time.

Here are some key points to understand:

• Where Does Genetic Variation Come From?

  • Two main sources of genetic variation are mutations and sexual reproduction.
  • Mutations are small changes in our DNA. They happen about once in every million base pairs.

• What is Natural Selection?

  • Natural selection works on this variation.
  • Organisms that are better suited to their environment are more likely to survive and have babies.

• Some Interesting Numbers:

  • In a group of living things, helpful traits can spread quickly. For example, a useful trait might increase its presence by 30% over 20 generations.

In summary, genetic variation helps groups of living things adapt to changes in their environment through natural selection.