Mutations play a big role in evolution. They create differences in the genes of living things, which is important for how species change over time. Here are the main types of mutations and what they do:

1. Point Mutations: These are small changes in just one part of the DNA. They can be split into three groups:

   • Silent Mutations: These don't change anything about the amino acids. They make up about 70% of point mutations.
   • Missense Mutations: These change one amino acid, which can change how a protein works. This group is around 25% of point mutations.
   • Nonsense Mutations: These create a signal for the protein to stop being made too early, often leading to proteins that don’t work. These make up about 5% of point mutations.

2. Insertions and Deletions (Indels): These mutations either add or take away pieces of DNA. They can mess up the way the gene is read, which can greatly change how a protein functions.

3. Duplications: In this type, parts of DNA get copied. This can create extra genes, which might lead to new abilities or functions. It is estimated that about 5-10% of differences between people come from duplications.

4. Inversions: This happens when a section of DNA flips around. This can change how genes work or how they mix with each other.

Effects on Evolution:

• Natural Selection: Most mutations, about 99%, don’t help or can even harm the organism. However, some mutations can be beneficial and help species adapt. For example, the ability to digest lactose came from a mutation that happened about 7,500 years ago in some human groups.

• Genetic Drift: Sometimes, changes happen by chance, especially in small groups of organisms. This randomness can affect how species evolve, and up to 30% of genetic differences can come from these chance changes over time.

In short, mutations are important because they create variety in genes. This variety greatly affects how species evolve and change.