Environmental factors are really important because they help shape how much genetic variety there is in living things. This genetic variety is key for evolution and adapting to new changes. The main parts of genetic variability are mutations, polymorphisms, and genetic diversity.

1. Mutations

Mutations are random changes in DNA. Sometimes, the environment can cause more mutations to happen. For example:

• Radiation: Being exposed to UV radiation can cause about 1 in 1,000 building blocks of DNA (nucleotides) to change.
• Chemicals: Things like benzene can make mutation rates go up by 2 to 3 times in certain plants and animals.

2. Polymorphisms

Polymorphisms are genetic changes that help make different forms within a group of organisms. Environmental factors that can lead to polymorphisms include:

• Natural Selection: When some traits are better suited for certain environments, they can stick around in a population. For instance, during the Industrial Revolution, most peppered moths were dark-colored in polluted areas because they blended in better with their surroundings.
• Gene Flow: When new individuals move into a population, they can bring new genetic traits. Research shows that areas with more immigration can have up to 10% more genetic variety.

3. Genetic Diversity

Genetic diversity is super important for the survival of species. It helps populations adapt to changes in their habitats. Some interesting facts are:

• Inbreeding Depression: Groups with less genetic diversity may have a 25% higher chance of dying out when environmental changes occur.
• Reservoir of Alleles: Populations that are more genetically diverse have a better chance of surviving diseases, with a 70% survival rate in those groups compared to only 30% in less diverse ones.

In conclusion, environmental factors boost genetic variety through mutations, polymorphisms, and increasing genetic diversity. This process is essential for the survival and adaptation of species.