Natural selection is the process by which organisms that are better adapted to their environment are more likely to survive and produce offspring. The two key components of natural selection are variation and competition:
Variation refers to the differences between individuals in a population. These differences can be due to genetic variation, environmental factors, or a combination of both.
Competition refers to the struggle between individuals for limited resources, such as food, water, and territory. The individuals that are better adapted to their environment are more likely to be successful in competition and produce offspring that are also well-adapted.
Over time, natural selection can lead to changes in the overall characteristics of a population. This process is known as evolution.