1. Variation: Individuals within a population must have differences in their traits. This could be anything from size, color, behavior, or resistance to disease.
2. Inheritance: These variations must be heritable, meaning they can be passed down from parents to offspring. This ensures that advantageous traits are more likely to be seen in future generations.
3. Differential survival and reproduction: Individuals with certain traits are more likely to survive and reproduce than others in a given environment. This means those traits are more likely to be passed on to the next generation.
These three factors working together drive the process of natural selection, leading to changes in the genetic makeup of a population over time.
