Here's a breakdown:
* Alleles: These are alternative forms of a gene. For example, a gene for eye color might have an allele for blue eyes and an allele for brown eyes.
* Population: This refers to a group of individuals of the same species that can interbreed.
* Allele Frequencies: This describes how common each allele is within a population.
How Natural Selection Works:
1. Variation: Individuals within a population have different traits, often due to variations in their alleles.
2. Differential Survival and Reproduction: Some individuals with certain traits are better suited to their environment than others. They are more likely to survive, reproduce, and pass on their beneficial traits to their offspring.
3. Change in Allele Frequencies: Over generations, the alleles that contribute to advantageous traits become more common in the population, while less beneficial alleles become less common. This shift in allele frequencies reflects the ongoing process of natural selection.
In simpler terms: Natural selection is like a sorting process where individuals with traits that make them better at surviving and reproducing are more likely to pass their genes on to the next generation. Over time, this leads to changes in the genetic makeup of a population.
