Natural selection is a fundamental mechanism of evolution, which is the process of change in living organisms over successive generations. Natural selection was proposed by Charles Darwin and is driven by three key principles: variation, heredity, and differential reproductive success.
Variation: Within a population of organisms, there is genetic and phenotypic variation. Individuals within a population exhibit differences in their traits, such as size, color, or behavior. These variations arise from genetic mutations, genetic recombination during reproduction, and other sources of genetic diversity.
Heredity: Offspring inherit traits from their parents through the transmission of genetic information. Genes are passed down from one generation to the next, preserving the traits present in the parent organisms.
Differential Reproductive Success: In every generation, there is competition for limited resources, such as food, mates, and habitat. Not all individuals can survive and reproduce successfully. Some individuals possess traits that are advantageous in their environment, allowing them to survive better, reproduce more, or have more offspring that survive to reproductive age.