1. Mutation: Mutations are changes in the DNA sequence. These changes can be spontaneous or caused by environmental factors. While most mutations are neutral or even harmful, some can be beneficial and lead to new traits. Over time, the accumulation of mutations contributes to the variation within the human gene pool.
2. Sexual Reproduction: Humans reproduce sexually, combining genetic material from two parents. This process shuffles genes through the processes of independent assortment of chromosomes and crossing over during meiosis, creating unique combinations of genes in each offspring. This constant mixing of genes leads to diverse genotypes and phenotypes within a population.
