What is a primary role of meiosis in sexually reproducing organisms?

The primary role of meiosis in sexually reproducing organisms is to generate genetic variability. This process involves two rounds of division that result in four haploid cells, each of which carries a unique combination of genes due to events such as crossing over and independent assortment. These mechanisms increase genetic diversity within a population, which is essential for evolution and adaptation to changing environments.

While maintaining chromosome number is an important function of meiosis in that it halves the diploid chromosome number to produce haploid gametes, this is more of a consequence of the process rather than its primary role. Similarly, while duplicating genetic material occurs during the initial phase of meiosis, it does not capture the essence of what meiosis contributes to sexual reproduction as it is not the distinguishing factor of meiosis. Ensuring haploid cells is indeed a crucial feature of meiosis, but the fundamental impact of this process lies in how it contributes to genetic variability in offspring, enhancing their chances of survival and reproduction in diverse environments.