How does meiosis achieve genetic diversity?

Meiosis produces 4 haploid daughter cells and is essential for forming gametes that contain one copy of each chromosome. Meiosis allows genetic diversity which gives rise to new combinations of genetic alleles so that offspring have varied phenotypes and natural selection occurs.Genetic diversity is achieved by 3 main mechanisms:1) Random chromatid assortmentWhen paired homologous chromosomes line up on the equator in metaphase 1, paternal and maternal chromatids are assigned to either cell randomly. Thus, each cell receives a random combination of maternal or paternal chromosomes.2) Crossing overIn order to keep homologous chromosomes paired, chiasmata form in which complementary sections of homologous chromosome cross over thus exchanging genetic material. This creates new allele combinations on the same chromosome. The further the genes are from the centre of the chromosome, the easier crossing over is and the more frequent recombination.3) Random fertilisationAny sperm can fertilise any ovum and thus again, a random combination of homologous chromosomes is produced in the zygote adding to genetic diversity.