All three processes underlying the combinational variability act independently from each other, creating a huge variety of all kinds of genotypes. Genes with combinational variability do not change, but their new combinations appear, which leads to the appearance of organisms with new phenotypes, which can be both useful and harmful in these living conditions of the body.
Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.