Genetics is the very means of biodiversity. Biodiversity literally means the diversity (or variety) of living organisms. Genetics contributes to this through the variety of genes and adaptations that occur to different organisms in order to survive and even thrive in their environment. These adaptations result in different species, subspecies, and, with time, completely new organisms each specialized to live in a specific manner. As an example, cactuses evolved to survive in low water/high temperature environments when normal plants can’t. Without evolution, there would be no plants in the desert as they wouldn’t be able to survive the heat and drought.
The answer you are looking for, is a hypothesis, basically you are suggesting it, which means it is a hypothesis. I hope this answers your question, and good luck!
The parents are of genotype heterozygous dominant and homozygous recessive. Supposing the dominant allele is N and the recessive allele is n, one of the parents will be Nn while the other nn. The phenotypic (based on visible characteristics) ratio will be 1:1 for dom/rec and rec/rec