The answer to your question is Competition
Sorry if I’m wrong
There have been 5 Mass Extinctions throughout Earth's history.
Most organisms are Diploid, and as a result, they will have received 2 copies of the chromosomes, or sets of chromosomes, from both their parents. This they will have 2 sets of Genes that will perform almost exact same process, except with different phenotypes.
These chromosomes need to be homologous, in order for new alleles and other genetic combinations to be made.
It is true Have a very nice day
