Is crossing over important for the diversity of biological evolution?
The Sexual reproduction and the recombination of linked genes (crossing over) are, along with mutations, the main instruments of biological variability. The Sexual reproduction allows many combinations between genes situated in different chromosomes. The Crossing over, however, is the only means to provide recombination of alleles located in a same chromosome. The Crossing over probably emerged and has been maintained by the evolution because of its importance to biological diversity.