Why Rely On Mutations?
Darwinian Evolution attempts to explain the origin of genetic information other than by intentional creation, therefore variability must theoretically have existed before cellular mechanisms were present.
Purposeful genetic variability implies intelligent design, and Darwinian Evolution is based on atheistic philosophy
"Mutation is the ultimate source of all genetic variation found in natural populations and the only new material available for natural selection to work on." Ernst Mayr. Populations, Species, & Evolution. 1970, p.102
Replication makes an exact copy. Recombination makes changes.