/sci/ - Science & Math

Your argument doesn't make any sense. What you're essentially saying is "if A is good, why don't we see B, when B directly hampers A".
Evolution is largely driven through the exchange of multiple sets of genetic information, i.e. when two individuals with different genomes breed to produce offspring with a variable genome made up of a random combination of the parents' genes.
Self-replication as a process is much less effective at evolution, because the only factor driving genetic variation between generations in this instance are chance mutations.
If evolution is an important factor in determining which species continue to live, we would expect to see that the process which results in increased genetic variability (i.e. Sexual intercourse between multiple individuals) be found in more species, especially more complex ones. And we do see this.