Clonal interference

In asexual populations, when multiple beneficial mutations arise independently in different lineages, those lineages compete with each other rather than being able to be combined via Recombination. This slows the rate of adaptation because only one winning lineage ultimately fixes, and the rest are lost. The flip side of Muller’s ratchet: where the ratchet accumulates deleterious mutations without recombination, clonal interference wastes beneficial ones.