During certain evolutionary scenarios, such as genetic sweeps and range expansions, the driving lineages have an increased competitiveness or experience an absence of competition, which results in a higher tolerance of deleterious mutations. We have named this phenomenon, during which individuals have more freedom to explore their fitness landscape, the “Free-for-All” effect (FFA). We present evidence for the free-for-all effect and discuss some of its implications for evolutionary science. This document summarizes work that we are preparing for publication.

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