The results of the individual-based model (ps = 0.025, μ = 0.03, s = 0.015, N = 3,000, AL = 200). The dashed line stands for the species without cell senescence; the solid line stands for the species that employs cell senescence. The two species were in separate environment. (A) Average number of deleterious mutations per diploid genome. (B) Mean population fitness. (C) Average clonal age. The average clonal age of individuals in the species employing cell senescence fluctuates around 50.