Fig 2.

The competitive fitness of unisexually proficient and deficient strains is environment specific. The results of competition between the wild type and mutant isolates on three media are shown in the top panels. The average proportions (%) of the wild type per environment per mutant genotype from the center of the coincubation spot for three replicates are shown. The whiskers show standard error. The dotted line marks the proportion of the wild type expected under the null hypothesis (50%). We tested two independent deletion mutants each for the STE7, MAT2, and SPO11 genes. We analyzed whether the two independent mutants of the same gene behaved similarly in a given environment using 2-factor analysis of variance (see Table S1 in the supplemental material) to test the effects of the variables and their interaction on the proportion of the wild type. The bottom panel provides the proportions (%) of the wild type when coincubated in competition with the respective deletion mutants on three different media. The binomial two-sample proportion test was used to test for significant deviation from equality (50%) in each competition assay conducted in a given environment (see Table S2 in the supplemental material).