Figure 3.

Relative fertilization success for inbred (closed squares) and non-inbred (open squares) as either first- or second-to-mate males in two-male sperm competitions. Inbreeding significantly depresses both sperm defence and offence competitiveness (see figure 1 for the experimental design). Means presented ± standard error bars, numbers below error bars are sample sizes for each treatment. There are significant differences between inbred and non-inbred male sperm competition successes (p < 0.001), and a significant interaction with mating order (p = 0.006) (see table 2 for details).