Table 2. Multiple comparisons of evolutionary rates among reproductive processes.

Reproductive process	Spermatogenesis	Sperm metabolism	Sperm motility	Capacitation	Acrosome reaction	Sperm-egg interaction
Spermatogenesis	–	0.88	0.06	0.30	0.86	0.0021 (**)
Sperm metabolism	0.05	–	0.06	0.64	0.54	0.0005 (**)
Sperm motility	0.002 (**)	0.15	–	0.028 (*)	0.08	0.13
Capacitation	0.75	0.25	0.025 (*)	–	0.96	0.0003 (**)
Acrosome reaction	0.05	0.93	0.18	0.21	–	0.024 (*)
Sperm-egg interaction	0.09	0.92	0.14	0.09	0.94	–

Average synonymous (dS) and non-synonymous (dN) substitutions were calculated for different groups. P-values above the diagonal represent pairwise comparisons of dN rates whereas P-values below the diagonal show comparisons of dS rates. (*) and (**) indicate statistical significance with a 95% and 99% confidence interval respectively.