Statistical analysis
Life table data were analyzed according to the age-stage, two-sex life theory (Chi 1988) using the TWOSEX-MSChart software (Chi, 2015). Four parameters, the net reproductive rate (R 0), the intrinsic rate of increase (r ), the finite rate of increase (λ ) and the mean generation time (T ) were calculated. Age-specific survival rate and fecundity were also calculated using the TWOSEX-MSChart, and visualized using SigmaPlot software version 14.0 (Systat Software Inc., Chicago, IL). The means and standard errors of the parameters were estimated using bootstrap method by 100,000 permutations, and were compared between the fresh and the pre-infected treatment using paired bootstrap test. The body size and duration of the four waveforms were pairwise compared between treatments by nonparametric Mann-Whitney U test using SPSS 19.0 software package.