Mortality during and survival following diet treatments
To investigate the effects of diet and infection cue treatments on
survival throughout the experiment, we assessed mortality and survival
at three points: mortality during the 3-week feeding period, mortality
during the 2-day calling trial, and survival following calling effort
trials. To assess mortality during both feeding trials, the full model
included diet type, the average amount of food eaten, and the
interaction between the two as main effects and pronotum size as a
covariate. The full models for mortality during the calling trial and
survival following included diet type, infection cue, and the
interaction between the two as main effects and average amount of diet
eaten and pronotum width as covariates. Mortality during both feeding
trials and calling effort trials was assessed using generalized a linear
model with a quasibinomial distribution (to accommodate overdispersion
of the data) and survival following calling trials was analyzed using a
Cox proportional hazards regression model.