Figure 5

Predictors of nest success for biparental species under uniparental incubation. (a–c) Probability of nest success (hatching of at least one egg) as a function of (a) the start of uniparental incubation within the incubation period (expressed as the % of the species’ incubation period that had passed when uniparental incubation started, (b) the duration of uniparental incubation, and (c) the median daily nest attendance during uniparental incubation. Circles represent means for intervals spread evenly across the range of x-values; circle size reflects sample size. The solid lines depict the model-predicted relationships, the shaded area the 95% credible intervals based on the joint posterior distribution of 5,000 simulated values generated by the ‘sim’ function in R⁴¹; the predicted relationships stem from a binomial mixed-effect model (Supplementary Table 7 in ref.²⁷), where the effect of the other predictors was kept constant. N = 50 nests with uniparental incubation from 8 biparental species.