Fig. 3.

Relationship between parental cooperation and the adult sex ratio. a Faint white lines illustrate each iteration of the bootstrap, which randomly sampled an adult sex ratio and parental care estimate from each population’s uncertainty distribution and fitted them to the a priori quadratic model (shown in inset, Eq. 10). b Proportion of monitored plover families that exhibit parental cooperation (white) or single-parent care by males (green) or females (orange). Sample sizes reflect number of families monitored per population. Original plover illustrations and silhouettes by L.J.E.-P