Fig. 1

Floral nectar production of Rivea ornata and hawk moth visitation rates to flowers at four time periods during anthesis. Study variables related to nectar production (collected from n = 9 flowers), i.e., nectar volume (red), sugar concentration (blue), and sugar amount (green), are plotted against visitation rate (black) (observed from n = 80 flowers). Scale on the left y-axis corresponds to nectar production variables. Scale on the right y-axis is used for visitation rate. Dots and error bars denote means and standard errors