Floral Temperature and Optimal Foraging: Is Heat a Feasible Floral Reward for Pollinators?
Figure 3
An increase in floral temperature means that nectar production can be reduced.
a) Lines show paired values of floral temperature (shown as the difference between floral temperature and take-off temperature, θt−θf) and gain shallowness constant A (where a larger value means that it takes longer for the bee to collect a given amount of nectar), yielding the same optimal net rate of gain (for illustrative purposes, the lines represent the isocline where r* = 0.05 J s−1); b) temperature and gain shallowness pairs yielding the same optimal visit length, td (for illustrative purposes, the lines represent the isocline where td* = 7.5 s). In both figures, the solid black line uses the standard parameter set as described in the methods section, where travel time τ = 10 s. The solid blue line uses the same parameter set, but τ = 20 s. The dotted and dashed lines demonstrate a change in the cost of flight ct (standardised at 0.336 J s−1), representing one way in which non-floral environmental temperature can be included: the dotted lines use ct = 0.9×0.336 J s−1, and the dashed lines use 1.1×0.336 J s−1.