Behavioral Lateralization and Optimal Route Choice in Flying Budgerigars
Figure 5
A. Illustration of total transit times as predicted by a model of a flock of budgerigars negotiating two simultaneously presented apertures of width d mm (left-hand aperture) and (D-d) mm (right-hand aperture), where D, the sum of the widths of the two apertures, is 100 mm.
The curves show the variation of the total transit time with d for strategies A (blue), B (green), C (black), D (dashed black) and E (red), as described in the text. For clarity, the curve for strategy D is shown displaced slightly upwards. B. Probability functions for the choice of the left-hand aperture (blue curve) and the right-hand aperture (red curve) as a function of the width d of the left-hand aperture, for the optimum strategy (E) described in the text. C. Model showing choice probability for the left-hand aperture as a function of its width, for individual birds with a range of different bias parameters (B) varying from 0 mm to 100 mm in steps of 10 mm. The choice probability for each bird is modeled by a step function (dashed blue curve). The continuous red curve shows the resulting average choice probability function for the entire flock. D. Choice probability functions for the left-hand aperture for individual birds with a range of different bias parameters (B) varying from 0 mm to 100 mm in steps of 10 mm. The choice probability for each bird is modeled by a logistic function (dashed blue curve). The continuous red curve shows the resulting average choice probability function for the entire flock.