Figure 1.
Photography's of the prey, the woodland brown butterfly, Lopinga achine.
a. The woodland brown butterfly, L. achine, photographed in natural light. b. The butterfly photographed with a UV filter (Schneider 49 ES Ultraviolet Black 403 which passes UV A radiation (320 to 385 nm)) revealing the strongly UV-reflecting pupils on the hindwing eyespots.
Figure 2.
Light environments in the three treatments.
Irradiance measurements in the experimental room demonstrate the difference in light composition between the three treatments (A High, UV+; B Low, UV+ and C Low, UV -).
Figure 3.
Bird attack on butterfly under high light intensity conditions with UV.
a. Visual inspection of the butterfly by a blue tit–just preceding the bird's attack. b. The bird with the head of the butterfly in its beak after the attack.
Figure 4.
Distribution of attacks in the three treatments.
a. Distribution of blue tit attacks under high light intensity in the presence of UV wavelengths (High, UV+, n = 13). b. Distribution of blue tit attacks under low light intensity in the presence of UV wavelengths (Low, UV+, n = 14). c. Distribution of blue tit attacks under low light intensity in the absence of UV wavelengths (Low, UV-, n = 13).