Courtship behaviour in the common eastern firefly, Photinus pyralis, involves male fireflies producing specific bioluminescent flash patterns (pulses of light) to:
Scientists investigated firefly courtship behaviour by feeding a population of sexually active male fireflies a diet containing the neonicotinoid insecticide clothianidin (CLO). The scientists also fed a separate control population of sexually active male fireflies a diet without CLO.
They determined the percentage of males making patrolling flashes or warning flashes in each population.
Table 1 shows their results.
Table 1
| Population | Percentage of males making patrolling flashes (%) | Percentage of males making warning flashes (%) |
|---|---|---|
| Males fed CLO | 74.8 | 22.4 |
| Males not fed CLO (control) | 89.4 | 4.6 |
There were 750750750 males in the control population. Each male made only one type of flash pattern.
Use this information and Table 1 to calculate the number of males making dialogue flashes in the control population.
Suggest one change the scientists could make to both firefly populations to increase the number of male dialogue flashes.
The scientists also investigated the effect on female firefly courtship behaviour of exposing male fireflies to CLO. Table 2 shows their results.
Table 2
| Population | Median duration of dialogue flash exchange with females (s) |
|---|---|
| Males fed CLO | 15 |
| Males not fed CLO (control) | 45 |
Clothianidin (CLO) is a widely used agricultural pesticide that can leach into surrounding habitats via agricultural runoff, contaminating wild firefly habitats.
Suggest and explain the effect that CLO pollution in wild firefly habitats will have on firefly reproduction and species recognition. Use information from Table 1 and Table 2 in your answer.
