Final answer:
The purpose of gluing housefly wings onto tephritid flies was to test the effect of wing markings on preventing predation from jumping spiders, thereby contributing to the understanding of how visual cues affect predator-prey interactions and natural selection.
Step-by-step explanation:
In experiments by Greene and colleagues (1987) with the tephritid fly Zonosemata vittigera and the jumping spider Phidippus apacheanus, the purpose for gluing housefly wings onto the bodies of the tephritid fly was to test for the effect of wing markings in preventing predation. This was done to determine if the wing markings, which resemble the eyes of predators, would deter the jumping spiders from preying on the flies. The research implies that these kinds of conspicuous wing markings could have evolved as an antipredator adaptation through natural selection.
Such experiments contribute to our understanding of predator-prey interactions and the importance of visual cues in the natural world. It shows how predators can influence the evolution of prey species, which supports broader concepts like the one suggested in the hypothesis that one species' response to information can affect natural selection in another species. This is also exemplified in lab tests where birds exhibit fleeing behavior in response to butterflies with eyespots, supporting the idea that such features may confer a selective advantage.