Final answer:
Bird, bat, and butterfly wings exemplify convergent evolution, where similar structures evolve independently in unrelated species, specifically as homologous structures in birds and bats, and analogous structures in butterflies.
Step-by-step explanation:
The wing structures of birds, bats, and butterflies are classic examples of convergent evolution. This is a process where similar traits evolve independently in species that do not share a common ancestry. The wings of these animals serve the same function - flight - but have evolved from very different original structures. The wings of birds and bats are actually homologous structures because they share a common evolutionary past and both evolved from forelimbs. However, butterfly wings evolved completely independently and are thus analogous structures to bird and bat wings, which means they are similar in function and appearance but do not share ancestral origins.