Final answer:
The phenomenon where similar features evolve independently in different species is known as convergent evolution. Such features, like the wings of hummingbirds and house flies, are called analogous structures because they perform the same function without deriving from a common ancestor.
Step-by-step explanation:
The term that best describes the phenomenon where similar characteristics evolve independently in different species that do not share a common ancestry is convergent evolution. This can be seen in the way both hummingbirds and house flies have developed wings for flight despite the fact that these structures evolved from very different original parts. The wings serve similar functions in both organisms, allowing them to fly, but they are considered analogous structures because they do not share a common evolutionary origin.
Another example of convergent evolution is the development of streamlined body shapes in both fishes and whales, which have adapted to moving through water, despite the fact that whales are mammals and not closely related to fishes. These adaptations are a response to environmental pressures and are indicative of convergent evolution in action.