Phoresy
Animals often have to move from place to place to obtain resources. Most animals do so using their own physical effort, but animals of certain species may not be able to transport themselves efficiently in order to access the resources they need. These animals may make use of another animal species to transport them, without causing any injury to the other species. This relationship is known as phoresy. Phoresy, which is a temporary relationship, benefits the passenger species and causes little or no harm to the species doing the transporting.
听力材料：
Now listen to part of a lecture on this topic in a biology class.
So, here's a good example of this. Mites are very small, insect-like creatures. Mites live in tropical climates and feed on nectar and pollen and flowers, but these tropical flowers don't last long. They wilt and fall off quickly and so the mites need to find new flowers in order to get more nectar and pollen to eat, but the mites can't fly and they are so small that it would take them awhile and a lot of effort to climb down one flower, crawl to another one, and climb all the way up again. So, how do they get to the next flower? Well, there's a bird: the hummingbird. Hummingbirds eat the nectar from the same flowers as the mites, so when a hummingbird comes around and sticks its beak into the flowers to get the nectar out, the mites quickly climb onto the hummingbird. Well, as I mentioned, mites are pretty tiny, so the hummingbird isn't harmed in any way and all they do is stick to the hummingbird. Since the hummingbird also goes from flower to flower for nectar, it takes the mites along. Once the hummingbird gets to the next flower, the mites climb off and eat some pollen and nectar there on the new flower. Without the hummingbird carrying them from one flower to another, the mites would find it much more difficult getting food.
Question：
Explain how the example of the mite and hummingbird in the lecture, illustrates the concept of phoresy.
