Take human diseases as an example. From the origin of mankind to the present, no more than three diseases have been truly eliminated by mankind. There are countless species that can threaten human life, such as some highly contagious viruses, bacteria and cancer, which may end human life in a certain period of time. The reason why human beings can become the masters of the earth has nothing to do with whether human beings exist at the top of the food chain, but it has a lot to do with human inventions. People think that human beings dominate the earth, but this is only the appearance.
Next, let's talk about the food chain. There are many kinds of food chains, for example, insects are eaten by birds, birds are eaten by eagles, eagles are eaten by cats, cats are hunted by wolves, wolves are afraid of tigers, and tigers are afraid of diseases. In the end, the disease killed the tiger, and the tiger bred insects for birds. Another example is "Whale Falling". Whales are the largest creatures in the ocean. It often feeds on all kinds of fish. After its death, it will breed all kinds of marine life, and marine life will raise fish and so on. Another example is plants. Therefore, plants fall to the ground to form new plants, absorb carbon dioxide and spit out oxygen, while humans absorb oxygen and spit out carbon dioxide. When plants or humans are corroded, they will add nutrients to the soil again. These effects will breed new plants and creatures and so on.
Therefore, there is not only one food chain in nature, but also many intersections. Humans become masters because of their rapid evolution and high level of intellectual civilization. In fact, human beings have gone beyond the food chain.