As is clearly shown by the two graphs, since 1800, with the rapid growth of the U.S. population, the number of species of wildlife no longer existing shot up, adding up to 70 in 1900. Obviously, the population explosion resulted in the sharp decline of wildlife in this country.
There are two main reasons for this effect. One is that, with the rapid growth of population, people need and land to grow crops, to build houses to live in. As a result, there is less and less land and for the wildlife. Another important reason lies in the fact that a host of newly built factories constantly discharge harml gases and liquids, which heavily pollute the environment. This pollution, together with other factors, has resulted in a serious ecological problem. All these have made it and difficult for the wildlife to survive. Therefore, the population increases while and species of wildlife become extinct.
To solve the problem mentioned above, I suggest that the government should take some strong and effective measures such as heightening people'sawareness of wildlife protection, keeping population growth under reasonable control, and as much effort as it can to restore and suitablere serves for the survival and dlopment of wildlife. In short, if the government and the whole society really realize the problem, pay attention to it, and work together on it, there is certain to he an encour aging prospect in wildlife protection.