[00:00.30]
[00:01.51]As is shown by the two graphs,
[00:04.00]the U.S. population soared from 2 million to 250 million from 1800 to 1990.
[00:12.10]In contrast, the number of wildlife species no longer existing shot up,
[00:17.93]adding up to 70 over the same period of time.
[00:21.89]It is obvious that the extinction of wildlife resulted from the population explosion.
[00:27.74]We may cite a variety of reasons for this situation.
[00:31.90]First of all, the destruction of ecological balance plays a pushing role.
[00:36.90]Due to population problems,
[00:39.18]pollution and desertification are becoming increasingly serious.
[00:43.84]Furthermore, a great number of species were killed for food, for money and even for fun.
[00:51.03]Even worse, with the rapid growth of human population,
[00:54.71]inhabitable areas were expanding so fast that few areas were left for wild animals.
[01:01.24]To sum up, it is imperative for us to take effective measures to protect wildlife.
[01:06.89]Firstly, the U.S. government should pour more investment into wildlife protection
[01:12.23]in a bid to create a better environment.
[01:15.05]Secondly, the birth rate in the U.S. must be put under control
[01:20.16]as the dramatically expanding population gives rise to serious environmental problems.
[01:26.77]