Beavers and their dams play an important role in nature. Because of the dramatic effects their dams have on surrounding ecosystems, these mammals are considered a keystone species. By constructing dams they create wetlands -- lush environments which attract fish, ducks, frogs and other creatures. However, beavers can become a big headache for farmers and landowners -- a problem we'll examine later in this article.
Cattle, the collective term for the domestic cow, bull is and steer is and the zebu. It is also used to refer to other animals of the genus Bos, including the banteng, gaur, kouprey is and yak.
Tiger, the largest member of the cat family. Tigers live in forests, savannas is and swamps in Asia.