Mountains are not easy places for plants and animals to thrive. Thin soil, thin air, freezing temperatures, and strong winds make for a harsh environment. The higher up an animal lives, the less there is for it to feed on. Even so, a wide variety of species live in the mountains.
As the altitude increases and the temperature falls, the vegetation and wildlife on the mountain changes. On the lowest slopes, there may be forests and a broad range of animals. At a certain height, the weather becomes too cold and windy for trees to survive; that point is called the timberline, or tree line. The colder the area, the lower the timberline. Above the timberline are meadows and pastures where only low-lying plants, such as grasses and shrubs, alpine flowers, mosses, and lichens can grow. Above the snow line, almost nothing grows, and only the hardiest animals can eke out an existence. In each of these zones, plants and animals are specially adapted for survival.
