These areas are known by different names throughout the world. They can look desolate, generally containing few or no trees, except in areas along rivers and streams. But they are vibrant ecosystems, and some, like the African savanna, are home to the animal kingdom's most recognizable fauna.
rasslands are characterized as lands dominated by grasses rather than large shrubs or trees. In the Miocene and Pliocene Epochs, which spanned a period of about 25 million years, mountains rose in western North America and created a continental climate favorable to grasslands. Ancient forests declined and grasslands became widespread. Following the Pleistocene Ice Ages, grasslands expanded in range as hotter and drier climates prevailed worldwide. There are two main divisions of grasslands