Grassland Biome

Grasslands
Grasslands (also called greenswards) are areas where the vegetation is dominated by grasses and other herbaceous (non-woody) plants. Grasslands occur naturally on all continents except Antarctica.
Grassland vegetation can vary in height from very short, as in Chalk Downland where the vegetation may be less than (12 in) high, to quite tall, as in the case of North American tall grass prairie, South American grasslands and African savanna. Woody plants, shrubs or trees, may occur on some grasslands - forming savannas, scrubby grassland or semi-wooded grassland, such as the African savannas or the Iberian Dehesa. Such grasslands are sometimes referred to as wood-pasture or woodland.
Grasslands cover nearly fifty percent of the land surface of the continent of Africa. While grasslands in general support diverse wildlife, given the lack of hiding places for predators, the African Savanna regions support a much greater diversity in wildlife than do temperate grasslands.
The appearance of mountains in the western United States during the Miocene and Pliocene epochs, a period of some 25 million years, created a continental climate favorable to the evolution of grasslands. Existing forest biomes declined, and grasslands became much more widespread. Following the Pleistocene Ice Ages, grasslands expanded in range in the hotter, drier climates, and began to become the dominant land feature worldwide.
Grasslands are of vital importance for raising livestock for human consumption and for milk and other dairy products.
Grassland vegetation remains dominant in a particular area usually due to grazing, cutting, or natural or manmade fires, all discouraging colonization by and survival of tree and shrub seedlings. Some of the world's largest expanses of grassland are found in African savanna, and these are maintained by wild herbivores as well as by nomadic pastoralists and their cattle, sheep or goats.
Grasslands may occur naturally or as the result of human activity. Grasslands created and maintained by human activity are called anthropogenic grasslands. Hunting peoples around the world often set regular fires to maintain and extend grasslands, and prevent fire-intolerant trees and shrubs from taking hold. The tall grass prairies in the American Midwest may have been extended eastward into Illinois, Indiana, and Ohio by human agency. Much grassland in northwest Europe developed after the Neolithic Period, when people gradually cleared the forest to create areas for raising their livestock.
Tropical and subtropical grasslands
These grasslands are classified with tropical and subtropical savannas and shrublands as the tropical and subtropical grasslands, savannas, and shrublands biome. Notable tropical and subtropical grasslands include the Llanos grasslands of northern South America.
Temperate grasslands
Mid-latitude grasslands, including the Prairie and Pacific Grasslands of North America, the Pampas of Argentina, Brazil and Uruguay, calcareous downland, and the steppes of Europe. They are classified with temperate savannas and shrublands as the temperate grasslands, savannas, and shrublands biome. Temperate grasslands are the home to many large herbivores, such as bison, gazelles, zebras, rhinoceroses, and wild horses. Carnivores like lions, wolves and cheetahs and leopards are also found in temperate grasslands. Other animals of this region include: deer, prairie dogs, mice, jack rabbits, skunks, coyotes, snakes, fox, owls, badgers, blackbirds (both Old and New World varieties), grasshoppers, meadowlarks, sparrows, quails, hawks and hyenas.
Flooded grasslands
Grasslands that are flooded seasonally or year-round, like the Everglades of Florida or the Pantanal of Brazil, Bolivia and Paraguay. They are classified with flooded savannas as the flooded grasslands and savannas biome and occur mostly in the tropics and subtropics.
(Mountain) grasslands
High-altitude grasslands located on high mountain ranges around the world, like the Páramo of the Andes Mountains are part of the mountain grasslands and shrublands biome and also constitute tundra.
Tundra grasslands
Similar to mountain grasslands, polar arctic tundra can have grasses, but high soil moisture means that few tundras are grass-dominated today. However, during the Pleistocene ice ages, a polar grassland known as steppe-tundra occupied large areas of the Northern hemisphere. These are in the tundra biome.
Desert and xeric grasslands
Also called desert grasslands, this is composed of sparse grassland eco-regions located in the deserts and xeric shrublands biome.