Grassland biodiversity.

Grasslands comprise one of Earth's dominant biomes, accounting for up to 40% of its terrestrial area (Figure 1). The fundamental components of grassland habitats are grasses and grass-like plants, but diverse assemblages of other plant life forms and diverse animal communities also contribute to grassland biodiversity. Grasses have evolved traits allowing them to cope with climatic extremes, specific soil conditions, fires, and herbivory, all of which sustain grasslands by limiting the establishment, survival, growth, and dominance of woody vegetation. Grasslands occur in almost all climatic zones, except the poles, extreme arid zones, and the highest mountains (Figure 1). Temperate grassland habitats include Eurasian steppes, North American prairies, the pampas lowlands of South America, and Patagonian steppe. Tropical and subtropical grasslands (savannas) occur mostly in Africa and Australia, but are also found in the north of South America, in the southern United States, South Asia, and Southeast Asia.