The major desert biomes of the Earth are geographically found at between 25 to 25 degrees North and South latitude, in the interiors of continents. Climatically, deserts are influenced by descending air currents which limit the formation of precipitation. Many desert areas have less than 25 millimeters of precipitation annually. Cactus are a common type of drought resistant plant found in deserts. Most desert mammals tend to be nocturnal to avoid the high temperatures.
Lizards are quite common in desert habitats.
Because productivity is low, the litter layer is comparably limited and organic content of surface soil layers is very low. Also, evaporation tends to concentrate salts at the soil surface. Mediterranean Shrubland Mediterranean shrubland has a very specific spatial distribution. It is found in a narrow zone between 32 and 40 degrees latitude North and South on the west coasts of the continents. This area has a dry climate because of the dominance of the subtropical high pressure zone during the fall, summer, and spring months.