Desert
Ayla Boyd
Location
Many deserts are found along 30 degrees latitude north and 30 degrees latitude south (between the red lines on the map).
Some deserts located by mountains and are caused by the "rainshadow" effect. As air moves over a mountain range, and gets cold and loses the ability to hold moisture -- so it rains or snows. When the air moves down the other side of the mountain, it gets warmer. Warm air can hold lots of moisture, so it doesn't rain as much, and a desert is formed.
General Characterists
Weather and Climate
Since deserts usually have only between 10 and 20 percent humidity to trap temperatures and have so few trees and other vegetation to retain heat, they cool down rapidly when the sun sets, and heat up quickly after the sun rises.
Temperature
Precipitation
Landforms
Animals
Animals that live in the hot desert have many adaptations. Some animals never drink, but get their water from seeds (some can contain up to 50% water) and plants. Many of the animals are nocturnal, sleeping during the hot day and only coming out in the cold night to eat and hunt. Some animals rarely spend any time above ground.
Great Mouse-Tailed Bat
Colonies of thousands of mouse-tailed bats occupy roosts in large ruined buildings, often palaces and temples. They feed exclusively on insects, and in those areas where a cool season temporarily depletes the food supply, the bats may enter a deep sleep resembling torpor.
Gila Monster
This formidable, heavy-bodied lizard has a short, usually stout tail, in which it can store fat for use in periods of food shortage. It is gaudily patterned and has brightly colored beadlike scales on its back. The gila lives on the ground and shelters under rocks or in a burrow, which it digs itself or takes over from another animal. It is primarily nocturnal but may emerge during the day in spring.
Fennec Fox
The smallest of the foxes, the fennec fox is identified by its relatively huge ears. It shelters in burrows it digs in the sand and is generally active at night, when it preys on small rodents, birds, insects and lizards. Fennec foxes are sociable animals which mate for life; each pair or family has its own territory. A litter of 2 to 5 young is born in spring after a gestation of 50 to 51 days.
Plants
- Ability to collect and store water
Features that reduce water loss
Saguaro
The stem of the Saguaro Cactus stores all of its water. The stem is green. Photosynthesis occurs in the top layer of the stem instead of in leaves.
Fish Hook Cactus
The fish hook shaped spines of the Fish Hook Cactus help divert heat and shade the growing tip of the plant. Many cacti lean further toward the sun as they grow. Some may eventually uproot themselves.
Dragon Tree
The Dragon Tree is not from the American deserts. It is from the Canary Islands. It has a sap that hardens to a dark red. People call the sap "Dragon's Blood." The sap is sometimes used as a fake stone in jewelry.