Desert organisms must be able to adapt to extreme daily fluctuations in temperature, from cold in the evenings to scorchingly hot during the daytime hours. They must be able to survive in a harsh environment where water is a limiting factor. Cacti and succulents found in this biome can store moisture in the sap in their stems. They usually have a waxy cuticle to keep water within the plant. The leaves of cacti are reduced to spines, limiting their surface area and amount of stomates. This in turn, helps retain water inside the plant. Roots are shallow and spread out near the surface. In the event it does rain briefly, those roots will quickly absorb water before it evaporates. Animals in the desert can use behaviors as adaptations. Many are nocturnal and seek shelter in burrows out of the direct sunlight during the daytime hours. Kangaroo rats can survive where there is almost no water and yet, their bodies contain the same amount of water as other organisms. They can convert dry seeds into water, have specialized kidneys which waste very little water and only come out in the evenings when it is cool outside. Besides mammals like the kangaroo rat, other animals found in the desert include: arachnids, birds, insects, reptiles and amphibians. Each is uniquely adapted to life in this harsh environment.
A desert is a place with very little precipitation. Although many deserts are warm, deserts can also be cold. The term "desert" simply means that there is very little rain or snowfall.
Let's use the typical warm desert as an example of a habitat. This type of desert is a difficult place for plants and animals to live. It is full of extremes. In the day time, the desert is very hot. The sun bakes the soil or sand. At night, the absence of cloud leads to extreme cooling as the heat goes up into the air. The ground becomes cold.
Plants adapt to these extremes by growing with waxy coatings that allow them to conserve moisture. They also have very small leaves, so that they do not have a lot of surface area through which they can lose moisture. Plants such as cacti are designed to store moisture when it falls. Plants also time their reproduction to take advantage of the rain. When the rain falls, they bloom.
Desert animals also have amazing adaptations to this environment. In the heat of the day, many desert animals stay cool by taking shelter underground or under rocks. Nocturnal animals are common in deserts. Desert animals also move in ways that reduce the amount of contact that they make with hot sand. For example, snakes use a sidewinding motion so that they do not sit flat on the ground. Desert animals also have internal adaptations to extreme temperatures. For example, the camel's red blood cells are an oval shape, which allows the blood to move easily even when the camel is severely dehydrated.