Deserts and How Life Survives

A land with almost no rain

Imagine a place where it almost never rains. The ground is dry and cracked, the sun blazes down, and water is very hard to find. This is a desert. Deserts can be tricky places to live, yet many amazing plants and animals call them home. How do they do it? Let's find out.

What makes a desert a desert?

When you hear the word "desert," you probably picture rolling sand dunes under a hot sun. Many deserts do look like that, such as the huge Sahara Desert in Africa. But the real thing that makes a place a desert is not sand, and it is not even heat. It is being dry.

A desert is any place that gets very little rain, usually less than other places get in a whole year. Some deserts are scorching hot in the day, but they can turn surprisingly cold at night, because there are no clouds to hold the warmth in. And a few deserts are actually freezing all the time. The biggest desert in the world is not the sandy Sahara, but the icy land of Antarctica, which counts as a desert because so little rain or snow falls there.

Living without water

Every living thing needs water to survive. So how can anything live in a place with hardly any? The answer is that desert plants and animals have special features that help them survive. These special features are called adaptations. An adaptation is something about a living thing's body or its behaviour that is perfectly suited to its home.

Desert living things have two big problems to solve: how to get enough water, and how to stop water escaping from their bodies in the heat. Let's see some clever solutions.

Clever desert plants

Look at a cactus. A cactus is a master at surviving the desert. When rain does fall, a cactus drinks up as much as it can and stores the water inside its thick, juicy stem, a bit like a living water bottle. That stored water keeps the cactus alive through the long dry months.

Have you noticed that a cactus has sharp spines instead of soft, flat leaves? This is another clever adaptation. Wide leaves would lose a lot of water in the heat. Thin spines lose far less, and they have a bonus job too: they stop thirsty animals from biting into the cactus to steal its water. Many desert plants also grow very long roots that spread out wide and shallow, ready to soak up every drop the moment it rains.

Amazing desert animals

Desert animals are just as clever. The most famous is the camel, sometimes called the ship of the desert.

People used to think a camel's hump was full of water, but it is actually full of fat. When food is hard to find, the camel's body uses up this fat for energy. Camels can also drink a huge amount of water in one go and then go for many days without drinking again, because their bodies are so good at not wasting water. They barely sweat, and they have long eyelashes and closeable nostrils to keep out the blowing sand.

Smaller animals have a different trick: they simply hide from the heat. The fennec fox has enormous ears. These big ears help it hear prey, but they also let heat escape from its body to keep it cool, like opening a window on a hot day. Many desert creatures, such as snakes, lizards, scorpions and small rodents, dig burrows underground. Below the surface it is cooler and damper, so they rest there during the burning day and come out to hunt for food at night, when the air is cool. This is the same way that nighttime animals all over the world stay safe and comfortable.

Why life finds a way

Deserts show us something wonderful about nature: living things can survive almost anywhere if they have the right adaptations. Over a very long time, the plants and animals that were best at saving water and beating the heat survived and had young. Bit by bit, this is how desert life became so perfectly suited to one of the toughest places on Earth.

Make a mini desert experiment

You can see how water hides from heat with a simple experiment at home, with a grown-up to help. Pour the same small amount of water into two saucers. Leave one saucer in a warm, sunny spot, like a windowsill, and put the other in a cool, shady place, like a cupboard.

Check them after a few hours and again the next day. Which saucer's water disappeared first? The water in the warm, sunny spot dries up faster. This shows you why desert plants and animals work so hard to keep their water hidden away from the sun, just as you might keep an ice cream out of the heat so it does not melt.

You could also make a desert nature table at home. Draw or model a cactus, a camel and a fennec fox, and label each adaptation that helps it survive.

Deserts are one of Earth's many habitats. Compare them with a very different watery world in Oceans and Sea Life. And to learn how living things connect and feed each other in any habitat, read Animals and Their Homes.