Deserts are dry. Deserts are extreme. True deserts get less than 18 cm of rain per year. True deserts have very few plants. Semi-desert habitats have enough rainfall to support more plant and animal life. Either way, deserts are not easy places for animals to live. Desert animals have evolved to handle the desert's heat and lack of water. They have adapted their bodies and behaviors to the desert climate. Most can survive on small amounts of water and many get all of their water from their food. Some drink maybe once a week and travel considerable distances to find isolated waterholes and springs. Large animals seek shade during the hottest part of the day. Some animals dig a hollow depression into the ground and lie in the cooler soil while others are nocturnal.