Deserts cover nearly one-fifth of the Earth's land surface. Even in these sand-filled expanses that dot the globe, much life can be found, from plants like cacti and sagebrush to well-adapted animals such as the Gila monster and the sidewinder. Discover how the process of desertification continually changes more land into deserts each and every year. A hands-on demonstration helps explain the different adaptations used by plants and animals to conserve water, while a visit with a herpetologist showcases the unusual adaptations of the deadly sidewinder.