The Gila, along with the beaded lizard of Mexico, are the only venomous lizards in the world. The Gila monsters distinctive colors warn predators of its venomous bite. Although fairly painful, this bite is not fatal to humans. Gilas are native to southwestern deserts in the US. They eat small mammals such as mice and rats as well as bird eggs and insects. This lizard can store fat in its tail for use when food is scarce.