The SONORAN DESERT is a North American desert that covers large parts of the SOUTHWEST in the United States and Northwestern parts of Mexico. The Sonoran Desert is especially dry and warm compared to other North American deserts and while it might seem surprising that many plants and animals live in this desert, some really thrive. The SAGUARO, a type of cactus that only grows in the Sonoran Desert, can actually live to be over 150 years old.