In contrast to the lush, wet Amazon basin, the Atacama Desert is barren and arid. It is the driest desert on Earth. However, the tough and hardy guanacos can survive here. A guanaco takes a dust bath. Fogs rolling in off the Pacific Ocean are the key to survival in the Atacama. Dew condenses on the cactuses and lichen. Diuca finches drink the dew and guanacos eat the lichen, thus obtaining the water they need to survive. The guanacos also eat a parasitic plant that grows on the cacti.