Some grasshoppers are ground dwellers that have lived on the desert pavement so long that they even look like stones. Many come in conventional grasshopper shape but are mottled in shades of gray and mauve. The toadhopper that inhabits wash bottoms and rocky areas has taken on the color, shape, and texture of rock. Fat and squatty, he will camouflage himself, tucking his antenna right down in front of his face and pulling his legs in close to his body. You can’t even see him when you know he is there. By comparison, the lubber grasshopper advertises his presence. He is a large black beast gaudily marked in coral-snake red and yellow. Apparently these colors warn predators that the lubber is distasteful. He is out and about from late morning on. [Illustration: Whiptail scorpions, which are not true scorpions, have no stinger. They pursue insects and other invertebrates and kill them with powerful pincers.] [Illustration: Eleven species of stinging scorpions live in the park. Coloration varies from dull-cream through brown to shiny black.] Also seen in broad daylight is the worm-like millipede rippling its way across the desert pavement. This maroon-colored plant eater has up to 200 legs arranged in short double pairs along a 13-centimeter (5-inch), many-segmented body. He isn’t poisonous and won’t sting or bite, but he may emit a substance lethal enough to kill other insects in a confined area. Of course, the chief daily events of life in the desert are eating and being eaten, and predators that favor a certain diet make it their business to be out when their kind of dinner is around. Thus the grasshopper-eating lizards brave the daytime heat to do their hunting. Most often seen is the quick moving western whiptail. The greenish collared lizard may be seen racing along on his hind legs like a miniature dinosaur. Lizards are about the biggest ground dwellers you scare up on a noonday walk—unless you happen on a lizard-eater like the big, pink western coachwhip snake. At twilight you become most aware of the desert’s residents. The coolness brings them out. Some must hurry and eat before it gets full dark, while others have the whole night ahead of them. At first you may sense the desert’s coming-to-life more by listening than by looking. You hear the lesser nighthawk trilling like a toad. Then, without warning, the whole desert begins to sing, as katydids, grasshoppers, and crickets join in a tapestry of sound so rich you can almost touch it.