Vinegaroons, Mastigoproctus giganteus, are nocturnal desert dwelling ambush predators with catholic diets of virtually any animal they can capture. True to their name, they discharge potent allomones comprised of acetic acid and other short chained organic acids when threatened. Although the environment in which they live is rife with powerful predatory spiders, scorpions, centipedes, carabid beetles, solpugids, and spadefoot toads and rodents, they appear unaffected by predators. The life history strategies of vinegaroons reflect the consequences of their environment and the prey and predators therein.