Malurids are small to medium birds, inhabiting a wide range of environments from rainforest to desert, although most species inhabit grassland or scrub. The grasswrens are well camouflaged with black and brown patterns, but other species often have brilliantly coloured plumage, especially in the males. They are insectivorous, typically foraging in underbrush. They build domed nests in areas of dense vegetation, and it is not unusual for the young to remain in the nest and assist in raising chicks from later clutches. Fairywrens are notable for several peculiar behavioral characteristics. They are socially monogamous and sexually promiscuous, meaning that although they form pairs between one male and one female, each partner will mate with other individuals and even assist in raising the young from such pairings. Males of several species pluck petals of conspicuous colours and display them to females for reasons unknown. The song of fairywrens is pleasant and complex, and at least two species (superb and splendid) possess, in addition to the alarm calls common to – and universally understood by – most small birds, another vocalization used when confronted by predators. This, termed "Type II Vocalization," is song-like and used when confronted by calling butcherbirds, and sometimes other predatory birds. Its purpose is, however, unknown it does not seem to be a warning call.