A Test for Character Displacement Among Three Species of Fairy-wrens (Maluridae, Malurus)

Abstract

Lengths of tarsus and wing, and bill dimensions, of museum specimens of Superb Malunus cyaneus, Variegated M. lamberti and White-winged Fairy-wrens M. leucopterus from all parts of their ranges (except Tasmania) were measured. Wing length of Superb Fairy-wrens increased progressively southwards: no other character measurements differed between sexes or latitudinal zones. In most zones Variegated Fairy-wren males were larger than females. White-winged Fairy-wren measurements of tarsus and bill did not vary between sexes or zones but winglength increased from north to south. No differences consistent with character displacement could be established between zones of allopatry and sympatry for any of the species. Variation in traits appears to be clinal or to have developed in isolation.