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The drongos are a subfamily of small passerine birds of the Old World tropics in the family Dicruridae. This family originally included only the genus ''Dicrurus'' (subfamily Dicrurinae) but Christidis and Boles (2007) expand the family to include the subfamilies Rhipidurinae (Australasian fantails), Monarchinae ( monarchs and paradise flycatchers) and Grallininae (magpie-larks).〔Christidis, Les; Walter Boles (2008) Systematics and Taxonomy of Australian Birds. Csiro Publishing, Australia. p. 174〕 The name is originally from the indigenous language of Madagascar, where it refers to local species, but is now used to refer to all members of the subfamily. The family is usually treated as having two genera, ''Chaetorhynchus'' and ''Dicrurus''. The genus ''Chaetorhynchus'' contains a single species, the New Guinea endemic pygmy drongo. The placement of this species in the family is highly dubious due to both morphological and genetic differences, and it has recently been placed, along with the closely related Silktail of Fiji, with the fantails (Rhipiduridae). The remaining genus contains the remaining 25 species of drongo. The family Dicruridae is believed to be most likely of Indo Malayan origin, with a colonization of Africa about 15 million years ago. Dispersal across the Wallace Line into Australasia is estimated to have been more recent, around 6 mya.〔Eric Pasquet, Jean-Marc Pons, Jerome Fuchs, Corinne Cruaud, Vincent Bretagnolle (2007) Evolutionary history and biogeography of the drongos (Dicruridae), a tropical Old World clade of corvoid passerines. Molecular Phylogenetics and Evolution 45:158–167〕 These insectivorous birds are usually found in open forests or bush. Most are black or dark grey in colour, sometimes with metallic tints. They have long forked tails; some Asian species have elaborate tail decorations. They have short legs and sit very upright whilst perched, like a shrike. They flycatch or take prey from the ground. Some drongos, especially the greater racket-tailed drongo, are noted for their ability to mimic other birds and even mammals. Two to four eggs are laid in a nest high in a tree. Despite their small size, they are aggressive and fearless, and will attack much larger species if their nest or young are threatened. Several species of animals and birds respond to drongos' alarm calls, which often warn of the presence of a predator. Fork-tailed or common drongos in the Kalahari desert are known to use alarm calls in the absence of a predator to cause animals to flee and abandon food, which they eat, getting up to 23% of their food this way. They not only use their own alarm calls, but imitate those of many species, either their victim's or that of another species that the victim responds to. If the call of one species is not effective, perhaps because of habituation, the drongo will try another; 51 different calls are known to be imitated. In one test on pied babblers, the babbler ignored an alarm call repeated three times when there was no danger, but continued to respond to different calls. Researchers have considered the possibility that these drongos possess theory of mind, not fully shown in any animal other than humans, but doubt this capability.〔(National Geographic: African Bird Shouts False Alarms to Deceive and Steal, Study Shows Drongos in the Kalahari are masters of deception, 1 May 2014 )〕〔Tom Flower, Fork-tailed drongos use deceptive mimicked alarm calls to steal food, Proc. R. Soc. B rspb20101932; published ahead of print November 3, 2010, doi:10.1098/rspb.2010.1932 1471-2954, http://rspb.royalsocietypublishing.org/content/early/2010/10/27/rspb.2010.1932.full〕 ==Insult== The word ''drongo'' is used in Australian English as a mild form of insult meaning "idiot" or "stupid fellow". This usage derives from an Australian racehorse of the same name (apparently after the spangled drongo, Dicrurus bracteatus) in the 1920s that never won despite many starts.〔〔"''Drongo''", entry in 1970, Bill Wannan, ''Australian Folklore'', Lansdowne Press, reprint 1979, ISBN 0-7018-1309-1, page 200.〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「drongo」の詳細全文を読む スポンサード リンク
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