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Currawongs are three species of medium-sized passerine birds belonging to the genus ''Strepera'' in the family Artamidae native to Australasia. These are the grey currawong (''Strepera versicolor''), pied currawong (''S. graculina''), and black currawong (''S. fuliginosa''). The common name comes from the call of the familiar pied currawong of eastern Australia and is onomatopoeic. They were formerly known as crow-shrikes or bell-magpies. Despite their resemblance to crows and ravens, they are only distantly related to the corvidae, instead belonging to an Afro-Asian radiation of birds of superfamily Malaconotoidea. The true currawongs are a little larger than the Australian magpie, smaller than the ravens (except possibly the little raven, which is only slightly larger on average), but broadly similar in appearance. They are easily distinguished by their yellow eyes, in contrast to the red eyes of a magpie and white eyes of Australian crows and ravens. Currawongs are also characterised by the hooked tips of their long, sharply pointed beaks.〔''Amazing Facts about Australian Birds'', by Karin Cox and Steve Parish, Steve Parish Publishing, 2008.〕 They are not as terrestrial as the magpie and have shorter legs. They are omnivorous, foraging in foliage, on tree trunks and limbs, and on the ground, taking insects and larvae (often dug out from under the bark of trees), fruit, and the nestlings of other birds. They are distinguishable from magpies and crows by their comical flight style in amongst foliage, appearing to almost fall about from branch to branch as if they were inept flyers. ==Taxonomy and evolution== Ornithologist Richard Bowdler Sharpe held that currawongs were more closely related to crows and ravens than the Australian magpie and butcherbirds, and duly placed them in the Corvidae. A review of the family Cracticidae by ornithologist John Albert Leach in 1914, during which he had studied their musculature, found that all three genera were closely related. Ornithologists Charles Sibley and Jon Ahlquist recognised the close relationship between the woodswallows and the butcherbirds and relatives in 1985, and combined them into a Cracticini clade, which later became the family Artamidae in the official Australian checklist in 2008. The International Ornithologists’ Union has maintained the two clades as separate families, hence currawongs are listed along with butcherbirds, magpie and ''Peltops''. The family Cracticidae has its greatest diversity in Australia, which suggests that the radiation of its insectivorous and scavenger members to occupy various niches took place there. The butcherbirds became predators of small animals, much like the northern hemisphere shrikes, while the Australian magpie became a predominantly ground-hunting omnivore, with the currawongs generally hunting in both living and fallen trees, scavenging and hunting insects and small vertebrates, and occupying in Australia the niche of many Eurasian corvids. Currawongs and indeed all members of the broader Artamidae are part of a larger group of African shrike-like birds including bushshrikes (Malaconotidae), helmetshrikes (Prionopidae), ioras (Aegithinidae), and vangas (Vangidae), which were defined as the superfamily Malaconotoidea by Cacraft and colleagues in 2004. They are thus only distantly related to crows and ravens, which are in a separate superfamily Corvoidea. 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「currawong」の詳細全文を読む スポンサード リンク
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