The Seychelles Warbler Acrocephalus sechellensis is a rare island endemic which, from 1920 to 1988, occurred only on Cousin Island (29 ha) in the Seychelles. Despite the saturated nature of this population and the possibility of obtaining higher reproductive success on new nearby islands, inter-island dispersal by Seychelles Warblers is extremely rare (0.10%). We test the hypothesis that Seychelles Warblers show an adaptation typical for island birds: a low-cost reduced-size flight apparatus. We compared the anatomy of the flight apparatus (wing shape, wing loading, skeletal parts and musculature) of Seychelles Warblers with that of three closely related migratory Acrocephalus species (Eurasian Reed Warbler A. scirpaceus, Australian Reed Warbler A. australis and African Reed Warbler A. baeticatus). Seychelles Warblers do not differ from the migratory warblers in pectoral mass and skeletal attachment area relative to body mass, wing shape and wing loading. Seychelles Warblers show the morphological structures required for sustained flight, but may have the behavioural reluctance to cross what they may regard as extensive bodies of water.
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机译：塞舌尔鸣鸟Acrocephalus sechellensis是一种罕见的岛屿特有物种，从1920年到1988年仅发生在塞舌尔的表亲岛（29公顷）上。尽管该人口的饱和状态以及在新的附近岛屿上获得更高繁殖成功的可能性，但塞舌尔莺的岛间扩散极为罕见（0.10％）。我们检验了以下假设：塞舌尔莺（Seychelles Warblers）具有典型的海岛鸟类适应性：一种低成本的小型飞行器。我们将塞舌尔莺的飞行器的解剖结构（机翼形状，机翼载荷，骨骼部位和肌肉组织）与三种紧密相关的迁徙顶头猴物种（欧亚里德莺A. scirpaceus，澳大利亚里德莺A. australis和非洲里德莺）进行了比较。 A. baeticatus）。塞舌尔莺相对于体重，机翼形状和机翼负荷而言，在胸腔质量和骨骼附着区域方面与迁徙鸣莺没有什么不同。塞舌尔莺显示了持续飞行所需的形态结构，但行为上可能不愿穿越他们认为广泛的水体。
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