| 词汇 | alula |
| 释义 | BETA Examples of alulaalula isn’t in the Cambridge Dictionary yet. You can help! In birds, the slots formed by the alula and primary flight feathers allow these animals to have high wing loadings and fairly low stalling speeds. From Wikipedia This example is from Wikipedia and may be reused under a CC BY-SA license. The evolution of the modern avian traits such as the compact body, clawless wing and the alula are now known to appear over successive stages. From Wikipedia This example is from Wikipedia and may be reused under a CC BY-SA license. The alula, by contrast, is formed by the thumb, which does not completely fuse with the other hand-bones. From Wikipedia This example is from Wikipedia and may be reused under a CC BY-SA license. Primary coverts and alula are grey with white margins. From Wikipedia This example is from Wikipedia and may be reused under a CC BY-SA license. Since these species are not closely related to modern birds, either the alula evolved twice, or it did so more than 130 million years ago. From Wikipedia This example is from Wikipedia and may be reused under a CC BY-SA license. The reduced fingers suggest that it might have had an alula. From Wikipedia This example is from Wikipedia and may be reused under a CC BY-SA license. However, alula feathers are definitely an aid to slow flight. From Wikipedia This example is from Wikipedia and may be reused under a CC BY-SA license. The alula is the freely moving first digit, a bird's thumb, and typically bears three to five small flight feathers, with the exact number depending on the species. From Wikipedia This example is from Wikipedia and may be reused under a CC BY-SA license. In the flexed wing the outer squama of the alula is turned upside down above the inner squama, the latter not being affected by the movement of the wing. From Wikipedia This example is from Wikipedia and may be reused under a CC BY-SA license. The presence of alula and a complete set of aerodynamic asymmetric feathers arranged forming a modern wing, indicate well develop flight capabilities, as in many other enantiornithine taxa. From Wikipedia This example is from Wikipedia and may be reused under a CC BY-SA license. In the flexed wing, the outer squama of the alula is turned upside down above the inner squama, the latter not being affected by the movement of the wing. From Wikipedia This example is from Wikipedia and may be reused under a CC BY-SA license. The mantle proper is a medium to dark gray-blue as are the tertials and upperwing-coverts, turning to a dark gray at the median, greater and primary coverts and the alula. From Wikipedia This example is from Wikipedia and may be reused under a CC BY-SA license. When flying at slow speeds or landing, the bird moves its alula slightly upwards and forward, which creates a small slot on the wing's leading edge. From Wikipedia This example is from Wikipedia and may be reused under a CC BY-SA license. |
反思网英语在线翻译词典收录了377474条英语词汇在线翻译词条，基本涵盖了全部常用英语词汇的中英文双语翻译及用法，是英语学习的有利工具。