Corvidae Elaine L, Bierregaard Richard O, Peters Susan E
Department of Biology, University of North Carolina at Charlotte, North Carolina 28223, USA.
J Morphol. 2006 May;267(5):612-22. doi: 10.1002/jmor.10425.
Flight is the overriding characteristic of birds that has influenced most of their morphological, physiological, and behavioral features. Flight adaptations are essential for survival in the wide variety of environments that birds occupy. Therefore, locomotor structure, including skeletal and muscular characteristics, is adapted to reflect the flight style necessitated by different ecological niches. Red-tailed hawks (Buteo jamaicensis) soar to locate their prey, Cooper's hawks (Accipiter cooperii) actively chase down avian prey, and ospreys (Pandion haliaetus) soar and hover to locate fish. In this study, wing ratios, proportions of skeletal elements, and relative sizes of selected flight muscles were compared among these species. Oxidative and glycolytic enzyme activities of several muscles were also analyzed via assays for citrate synthase (CS) and for lactate dehydrogenase (LDH). It was found that structural characteristics of these three raptors differ in ways consistent with prevailing aerodynamic models. The similarity of enzymatic activities among different muscles of the three species shows low physiological differentiation and suggests that wing architecture may play a greater role in determining flight styles for these birds.
飞行是鸟类最显著的特征，它影响了鸟类的大部分形态、生理和行为特征。飞行适应性对于鸟类所占据的各种环境中的生存至关重要。因此，包括骨骼和肌肉特征在内的运动结构会进行适应性调整，以反映不同生态位所必需的飞行方式。红尾鹰（Buteo jamaicensis）翱翔以定位猎物，库珀鹰（Accipiter cooperii）积极追捕鸟类猎物，鹗（Pandion haliaetus）翱翔并悬停以定位鱼类。在这项研究中，对这些物种的翼展比例、骨骼元素比例以及选定飞行肌肉的相对大小进行了比较。还通过柠檬酸合酶（CS）和乳酸脱氢酶（LDH）测定分析了几块肌肉的氧化和糖酵解酶活性。结果发现，这三种猛禽的结构特征在与主流空气动力学模型一致的方面存在差异。这三个物种不同肌肉之间酶活性的相似性表明生理分化程度较低，这表明翅膀结构可能在决定这些鸟类的飞行方式中发挥更大作用。
