For cockatiels, the minimum power output was 1.3W at a speed of 5 ms-1. The maximum power output was 3.7W at a speed of 14 ms-1. For doves, the minimum power output was 4.3W at a speed of 7 ms-1. The maximum power output was 7.5W at a speed of 17 ms-1. The mass-specific power output of the dove was higher than the cockatiel at all speeds except 14 ms-1. Wing-beat in cockatiels was minimum at 9 ms-1. It was 7 to 13 ms-1 in doves. These results did not support the idea that minimum wing-beat frequency corresponded to the birds’ minimum power speed. Instead, they showed a close relationship between work and power. When compared to the mechanical power curve of the magpie, cockatiels and doves had a much higher mass-specific pectoralis power output. Although the magpie has the morphology and pectoralis muscles to support faster flight, the shape of their wings limited maximum forward velocity. Having broad, rounded wings and a long tail resulted in a lower drag/thrust ration and increased drag. On the other hand, the cockatiel and dove have pointed wings and experienced less drag and a higher drag/thrust ratio which allowed them to fly at higher velocities. Additionally, magpies have a unique flight style in which wing-beat gait, flight velocity and altitude was constantly changed. This style could have potentially been limiting on power output. Overall, the results of cockatiels and doves mechanical power curves did not support the aerodynamic theory at low and high velocities. The pectoral power used at slow speeds was predicted to be too high, and the pectoral power used at fast speeds was predicted to be too low.
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