Williams C David, Biewener Andrew A
Concord Field Station, Department of Organismic and Evolutionary Biology, Harvard University, Bedford, MA 01730
Concord Field Station, Department of Organismic and Evolutionary Biology, Harvard University, Bedford, MA 01730.
Proc Natl Acad Sci U S A. 2015 Mar 17;112(11):3392-6. doi: 10.1073/pnas.1407298112. Epub 2015 Mar 2.
Individuals traversing challenging obstacles are faced with a decision: they can adopt traversal strategies that minimally disrupt their normal locomotion patterns or they can adopt strategies that substantially alter their gait, conferring new advantages and disadvantages. We flew pigeons (Columba livia) through an array of vertical obstacles in a flight arena, presenting them with this choice. The pigeons selected either a strategy involving only a slight pause in the normal wing beat cycle, or a wings-folded posture granting reduced efficiency but greater stability should a misjudgment lead to collision. The more stable but less efficient flight strategy was not used to traverse easy obstacles with wide gaps for passage but came to dominate the postures used as obstacle challenge increased with narrower gaps and there was a greater chance of a collision. These results indicate that birds weigh potential obstacle negotiation strategies and estimate task difficulty during locomotor pattern selection.
他们可以采用对正常运动模式干扰最小的穿越策略，或者采用会大幅改变其步态的策略，这会带来新的优势和劣势。我们让鸽子（家鸽）在飞行场地中穿越一系列垂直障碍物，给它们这个选择。鸽子要么选择一种只在正常翅膀拍打周期中稍有停顿的策略，要么选择一种翅膀折叠的姿势，这种姿势效率较低，但如果判断失误导致碰撞时稳定性更高。更稳定但效率更低的飞行策略并非用于穿越间隙宽的简易障碍物，而是随着障碍物间隙变窄、碰撞可能性增加，障碍物挑战增大时，逐渐在所用姿势中占据主导。这些结果表明，鸟类在选择运动模式时会权衡潜在的障碍物应对策略并估计任务难度。
